Gas
Pipe and installation volume
- where
- total installation volume (m³)
- internal pipe diameter (m; any unit you pick is converted)
- developed pipe length (m)
- meter, fittings, appliances and other sections (m³; any unit you pick is converted)
Explain this equation
Estimates the internal volume of a gas installation: the pipe plus the meter, fittings and other sections. The volume is used to decide test and purge procedures under the applicable method.
d is the internal bore, which governs how much gas the pipe holds. L is the developed length. V_other is everything else in the system you need to include, such as the meter and other pipe sections, entered as verified volumes.
A pipe is a long cylinder, so its volume is the cross-sectional area π × d² / 4 times its length. The calculator shows that pipe section in litres, then the total in m³.
Sense check: 10 m of 20 mm bore holds about 3.1 L. Adding 3 L of other volumes gives about 0.0061 m³. Doubling the bore makes the pipe volume four times larger.
Watch out: use internal bores, not nominal sizes. This does not work out test durations, permitted drops or purge volumes.
Enter your values to see the result.
Good to know
Use internal bores and verified additional volumes. IGEM/UP/1B Edition 4 applies from 1 October 2026; this tool does not calculate permitted pressure drop, purge quantity, test duration or a tightness-test pass.
Sources
Results are arithmetic only. Worked examples are not recommended design settings. This library does not provide automatic gas pipe selection, live gas tightness tests, purging procedures, combustion acceptance limits, installation approval or commissioning certification. Manufacturer data and the applicable current method remain essential.