Pipe support spacing and thermal movement

110 mm

Horizontal drainage pipes, typically 110mm diameter, require support at regular intervals, often around 900mm to 1000mm centres, or at every joint/socket

Horizontal drainage pipes, typically 110mm diameter, require support at regular intervals, often around 900mm to 1000mm centres, or at every joint/socket. For longer pipe runs (e.g., 5 metres or more), the design must incorporate provisions to accommodate thermal expansion and contraction, preventing undue stress on the system.

Basis in regulation

BS EN 12056-2
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Part H
Approved Document H
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How to check it on site

Confirm that pipe supports are installed at the correct spacing along the run and that provisions for thermal movement are visible on long sections.

Common failure

Insufficient pipe supports lead to sagging and potential blockages, while neglecting thermal movement can cause joint separation or pipe buckling.

Last updated 23 August 2026. This is our editorial summary of publicly available regulation, not building control approval or a warranty determination.

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