{"id":19260,"date":"2026-06-10T05:12:47","date_gmt":"2026-06-10T05:12:47","guid":{"rendered":"https:\/\/tradefoxapp.com\/?p=19260"},"modified":"2026-06-10T05:16:34","modified_gmt":"2026-06-10T05:16:34","slug":"air-bricks","status":"publish","type":"post","link":"https:\/\/tradefoxapp.com\/fr\/air-bricks\/","title":{"rendered":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp"},"content":{"rendered":"<div data-elementor-type=\"wp-post\" data-elementor-id=\"19260\" class=\"elementor elementor-19260\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-bd69d62 e-flex e-con-boxed e-con e-parent\" data-id=\"bd69d62\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-cfb4151 elementor-widget elementor-widget-text-editor\" data-id=\"cfb4151\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Underfloor ventilation rarely gets the attention it deserves on site, yet it accounts for a large share of the damp and timber decay surveyors find across UK housing stock. Get it right and the subfloor void stays dry for the life of the building. Get it wrong and you are looking at rot, mould, and remedial work that costs far more than the vents ever would.<\/span><\/p><p><span style=\"font-weight: 400;\">This guide breaks down how air bricks work, where they belong, what UK regulations actually require, and why a blocked vent does so much damage. It is written for trade, not for DIY.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-1648910 e-flex e-con-boxed e-con e-parent\" data-id=\"1648910\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-f6d514b elementor-widget elementor-widget-heading\" data-id=\"f6d514b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">What an Air Brick Actually Does\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fdbd47d elementor-widget elementor-widget-text-editor\" data-id=\"fdbd47d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">An air brick is a perforated unit, usually clay or moulded plastic, sized to fit standard brick coursing and built into the external wall at low level. The job is simple to describe and easy to underestimate: move air through the space beneath a suspended floor so that ground moisture cannot sit and condense on the timbers.<\/span><\/p><p><span style=\"font-weight: 400;\">Suspended timber floors and beam-and-block floors both rely on a ventilated void underneath. Ground moisture is constant. Without a steady exchange of air, humidity in that void climbs, and once timber moisture content creeps past roughly 20 percent you have created the conditions wet rot and dry rot need to take hold.<\/span><\/p><p><span style=\"font-weight: 400;\">There is a second function worth knowing. Ventilated voids also help disperse ground gases such as radon, which matters in affected regions.<\/span><\/p><p><span style=\"font-weight: 400;\">One structural point to keep in mind: vents and air bricks provide no structural support. Any opening formed in load-bearing brickwork needs the load carried by a lintel or by the unit&#8217;s own design allowance.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-75eab39 e-flex e-con-boxed e-con e-parent\" data-id=\"75eab39\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-609e6e4 elementor-widget elementor-widget-heading\" data-id=\"609e6e4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Cross-Flow: The Principle That Makes It Work\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-908a734 elementor-widget elementor-widget-text-editor\" data-id=\"908a734\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">A single row of vents on one elevation does almost nothing. The principle behind effective underfloor ventilation is cross-flow. Air has to enter one side of the building and leave the opposite side, sweeping the whole void as it goes.<\/span><\/p><p><span style=\"font-weight: 400;\">Approved Document C 4.14(b) is explicit that openings should sit on two opposing external walls so the ventilating air has a free path between opposite sides and to all parts of the void.<\/span><\/p><p><span style=\"font-weight: 400;\">Two failure points come up again and again:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d488066 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"d488066\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>One-sided ventilation. <\/b>Vents on a single wall leave stagnant dead-air pockets at the far end of the void. Those pockets are exactly where humidity builds and fungal decay starts.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Blocked internal walls.<\/b> Sleeper walls and partitions inside the void must be built with sufficient openings so air passes freely from one bay to the next. A void ventilated at the perimeter but sealed internally will still rot.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-722c153 elementor-widget elementor-widget-text-editor\" data-id=\"722c153\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Best practice on anything beyond a simple rectangle is to run ventilation around the full perimeter, which matters most on L-shaped or complex footprints where airflow paths are easily interrupted.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-e552751 e-flex e-con-boxed e-con e-parent\" data-id=\"e552751\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-99407df elementor-widget elementor-widget-heading\" data-id=\"99407df\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">How Much Ventilation You Need\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-98d829c elementor-widget elementor-widget-text-editor\" data-id=\"98d829c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">This is the part DIY guidance usually skips, and it is where the numbers live.