Building Extension Insurance

If your home extension hits extensive problems, our insurance can help

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Extending a property not only gives you more living space but it can also greatly increase its value. If you’re happy where you are but need more room, it makes financial sense to opt for a building extension rather than looking for a new home altogether.

Renovation work can take several months and is notorious for getting messy – particularly if you’re knocking down walls or underpinning foundations. So, whether you’re opting for a self-build or you’re hiring a team of trusty professionals, it’s important to have the right building extension insurance in place. This will ensure you’re protected throughout the renovation, so you can plough ahead with peace of mind.

What is building extension insurance

Having the right home extension insurance in place means you’ll be covered against risks that otherwise wouldn’t be covered by your contractor’s insurance policy. The level of risk you’ll be covered for will depend on the level of cover you choose.

Also referred to as self-build extension insurance in some instances, it allows you to have complete peace of mind knowing that you’ll be covered for unforeseen costs that come from these risks.

What does home extension insurance cover?

Home extension insurance protects your property, all the new works taking place and any people on site – from start to finish. Be wary that many standard home insurers won’t cover the property in question during extension works. Renovation and extension insurance plugs this gap, giving you comprehensive cover while your project is underway.

Rear, side or front extension

Whether you’re extending the back, side or front of your property, it’s likely your home insurer won’t cover the structural works involved. That’s where Renovation Plan comes in, with building extension insurance that covers this for you.

Extending up into the loft

While many loft conversions can be carried out without planning permission, standard insurance is unlikely to cover the work taking place. When you choose our building extension insurance, you don’t have to worry. You can rest easy knowing this covers everything from the existing structure to all new works, plus any fixtures and fittings once they’re delivered to the site.

Flat roof extension insurance is something else you may need to consider, depending on what your project involves.

Basement extensions

If you’re planning a basement extension, you’ll require specialist cover. Our range of home extension insurance policies can protect you for all works involving underpinning and piling, with the additional benefit of covering neighbouring semi-detached or terraced properties too.

Why do I need building extension insurance?

While planning an extension is exciting, we know that even the best-laid plans can sometimes go wrong. Whether you’re rolling up your sleeves and opting for a self-build extension or employing contractors to do the work for you, there are countless risks involved that you should consider. These can include stolen equipment and on-site injuries.

All extension projects involve a degree of structural work, which means your standard home insurer is unlikely to cover you. This is also true for your builder’s insurance, which is designed to protect them and not you. Not having the correct building extension insurance policy in place will leave your property vulnerable throughout the entire building works.

That’s why we’re here. Our trusted renovation and extension insurance effectively replaces your home insurance for the duration of your project, keeping both your extension and the rest of your property protected under one straightforward policy.

Your choice of cover level

We offer three levels of building extension insurance cover to suit your needs:

  • Standard – offering essential protection against limited risks
  • Premier – providing a wider range of cover, suitable for small to medium-sized projects
  • Premier Plus – covering ‘All Risks’ and best for larger, more complex renovation projects.

Find out how each level of cover compares.

How do I get building extension insurance?

We understand that every project is unique, which means that the extension insurance cost will be provided on a case-by-case basis. Simply speak with our approachable team to get started.

Before we can offer you a tailored quote, we need the following details to help us find the right cover for you:

  • Your project start date
  • A description of the works
  • How long the works are expected to take
  • The overall costs
  • Details regarding the existing structure

Why choose building extension insurance from Renovation Plan?

With almost two decades of experience as renovation and extension insurance brokers, we’re well-placed to match you up with a policy that works for you. For more information, check out our reviews on Feefo from past customers.

Our policies range from 3-36 months and we can even provide insurance if work on your extension has already started. Plus, if you don’t make a claim and finish ahead of schedule, we’ll refund the time left on your policy (subject to a £25 cancellation fee).

To get in touch with our friendly team, send us an email at or give us a call on 01621 784840.

Ready to get building extension insurance?

FAQs about building extension insurance

Will my builder be covering this work?

Your builder should have at least £2m Public Liability insurance to cover any damage they cause. But if something happens that isn’t their fault – such as fire, flood, escape of water, theft and impact – their policy won’t cover it as their negligence cannot be proven. That’s why you need extension insurance, making sure you’re fully protected in such circumstances.

I have existing buildings insurance; will they not cover this new part of the property?

Once the extension is complete with all fixtures and fittings installed and it’s been signed off by building regulations (if needed), only then will your home insurer cover the extension. But don’t forget that during the construction period, your existing insurer will most likely apply a works exclusion to the policy. This leaves your home and your new extension at risk. The right extension insurance policy will help to bridge any gaps.

My extension will not be weatherproof/watertight for part of the build; will this be a problem?

Don’t worry. We understand that an extension may not be completely weatherproof and watertight part-way through a build, so this isn’t a problem. Just be aware that during this time, there may be certain restrictions applied depending on the level of extension insurance cover you go for.

How much does home extension insurance cost?

The cost of your building extension insurance depends on various factors, such as the type of work you plan to carry out, how long the project is estimated to go on, and the level of cover you choose. We’ll always ask you a few need-to-know questions before we can find the right policy to cover your building extension.

When should I take out insurance for extension work?

Like with other renovation insurance, you should take out an extension insurance policy in the planning stages of your project before any work has started.

Do I need to tell my home insurance provider about my extension?

If you plan to make substantial changes to your home, you’ll need to let your home insurance provider know. If you don’t, your policy could become invalid. It may be that you need to give a certain amount of notice, so check your policy details.

How is my home insurance affected when building an extension?

You need to make your home insurance provider aware of an upcoming extension because your property will be exposed to structural and security risks while the work takes place. Depending on your policy, you may not be covered against certain risks, which is where extension insurance can help.

Once your extension is complete, you may have to pay more for your buildings insurance, which forms part of your home insurance. This is down to the increased square footage in your home. The contents insurance element of your home insurance may also increase depending on how you furnish your extension.

Our 3 levels of cover

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