★★★☆★☆3.6 on Google from 140+ reviews
FENSA — builders in London
FENSA oversees and certifies businesses in the window and door trade. Homeowners can use its free online search tool to find FENSA Approved Installers by postcode, company name or FENSA ID number, and FENSA handles registering eligible replacement window and door jobs with the local council.
What FENSA does — and what it typically costs in London
Every job below can be priced from this page. The ranges are what London homes typically pay, from Locufy's price guides. FENSA confirms the exact figure in a written quote — asking is free, with no obligation.
Building & extensions
Kitchens, bathrooms & interiors
Roofs, walls & windows
Typical prices from Locufy's UK 2026 price guides — each guide explains what the job involves and what moves the price. Rendering and insulation installer are also offered, priced on survey.
About FENSA
FENSA oversees and certifies businesses in the window and door trade. Homeowners can use its free online search tool to find FENSA Approved Installers by postcode, company name or FENSA ID number, and FENSA handles registering eligible replacement window and door jobs with the local council.
You can ask for a written price on any building job from this page — an extension, a kitchen refit, a roof that leaks — and compare it with other London builders if you want to.
At a glance
- Trade
- Building and construction
- Based
- London
- Covers
- London and 15 km around
- 3.6 · 140+ reviews
- Hours
- Mon–Fri 9:00–17:00
- Quotes
- Written, free, no obligation
A written price, with no obligation
Describe the job
A line or two and a photo if you have one — it takes a minute.
FENSA prices it
Locufy passes it on; they come back to you with a written price.
Book, or compare
Happy? Book the date directly with them. Not sure? Compare quotes from other London builders.
How FENSA is rated
As published on Google, refreshed on each visit.
Read the reviews on Google →Reviews from Locufy bookings appear here
Every Locufy review comes from a job booked through Locufy, so each one is a real customer. Booked FENSA? You can leave the first one after the job.
Have a question before you book?
Do they handle planning? Are they on the voluntary construction register? Ask here — Locufy passes it to them and emails you their answer.
London and the towns around it
Based in London, FENSA works across the city and about 15 km around it.
- London
- Islington
- City of Westminster
- Barking
- Croydon
- Ilford
- Tottenham
- Walthamstow
- Wembley
- Fulham
Before you book
What does FENSA do?
FENSA monitors and certifies local businesses in the window and door industry. Its approved installers are the ones that can issue FENSA certificates.
How can I find a FENSA Approved Installer?
Use the free search tool on the FENSA website and enter your postcode, a company name or a FENSA ID number. You can then request a quote online from the installers you find.
What is a FENSA certificate?
Each FENSA certificate confirms that your window or door fitting meets Building Regulations standards, that the local council has it on record, and that guarantee insurance backs it. Only a FENSA Approved Installer can issue one.
Who registers my replacement window or door job with the council?
A FENSA Approved Installer registers the job with the local council for you. Otherwise, registering replacement window and door installations is the homeowner's responsibility.
Get a written price from FENSA
You can compare it with other London builders too.
·Builders in London·Builder in London·Report this pageIs this your business? No email on file — request to claim →