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-aa374ae elementor-widget elementor-widget-heading\" data-id=\"aa374ae\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">The Sizing Rule\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0c33da4 elementor-widget elementor-widget-text-editor\" data-id=\"0c33da4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Approved Document C 4.14(b) and NHBC Chapter 5.2 both require void ventilation to whichever of these gives the greater opening area:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-585f9ea elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"585f9ea\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">1500mm\u00b2 per metre run of external wall, or<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">500mm\u00b2 per m\u00b2 of floor area<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9fcdd3b elementor-widget elementor-widget-text-editor\" data-id=\"9fcdd3b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Calculate both, take the larger figure, then fit enough openings to satisfy it. Net free area varies by product, so always work to the certified net ventilation area of the unit you are specifying rather than its nominal size. A typical telescopic underfloor ventilator delivers in the region of 6000mm\u00b2, but some certified air bricks sit nearer 4000mm\u00b2. Underspecifying here is a genuine compliance failure.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7da5289 elementor-widget elementor-widget-image\" data-id=\"7da5289\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"825\" height=\"550\" src=\"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857.png\" class=\"attachment-large size-large wp-image-19267\" alt=\"Sizing Rule\" srcset=\"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857.png 825w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857-300x200.png 300w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857-768x512.png 768w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857-18x12.png 18w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_5_6136162857-600x400.png 600w\" sizes=\"(max-width: 825px) 100vw, 825px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dd745b4 elementor-widget elementor-widget-heading\" data-id=\"dd745b4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">A Worked Example\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-db4a2ac elementor-widget elementor-widget-text-editor\" data-id=\"db4a2ac\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Take a suspended floor measuring 6m by 8m.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4d87579 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"4d87579\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Floor area method: <\/b>6 x 8 = 48m\u00b2. At 500mm\u00b2\/m\u00b2 that is 48 x 500 = 24,000mm\u00b2.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Wall run method:<\/b> perimeter is 2 x (6 + 8) = 28m. At 1500mm\u00b2\/m that is 28 x 1500 = 42,000mm\u00b2.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Governing figure: <\/b>42,000mm\u00b2, because it is the greater.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c6ef5d6 elementor-widget elementor-widget-text-editor\" data-id=\"c6ef5d6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">At roughly 6000mm\u00b2 of certified free area per unit, that is 42,000 \/ 6000 = seven units as a minimum. You then distribute them across opposing walls so the cross-flow works, not bunched on one elevation.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2e87b0c elementor-widget elementor-widget-heading\" data-id=\"2e87b0c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Spacing<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f961626 elementor-widget elementor-widget-text-editor\" data-id=\"f961626\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Spacing is NHBC guidance rather than statute, but it is the working standard the warranty bodies expect:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-061ea97 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"061ea97\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Ventilators at no more than 2m centres.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Positioned within 450mm of the end of any wall.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eb1b516 elementor-widget elementor-widget-text-editor\" data-id=\"eb1b516\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">You can technically hit 1500mm\u00b2 per metre with units at 4m centres, but that wide spacing invites stagnant pockets and is poor practice. Treat 2m centres as the default.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-111f526 elementor-widget elementor-widget-heading\" data-id=\"111f526\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Ducts and the Oversite\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8085fdf elementor-widget elementor-widget-text-editor\" data-id=\"8085fdf\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Two requirements often get missed:f<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b4bc56a elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"b4bc56a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Ducts: <\/b>Any pipe carrying ventilating air should have a diameter of at least 100mm, per Approved Document C 4.14(b).