Moving Into a New Build? A Plumbing Checklist for New Homeowners
Your Day-One Plumbing Checklist
Run through these six checks on the day you move in — before the boxes go everywhere — and note anything wrong for your snagging list.
Find Your Stopcock
Before anything else, locate the internal stopcock — usually under the kitchen sink or in a utility cupboard. Turn it off and on once so you know it works and is not seized. In a real leak, every second you spend hunting for it is water across your new floors.
Check Water Pressure at Every Tap
Run each tap and shower in turn. New builds usually run on mains-pressure combi or unvented systems, so flow should be strong and even. Weak pressure at one outlet often points to a partially closed isolation valve or debris caught in an aerator from the build.
Test Hot Water Everywhere
Confirm hot water reaches every tap and shower within a reasonable time, and that the temperature is steady. Fluctuating hot water on a combi can mean the boiler needs commissioning checks or a flow rate that the developer should put right.
Flush and Watch Every Toilet
Flush each toilet twice. Check it refills and stops cleanly with no continuous trickle into the bowl — a running fill valve is one of the most common new-build snags and wastes a surprising amount of water.
Look Under Every Sink
Open the cabinet under each basin, sink and the boiler, and look for damp, drips or water marks at the push-fit joints and isolation valves. Run the tap for a minute and look again — slow weeps only show under flow.
Bleed and Feel the Radiators
Turn the heating on and check every radiator heats evenly. Cold patches at the top mean trapped air that needs bleeding; cold at the bottom can mean the system needs balancing. Both are normal in a new system and quick to sort.
Common New-Build Plumbing Snags
None of these are unusual, and most are quick to fix. Catch them early and they stay small.
Weeping Push-Fit Joints
Modern new builds use plastic push-fit pipework, which is fast to install but can be left not quite fully seated. A joint that weeps slowly behind a kitchen unit or under a bath can go unnoticed until it stains the ceiling below. Catch it early on your day-one checks.
Weeping Radiator & Isolation Valves
As a new system pressurises and settles, valve glands can seep. A quarter-turn or a new olive usually cures it. Left alone, a steady drip from a radiator valve will mark new flooring and skirting.
Running or Slow-Filling Toilets
Cheap builder-grade fill and flush valves often arrive slightly misadjusted, causing a constant trickle or a slow refill. They are inexpensive to adjust or replace and worth fixing promptly to keep your water bill down.
Airlocks & Banging Pipes
Trapped air causes spluttering taps, noisy filling and the occasional "water hammer" knock when a tap shuts. Bleeding the system and securing loose pipe clips usually settles it down within the first few weeks.
Unlagged Pipes in Lofts & Garages
Developers sometimes leave pipework in cold lofts, garages or external runs without insulation. In a Devon cold snap these are the first to freeze. Lagging them is cheap and prevents a burst pipe in your first winter.
Low Flow from Aerators
Bits of debris from the installation — PTFE tape, plastic shavings, grit — often collect in tap aerators and shower heads. Unscrewing and rinsing them usually restores full flow without needing any parts.
Who Fixes What: Warranty vs Plumber
One of the most confusing parts of a new build is knowing who to call. Here is a quick guide.
The Developer
Anything on your snagging list reported within the defects period (typically the first 2 years): leaking joints, faulty valves, poorly fitted sanitaryware, heating that was never commissioned correctly, and workmanship defects. Report these in writing and keep a record.
The NHBC / Warranty Provider
Most new builds carry a 10-year structural warranty (NHBC or similar). Years 1–2 are usually the developer's responsibility; years 3–10 cover major structural defects only — not everyday plumbing wear and tear.
The Boiler Manufacturer
Your boiler's 5–10 year warranty covers the appliance itself — but almost always only if it is serviced annually by a Gas Safe registered engineer. Book that first service before the anniversary of your move and keep the records.
A Local Plumber (You)
Out-of-warranty repairs, upgrades and additions: fitting an outside tap, plumbing in a washing machine or dishwasher, adding a water softener, upgrading taps and showers, or any fast fix you would rather not wait on the developer to schedule.
Warranty terms vary by developer and provider — always check your own paperwork and home information pack for exact cover and reporting deadlines.
New-Build Plumbing FAQs
Need a Plumber for Your New Home?
Whether it is a snag the developer missed, an upgrade you want straight away, or your first boiler service, browse our directory of local plumbers covering Exmouth and East Devon.
Live in Devon's newest town? See our Cranbrook plumber page. Keep your home in good shape with our annual maintenance checklist. Worried about a leak? Read the signs of a hidden water leak. Frozen or burst pipe? Follow our burst pipe guide. And don't skip that first boiler service — it keeps your warranty valid.