8 January 2023

The importance of site insurance for home extensions

A simple green outline of a house, featuring a triangular roof and a rectangular chimney against a white background.
By Self Build Zone
Aerial view of a house with a partially built roof next to a construction site containing building materials.

Making sure you're covered

Embarking on a home extension can be the start of a very daunting journey, especially if you’re not familiar with the design, planning, and build stages. There’s so much to factor in, from agreeing architectural and structural drawings, navigating your way through the complicated planning system, and of course, the build itself. But have you considered site insurance to protect your home extension project?

Most people will hire a main contractor (builder) and agree a contract alongside a budget. A project manager may be brought in to oversee these different stages, but not all these professionals will be aware of the specific type of insurance you should have in place at the beginning of a house extension project. Very often, the questions around site insurance are raised when a problem is encountered, for example weather damage, arson or tool and plant theft.

Adding site insurance to the cost of your extension might not be something you’ve either thought about or made a priority for your upcoming project. But you can’t just rely on your standard building insurance to cover the cost of any loss as, often, they will not pay out on a loss involving a property under development.

Your builder may say they are ‘fully insured’ – and they probably believe it themselves –but it’s likely they only have public liability insurance which covers them in the event they cause damage or injury to a third party following a negligent act, which of course you would have to prove. Liability insurance doesn’t cover issues like storm damage, arson, theft of materials or plant and equipment or foreseen liability — essentially all the things you really do need to protect yourself against.

Many prospective house extenders will assume their extension will be covered under their existing home insurance; however, these policies are not designed to cover building projects. They specifically exclude alterations, renovations and extensions, as well as cover for unoccupied properties. This has been regularly highlighted in the media when in one case, a couple’s build project was completely destroyed by fire and their home insurer refused the claim. Or, when basement extensions or work on terrace houses cause the buildings to collapse through inadequate workmanship, possibly affecting the neighbouring properties – when site insurance is absent, this leaves the homeowners in very dire positions as they are not covered to pay for rebuilds.

What sort of extension site insurance policy should I look for?

First, you need to check the insurance you are going to buy is backed by A-rated insurers. Your policy will need to cover your whole property while it is being improved or extended, even if you aren’t initially living there, which may be the case with an extensive renovation project. You should also make sure the policy covers all the new works and materials, right up to completion of the project.

You should also opt for a package where tools and equipment left on site are also protected, and employers’ and public liability insurance is included. This means that anyone working on site is covered if they suffer an injury, or if damage is caused to a third party or their property.

What’s more, with the right insurance policy, should anything happen to a worker or family member while on-site during the construction, the cost of defending or pursuing a claim is covered.

You should also consider purchasing a Structural Warranty, which is a lender requirement in the UK; if you are using a lender to fund your build or you wish to sell the property to someone using a mortgage, you will need a 10 10-year structural Warranty.

You can find the perfect self build site insurance with Self-Build Zone by browsing our specific project policy information here.

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