<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Ground covering: <\/b>Approved Document C 4.13 requires the ground beneath the floor to be covered so it resists moisture and prevents plant growth. The oversite works alongside the vents, not instead of them.                    <\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-6beb4a3 e-flex e-con-boxed e-con e-parent\" data-id=\"6beb4a3\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-f06d7af elementor-widget elementor-widget-heading\" data-id=\"f06d7af\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Clearances and Heights: Two Different Sets of Numbers\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7cacb81 elementor-widget elementor-widget-text-editor\" data-id=\"7cacb81\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Heights cause confusion because two separate sets of dimensions are in play, and people merge them. Keep them apart.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1a52ec8 elementor-widget elementor-widget-heading\" data-id=\"1a52ec8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Internal Void Clearance (Approved Document C 4.14b)\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2b3e475 elementor-widget elementor-widget-text-editor\" data-id=\"2b3e475\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">These are the clearances inside the void:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fd4a505 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"fd4a505\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">At least 75mm from the ground covering to the underside of any wall plate.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">At least 150mm from the ground covering to the underside of the suspended timber floor, or to the underside of insulation where fitted.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8d7b05f elementor-widget elementor-widget-heading\" data-id=\"8d7b05f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">External Siting\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-df9a1c4 elementor-widget elementor-widget-text-editor\" data-id=\"df9a1c4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">These govern where the brick sits in the wall face:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0fbf68d elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"0fbf68d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Air bricks should ideally sit around 75mm above finished external ground level, or beside ground that is sloped and draining, so the opening stays clear of soil, debris, and standing water. This is NHBC siting guidance.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">The damp-proof course should sit a minimum of 150mm above adjacent external ground. This is a separate requirement, not the same 150mm as the internal void clearance above.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-90c74b0 elementor-widget elementor-widget-text-editor\" data-id=\"90c74b0\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">The finished ground should always fall away from the wall, never toward it, so water cannot pool against the opening.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-2eeec17 e-flex e-con-boxed e-con e-parent\" data-id=\"2eeec17\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-58a8ad9 elementor-widget elementor-widget-heading\" data-id=\"58a8ad9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Telescopic Air Bricks and Difficult Ground Levels\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a94d1b0 elementor-widget elementor-widget-text-editor\" data-id=\"a94d1b0\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Ground levels are rarely as tidy as the drawings suggest. Patios, raised beds, and built-up paths routinely sit above the point where a vent needs to breathe. Telescopic air bricks, which Approved Document C calls offset or periscope ventilators, are built for exactly this.<\/span><\/p><p><span style=\"font-weight: 400;\">A telescopic vent steps the ventilation path from the void below up to an opening above finished ground level, usually around the DPC line.<\/span><\/p><p><span style=\"font-weight: 400;\">How to get it right:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4c55851 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"4c55851\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">The upper front opening sits above ground where it can breathe.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">The lower rear opening drops to void level and must not be obstructed by the floor construction, or the unit does nothing.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Standard units cover a range of brick courses, with vertical extension sleeves available where the step is greater than the unit's range.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Where flooding is a risk, vertical extensions can raise the intake above expected flood-water level.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-12b479e elementor-widget elementor-widget-text-editor\" data-id=\"12b479e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">One material caution for spec work: most telescopic units are plastic and are not suitable for use in the external walls of high-rise buildings that require non-combustible materials. Check the product data against the project&#8217;s fire requirements before specifying.