Plumbing material checklist for a new home
Plumbing failures are expensive because they are behind tiles. Getting the specification and the pressure test right is nearly the whole job.
Last updated: 28 May 2026 · 6 min read
Supply lines
CPVC for hot and cold supply — SDR 11 where pressure and temperature are higher. Typically 15–20 mm at fixtures, 25 mm on risers. Match fittings to the same brand and system as the pipe; cross-system solvent joints are a leading leak source.
Drainage
PVC SWR: 110 mm for soil, 75 mm for waste, with proper traps, vents and cleanout access. Slope matters — too flat and it blocks, too steep and the liquid outruns the solids.
Valves and concealed bodies
This is where to spend. A concealed diverter or stopcock that fails means breaking a finished wall. Buy quality here even if it means economising on the visible fixture, which is easy to change later.
Pressure test before plaster
Cap the lines and hold test pressure for the duration your plumber specifies, and inspect every joint. This single step catches almost everything that would otherwise appear six months after handover.
The takeaway
Match pipe class to duty, keep the fitting system single-brand, spend on concealed valves, and pressure test before plastering.
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