Taking on a self-build project is one of the most exciting ways to create a truly personalised home. With the support of experienced bespoke builders or through managing it yourself, the end result is a home built entirely around your lifestyle. But with such a large investment of time, money, and energy, protecting your build from unexpected risks is essential. That’s where self-build site insurance and a structural warranty come in.

If you're wondering whether you really need both or what makes them different, read on — especially if you're working with bespoke construction services or acting as your own property developer.

How a Self-Build Structural Warranty Works

A self-build structural warranty is an insurance policy that covers your new bespoke custom build during construction and for ten years after completion. The main difference between this and a standard warranty is that you — the self-builder or bespoke builder — are responsible for arranging it, rather than a developer passing it on.

Whether you’re building the home yourself or hiring a bespoke construction company like Mosaic Bespoke, you’re considered the developer and are therefore responsible for this critical protection.

The warranty provider will inspect your bespoke build at key stages. Once completed, the warranty covers any hidden structural defects for ten years. For the first two years, your contractor is typically liable. After that, the warranty provider handles claims.

A strong structural warranty covers issues caused by design faults, substandard workmanship, or defective materials — all separate from home insurance, which you’ll need once you move in.

Is Self-Build Site Insurance Necessary Too?

Still wondering if a self-build warranty is necessary? Here are five reasons every bespoke construction or developing house project should have one in place:

1. Essential for Financing
   Planning to finance your build? Every lender will require a structural warranty. Without it, getting a loan for your bespoke custom build will be nearly impossible.

2. Easier Future Sale
   Selling your home within ten years? Any buyer’s mortgage lender will want a valid warranty. It boosts your property’s value and appeal — a smart move for any house builder or aspiring property developer.

3. Avoid Costly Retrospective Policies
   While you can get a warranty after starting the build, it will be classified as retrospective — harder to secure and more expensive.

4. Independent Protection
   Don’t rely on the contractor’s insurance — that protects them, not you. Your own warranty ensures your bespoke build is covered regardless of who is at fault.

5. Peace of Mind
   Structural issues can lead to serious stress and legal costs. A warranty allows you to resolve problems quickly, without litigation — especially valuable in complex bespoke building services.

The Importance of a Self-Build Structural Warranty

Yes — and it’s just as crucial. Whether you’re self-managing or hiring a bespoke home builder, site insurance protects your project during construction.

You should arrange self-build site insurance when you purchase the land, well before construction begins. As the project lead, you’ll need:

• Employers’ Liability Insurance (legally required): Covers injuries to workers on-site.

• Public Liability Insurance: Covers third-party injuries or accidents on the property.

• Contract Works Insurance: Covers the cost of repairs if the build is damaged during progress.

• Tools and Equipment Cover: For all plant, tools, and materials — owned or hired.

Lenders also typically require proof of self-build insurance, with minimums such as:

• £5 million Public Liability

• £10 million Employers Liability

• Full reinstatement value

• Their interest listed on the policy

Whether you're managing your bespoke constructions or working with a bespoke builder, this policy is non-negotiable.

When’s the Right Time to Set Up Your Warranty?

Aim to secure your self-build structural warranty several weeks before construction starts. This allows the provider to inspect key milestones during your bespoke construction project.

Site insurance covers you while building is underway. Once your bespoke build is complete, the structural warranty takes over, protecting you from expensive structural issues for ten more years.

Conclusion

A self-build structural warranty is a must for anyone creating a bespoke home, whether you’re building it yourself or working with a trusted bespoke construction company. Alongside site insurance, it protects your investment and gives you confidence throughout the project.

At Mosaic Bespoke, we specialise in bespoke building services and have helped countless clients navigate the journey from dream to reality. From securing the right warranties to delivering exceptional craftsmanship, we’re here to make your developing house journey smooth, safe, and successful.

Your dream home deserves expert protection. With Mosaic Bespoke, you get so much more than a builder — you get a partner.