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6409d7a elementor-widget elementor-widget-image\" data-id=\"6409d7a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"825\" height=\"550\" src=\"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979.png\" class=\"attachment-large size-large wp-image-19277\" alt=\"Air Bricks and Difficult Ground Levels\" srcset=\"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979.png 825w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979-300x200.png 300w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979-768x512.png 768w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979-18x12.png 18w, https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_7_6010781979-600x400.png 600w\" sizes=\"(max-width: 825px) 100vw, 825px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d682590 elementor-widget elementor-widget-heading\" data-id=\"d682590\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Why Blocked Vents Cause Damp\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8d16314 elementor-widget elementor-widget-text-editor\" data-id=\"8d16314\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Here is the failure mode that brings surveyors out time after time. The vents get blocked, and the void stops breathing.<\/span><\/p><p><span style=\"font-weight: 400;\">The causes are predictable:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-55475b6 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"55475b6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Soil, leaves, and garden debris build up against the wall and bury the opening.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">New hard landscaping bridges the vent or the damp-proof course.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Internal insulation, stored rubble, or builders' debris seals the void from inside.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Cement render or careless repointing closes the perforations.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Occupants deliberately block vents to stop cold draughts coming up through the floor, not understanding the consequence.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7443fe6 elementor-widget elementor-widget-text-editor\" data-id=\"7443fe6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Whatever the cause, the result is the same. Airflow stops, void humidity rises, and timber moisture content climbs into the danger zone. Over time that means condensation, mould, wet and dry rot, and in serious cases joists and bearers weakened to the point of bouncy or failing floors.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f07d849 elementor-widget elementor-widget-heading\" data-id=\"f07d849\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Inspection Checklist\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-edaf74f elementor-widget elementor-widget-text-editor\" data-id=\"edaf74f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">When you are assessing an existing property, work through this:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e147d95 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"e147d95\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Locate every vent on all elevations.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Confirm each one is clear of soil, gravel, leaves, and cobwebs.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Check that paths, patios, and raised beds have not been built up to or above vent or DPC level.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Look inside through an access hatch where possible to confirm the void is not blocked by insulation or debris.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">After heavy rain, check whether water is pooling against the wall.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ddd6fa4 elementor-widget elementor-widget-text-editor\" data-id=\"ddd6fa4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Clear blockages by brushing rather than poking hard objects through the perforations. Where ground levels have risen, lower the soil or fit a telescopic unit rather than leaving the opening buried.\u00a0<\/span><\/p><p><a href=\"https:\/\/learn.tradefoxapp.com\/\"><span style=\"font-weight: 400;\"><strong>TradeFox<\/strong><\/span><\/a><span style=\"font-weight: 400;\"> keeps this kind of practical trade knowledge clear and easy to follow, with hands-on learning you can work through at your own pace.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-2aa9e05 e-flex e-con-boxed e-con e-parent\" data-id=\"2aa9e05\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-15cb0cd elementor-widget elementor-widget-heading\" data-id=\"15cb0cd\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The Trade Takeaway\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-37646ca elementor-widget elementor-widget-text-editor\" data-id=\"37646ca\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Air bricks are cheap, simple, and unforgiving when neglected. The regulations give you firm numbers to work to:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-599149c elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"599149c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">The greater of 1500mm\u00b2 per metre run or 500mm\u00b2 per m\u00b2 of floor area.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Units at 2m centres and within 450mm of wall ends.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">A 75mm void below wall plates and 150mm below joists internally, with the brick sited clear of ground level externally.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\">Cross-flow guaranteed across the whole void, including through sleeper walls.