What to check before appointing an installer


Meet your
FENSA Advisor

This is Harry.

You might recognise him from our TV ad.

Harry works for a FENSA Approved installation company. He's on a mission to help professionalise installers and protect homeowners across the UK, so he started this advice column.

Before you appoint an installer to replace your windows and doors, ask them: “Will I get a FENSA certificate when the job’s done?” Why? Because their answer to that one, simple question will tell you immediately whether they are right for you.

If they say no, you should say no.


Why? Because a FENSA certificate provides proof that your installer’s work complies with Building Regulations, uses energy efficient products, and is registered with the Local Council (a legal requirement).


Also, it means their warranty is insured (this is the case for all FENSA certificates issued after June 2014). Good to know, in case anything goes wrong and the company is not around to honour their warranty. There are many unprofessional installers out there, so you need to be careful.


Remember, only a FENSA Approved Installer can get you a FENSA certificate. It’s all the proof you need of a job done right.

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What to check before appointing an installer

Check that you use a FENSA Approved Installer but also check the following:

  • Ask family and friends who have used installers about their satisfaction and whether they got a FENSA certificate.
  • Check the installer's references by talking to their previous customers.
  • Get at least three quotes and check you are being quoted like for like.
  • Cheapest is not always best and good contractors are always in demand.
  • Get quotes, timeframes and the fact that you will get a FENSA certificate all in writing. A proper written contract with an agreed completion date will help prevent confusion later on
  • Check the warranty on the installer's work and ensure they have enough insurance to cover their warranty. Domestic glazing installers that are registered with a competent person scheme like FENSA are legally obliged to provide warranty insurance to cover your installation should the company cease to trade within the life of the warranty.
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