When replacing or buying a new window or door, you want to choose an installer that you can trust.

But how can you tell that an installer is fully qualified for the job? 

Window and door accreditations are there to offer peace of mind for homeowners when employing a window or door installer. 

Window and door accreditations certify that an installer is qualified and helps ensure a quality installation, whilst also helping provide proof of quality of the products used.

So, which window and door accreditations should you look for when choosing an installer? 

In this article, we take a look at some of the window and door accreditations and what they mean for you. 


Window and door accreditations



TrustMark is a government-backed quality scheme that indicates that a company operates to government endorsed standards and are technically qualified to perform the installation.

A TrustMark Registered Company has been strictly vetted and has shown that it has made considerable commitments to implementing good practices and being technically competent. 

What does this mean for you? 

When you see the TrustMark logo, you know that you are getting a quality service from a qualified installer. 



FENSA stands for Fenestration Self Assessment Scheme.

If an installer is FENSA approved then this shows that they comply with building regulations and are continually monitored to ensure that this remains the case.

To get technical, FENSA is a Competent Person Scheme. 

FENSA accreditation is a sure-fire way for installers to show their products comply with current building regulations. 

What’s more, FENSA approved means that the installer’s guarantees are backed by insurance, providing that extra peace of mind.



GGF is the Glass and Glazing Federation that represents companies that supply or manufacture glazing products in the UK or internationally. 

In order for companies to join the GGF, they must first pass a strict vetting process, which includes a GGF expert visiting and inspecting a company’s premises.

How does this help you? An installer that is GGF approved provides products that their customers can rely on, knowing that they have been thoroughly vetted to ensure they comply with high standards.

For more information and advice, GGF has launched a consumer support site, MyGlazing, for any queries you may have so you can make informed decisions on all things window, doors, and conservatories. 


An accredited window and door installer 

It is easy to be confused and fooled by all the accreditations that installers promote. 

Now when you are choosing a trusted window or door installer, you know just some of the accreditations to look out for. 

Kettell Windows are FENSA and TrustMark certified and also a member of the GGF. 

You can be rest-assured that an installation from Kettell Windows is an installation that is dependable. 

We take pride in delivering a quality service, supplying and installing the finest products.

If you’re looking for a reliable window or door installation in Leicestershire, get in touch or request a quote today.