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c618552 elementor-widget elementor-widget-text-editor\" data-id=\"c618552\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Specify to those figures, install so the void genuinely breathes, and inspect blocked vents as the first port of call whenever underfloor damp shows up. For anything non-standard, confirm the required opening area with the structural engineer or architect, because the floor area and wall run on your job set the real numbers.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>Underfloor ventilation rarely gets the attention it deserves on site, yet it accounts for a large share of the damp and timber decay surveyors find across UK housing stock. Get it right and the subfloor void stays dry for the life of the building. Get it wrong and you are looking at rot, mould, and [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":19263,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_glsr_average":0,"_glsr_ranking":0,"_glsr_reviews":0,"footnotes":""},"categories":[19],"tags":[1282,1292,1291,1290,430,1288,1286,1284,1285,1287,1283,1289],"class_list":["post-19260","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bricklaying","tag-air-bricks","tag-blocked-vents","tag-condensation","tag-dry-rot","tag-external-wall","tag-ground-moisture","tag-sleeper-walls","tag-subfloor-void","tag-telescopic-ventilator","tag-timber-decay","tag-underfloor-ventilation","tag-wet-rot"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.8 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp<\/title>\n<meta name=\"description\" content=\"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/tradefoxapp.com\/fr\/air-bricks\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp\" \/>\n<meta property=\"og:description\" content=\"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/tradefoxapp.com\/fr\/air-bricks\/\" \/>\n<meta property=\"og:site_name\" content=\"Tradefox | Construction Training Online\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/profile.php?id=61561067514381\" \/>\n<meta property=\"article:published_time\" content=\"2026-06-10T05:12:47+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-06-10T05:16:34+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png\" \/>\n\t<meta property=\"og:image:width\" content=\"825\" \/>\n\t<meta property=\"og:image:height\" content=\"550\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Tradefoxapp\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@Tradefox_app\" \/>\n<meta name=\"twitter:site\" content=\"@Tradefox_app\" \/>\n<meta name=\"twitter:label1\" content=\"\u00c9crit par\" \/>\n\t<meta name=\"twitter:data1\" content=\"Tradefoxapp\" \/>\n\t<meta name=\"twitter:label2\" content=\"Dur\u00e9e de lecture estim\u00e9e\" \/>\n\t<meta name=\"twitter:data2\" content=\"8 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/\"},\"author\":{\"name\":\"Tradefoxapp\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#\\\/schema\\\/person\\\/cad3ebca9b0c18ad17cdf9222b9e4d06\"},\"headline\":\"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp\",\"datePublished\":\"2026-06-10T05:12:47+00:00\",\"dateModified\":\"2026-06-10T05:16:34+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/\"},\"wordCount\":1558,\"publisher\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/imageedit_1_2013882980.png\",\"keywords\":[\"Air bricks\",\"Blocked vents\",\"Condensation\",\"Dry rot\",\"external wall\",\"Ground moisture\",\"Sleeper walls\",\"Subfloor void\",\"Telescopic ventilator\",\"Timber decay\",\"Underfloor ventilation\",\"Wet rot\"],\"articleSection\":[\"Bricklaying\"],\"inLanguage\":\"fr-FR\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/\",\"url\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/\",\"name\":\"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/imageedit_1_2013882980.png\",\"datePublished\":\"2026-06-10T05:12:47+00:00\",\"dateModified\":\"2026-06-10T05:16:34+00:00\",\"description\":\"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#primaryimage\",\"url\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/imageedit_1_2013882980.png\",\"contentUrl\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/imageedit_1_2013882980.png\",\"width\":825,\"height\":550,\"caption\":\"Blocked Vents Cause Damp\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/air-bricks\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/tradefoxapp.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#website\",\"url\":\"https:\\\/\\\/tradefoxapp.com\\\/\",\"name\":\"Tradefox | Construction Training Online\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/tradefoxapp.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fr-FR\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#organization\",\"name\":\"Tradefox | Construction Training Online\",\"url\":\"https:\\\/\\\/tradefoxapp.