The Federation of Master Builders

FMB Building Work Guarantee for Builders

Published date: 05 July 2024

We all know sometimes the unexpected can happen on a job. FMB Building Work Guarantee* is an insurance backed guarantee that offers you peace of mind, covering the cost of any work that needs to be rectified to protect not only the homeowner, but you as the builder, for up to 10 years.

Our policy covers a huge range of projects, including extensions, loft conversions, general building work and more. But where the FMB Building Work Guarantee differs from others on the market, is that we cover all aspects of the build under one policy. So it’s easy to explain to your clients, and doesn’t leave any component of the project without cover.

*This policy is administered by FMB Insurance, which is authorised and regulated by the Financial Conduct Authority.



Essentially, it’s an insurance policy that helps homeowners if there are problems with the quality of the work after your business is no longer operating – for example, if you've retired, or are suffering from an illness and you can't fulfil the written guarantee. 



If there are defects found in the completed work after a project is finished, and your business is no longer in operation, the FMB Building Work Guarantee steps in.

It covers the reasonable cost of fixing these defects, sticking to the original contractor's guarantee and insurance policy terms, up to the original contract price. This ensures your clients' investment is protected and keeps your reputation strong.



If you’re a member of the FMB, you’ll be able to access FMB Building Work Guarantee at a lower price. That’s because our strict vetting and inspection process on joining means you can ensure you can complete each job to a high standard.

To find out more about joining the FMB or to start your application today, go online or call the FMB on 0330 822 5224 (Mon-Fri 9am-5pm)



If you’re registered with TrustMark, you can benefit from our lowest prices when you buy an FMB Building Work Guarantee. As a member of the scheme, you have an obligation to provide an insurance backed guarantee for all work, and our 2-year FMB Building Work Guarantee complies with TrustMark’s Framework Operating Requirements.

How to join TrustMark: Builders can join TrustMark though licenced scheme providers, like the FMB. Find out more about registering with TrustMark on the FMB website.



The possibility of things going wrong with your work can be a tricky subject to broach with your clients. But to your them, it demonstrates that you’re thinking ahead, and that you can show an ongoing duty of care. Their investment in home improvement is safe in your hands.

Including FMB Building Work Guarantee when you quote for work can:

- Show you offer a quality service

- Strengthen your aftercare offering

- Help you to win more work



Our FMB Building Work Guarantee is available as a 2, 6, or 10 year policy, commencing from the date of completion and is available on a wide range of home improvement projects, including: 

  • General Building
  • Extensions
  • Porches
  • Loft conversions
  • Roofing
  • Piling / Underpinning 
  • Kitchens
  • Bathrooms
  • Conservatories 
  • Local Authority Grant Works

Whatever changes your client wants to make to their property, they can benefit from an FMB Building Work Guarantee to give them full protection on their investment, after completion. 



Do I need to provide this cover?

You don’t need to, but it is recommended. It’s a great way to give your customers’ peace of mind that the work is fully covered, should anything go wrong.

Additionally, certain organisations such as competent person self-certification schemes; and certain trade bodies may- as part of their scheme rules and membership terms- require that you provide insurance backed guarantees to your customers.

How do I get a quote?

You can contact the FMB Insurance team on 01353 652760 to run through a quote, email [email protected] or request a quote online by visiting 

How much is the excess?

The excess for our Building Work Guarantee is £50.


An FMB Building Work Guarantee is more than just financial safety. In a tough market, offering IBGs makes you stand out, giving you a competitive edge and building trust. This extra security could be what signs the dotted line—especially since homeowners are taking extra precautions before committing to home improvement projects.

For more information on how an insurance backed guarantee can benefit you, contact the FMB Insurance team at 01353 652760 or email [email protected].


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