New-build home insurance: what the warranty covers and what it doesn't

Buy a new build and you get a 10-year structural warranty with it — usually from the NHBC, or from Premier Guarantee, LABC, or a similar provider. That leads a lot of new owners to the same question: if the house is already under warranty, do I need home insurance for a new build at all?

The short answer is yes, and the reason is that a structural warranty and home insurance cover almost completely different things. Here's exactly where the line falls.

What the 10-year structural warranty actually covers

An NHBC Buildmark warranty (and its equivalents) is a defects guarantee, not an insurance policy. It splits into two phases:

Years 1–2 — the builder's responsibility. The developer must fix defects caused by not building to the warranty's technical standards: faulty plasterwork, a leaking roof, dodgy wiring, tiling that wasn't done properly.
Years 3–10 — the structural cover. The warranty provider steps in for major damage to the structural parts of the home — foundations, load-bearing walls, roofs — where a genuine building defect is to blame.

The key word is defect. The warranty pays out when something goes wrong because the house was built badly. It's there to protect you against the builder's mistakes.

What the warranty does not cover — and why you still need insurance

Your structural warranty will not pay a penny if:

A fire, storm, or flood damages the building.
A pipe bursts and wrecks the ceilings and floors.
Someone breaks in and steals your belongings.
Your sofa, TV, laptop, or clothes are damaged or stolen.

None of those are building defects, so none of them are the warranty's problem. That's the gap buildings and contents insurance fills, and it's why a new build under warranty still needs cover:

Buildings insurance covers the structure against fire, flood, storm, subsidence, and burst pipes — the everyday disasters a defects warranty was never designed for. If you have a mortgage, your lender will require this from the day you exchange contracts, warranty or not.
Contents insurance covers everything you own inside the home. The warranty covers the building's bricks; nothing covers your possessions unless you insure them yourself.

Put simply: the warranty covers the builder's workmanship, and insurance covers real-world accidents and theft. You need both.

One new-build quirk worth knowing

New builds can sometimes be cheaper to insure — modern wiring, new locks, and up-to-date plumbing all lower the risk. But insure the property for its rebuild cost, not its purchase price. On a new build the two can differ sharply, and your warranty documents or the ABI's BCIS calculator will give you the rebuild figure.

How the Aviva ChatGPT app helps

Once you know you need buildings and contents cover, the next step is a quote. The Aviva ChatGPT app gives you a home insurance quote without leaving ChatGPT. When you're ready to buy, you complete your purchase on aviva.com.

To try it, install it from the ChatGPT App tab (or go to chatgpt.com/apps), search "Aviva", and ask a question in your own words — for example, "What would buildings and contents insurance cost for a new-build 3-bed house in Reading still under its NHBC warranty?"

FAQ

Do I need home insurance on a new build if it's under warranty? Yes. The warranty only covers structural defects caused by how the house was built. Fire, flood, theft, and damage to your belongings aren't defects, so you still need buildings and contents insurance for them.

Does the NHBC warranty replace buildings insurance? No. Mortgage lenders require buildings insurance as a condition of the loan regardless of any warranty, because the warranty won't pay out for the everyday events buildings insurance is built for.