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/03\\\/logo-transperent.png\",\"contentUrl\":\"https:\\\/\\\/tradefoxapp.com\\\/wp-content\\\/uploads\\\/2026\\\/03\\\/logo-transperent.png\",\"width\":1024,\"height\":208,\"caption\":\"Tradefox | Construction Training Online\"},\"image\":{\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/profile.php?id=61561067514381\",\"https:\\\/\\\/x.com\\\/Tradefox_app\",\"https:\\\/\\\/www.instagram.com\\\/tradefoxapp\\\/\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/tradefox-ltd\\\/\"]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/tradefoxapp.com\\\/#\\\/schema\\\/person\\\/cad3ebca9b0c18ad17cdf9222b9e4d06\",\"name\":\"Tradefoxapp\",\"sameAs\":[\"https:\\\/\\\/tradefoxapp.com\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp","description":"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/tradefoxapp.com\/fr\/air-bricks\/","og_locale":"fr_FR","og_type":"article","og_title":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp","og_description":"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.","og_url":"https:\/\/tradefoxapp.com\/fr\/air-bricks\/","og_site_name":"Tradefox | Construction Training Online","article_publisher":"https:\/\/www.facebook.com\/profile.php?id=61561067514381","article_published_time":"2026-06-10T05:12:47+00:00","article_modified_time":"2026-06-10T05:16:34+00:00","og_image":[{"width":825,"height":550,"url":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png","type":"image\/png"}],"author":"Tradefoxapp","twitter_card":"summary_large_image","twitter_creator":"@Tradefox_app","twitter_site":"@Tradefox_app","twitter_misc":{"\u00c9crit par":"Tradefoxapp","Dur\u00e9e de lecture estim\u00e9e":"8 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/tradefoxapp.com\/air-bricks\/#article","isPartOf":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/"},"author":{"name":"Tradefoxapp","@id":"https:\/\/tradefoxapp.com\/#\/schema\/person\/cad3ebca9b0c18ad17cdf9222b9e4d06"},"headline":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp","datePublished":"2026-06-10T05:12:47+00:00","dateModified":"2026-06-10T05:16:34+00:00","mainEntityOfPage":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/"},"wordCount":1558,"publisher":{"@id":"https:\/\/tradefoxapp.com\/#organization"},"image":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/#primaryimage"},"thumbnailUrl":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png","keywords":["Air bricks","Blocked vents","Condensation","Dry rot","external wall","Ground moisture","Sleeper walls","Subfloor void","Telescopic ventilator","Timber decay","Underfloor ventilation","Wet rot"],"articleSection":["Bricklaying"],"inLanguage":"fr-FR"},{"@type":"WebPage","@id":"https:\/\/tradefoxapp.com\/air-bricks\/","url":"https:\/\/tradefoxapp.com\/air-bricks\/","name":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp","isPartOf":{"@id":"https:\/\/tradefoxapp.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/#primaryimage"},"image":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/#primaryimage"},"thumbnailUrl":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png","datePublished":"2026-06-10T05:12:47+00:00","dateModified":"2026-06-10T05:16:34+00:00","description":"Air bricks keep subfloor voids dry. Trade guide to UK sizing rules, placement, telescopic vents and why blocked vents cause damp.","breadcrumb":{"@id":"https:\/\/tradefoxapp.com\/air-bricks\/#breadcrumb"},"inLanguage":"fr-FR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/tradefoxapp.com\/air-bricks\/"]}]},{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/tradefoxapp.com\/air-bricks\/#primaryimage","url":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png","contentUrl":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/06\/imageedit_1_2013882980.png","width":825,"height":550,"caption":"Blocked Vents Cause Damp"},{"@type":"BreadcrumbList","@id":"https:\/\/tradefoxapp.com\/air-bricks\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/tradefoxapp.com\/"},{"@type":"ListItem","position":2,"name":"Air Bricks: What They Do, Where They Go, And Why Blocked Vents Cause Damp"}]},{"@type":"WebSite","@id":"https:\/\/tradefoxapp.com\/#website","url":"https:\/\/tradefoxapp.com\/","name":"Tradefox | Formation en construction en ligne","description":"","publisher":{"@id":"https:\/\/tradefoxapp.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/tradefoxapp.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"fr-FR"},{"@type":"Organization","@id":"https:\/\/tradefoxapp.com\/#organization","name":"Tradefox | Formation en construction en ligne","url":"https:\/\/tradefoxapp.com\/","logo":{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/tradefoxapp.com\/#\/schema\/logo\/image\/","url":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/03\/logo-transperent.png","contentUrl":"https:\/\/tradefoxapp.com\/wp-content\/uploads\/2026\/03\/logo-transperent.png","width":1024,"height":208,"caption":"Tradefox | Construction Training Online"},"image":{"@id":"https:\/\/tradefoxapp.com\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/profile.php?id=61561067514381","https:\/\/x.com\/Tradefox_app","https:\/\/www.instagram.com\/tradefoxapp\/","https:\/\/www.linkedin.com\/company\/tradefox-ltd\/"]},{"@type":"Person","@id":"https:\/\/tradefoxapp.com\/#\/schema\/person\/cad3ebca9b0c18ad17cdf9222b9e4d06","name":"Tradefoxapp","sameAs":["https:\/\/tradefoxapp.com"]}]}},"_links":{"self":[{"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/posts\/19260","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/comments?post=19260"}],"version-history":[{"count":19,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/posts\/19260\/revisions"}],"predecessor-version":[{"id":19304,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/posts\/19260\/revisions\/19304"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/media\/19263"}],"wp:attachment":[{"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/media?parent=19260"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/categories?post=19260"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tradefoxapp.com\/fr\/wp-json\/wp\/v2\/tags?post=19260"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}