Guide
Do You Need a FENSA Certificate for Replacement Windows or Doors?
A cautious guide to certification routes for replacement windows and doors.
Useful detail
FENSA is one route
FENSA is a Competent Person Scheme route for many qualifying replacement window and door projects. It is not the only route and it does not cover every project type.
Measured survey before final order
Checked before work proceeds so the quote, product and installation route stay realistic.
Photos and plans help early pricing
Checked before work proceeds so the quote, product and installation route stay realistic.
Compliance route agreed before installation
Checked before work proceeds so the quote, product and installation route stay realistic.
Planning note
Other routes may apply
Some projects use another scheme or Building Control. This is especially important for fit-only work, unusual projects, new openings or work outside a scheme scope.
Measured survey before final order
Checked before work proceeds so the quote, product and installation route stay realistic.
Photos and plans help early pricing
Checked before work proceeds so the quote, product and installation route stay realistic.
Compliance route agreed before installation
Checked before work proceeds so the quote, product and installation route stay realistic.
Planning note
Our wording until verified
We advise on the correct certification route for your project, including Competent Person Scheme or Building Control where required.
Measured survey before final order
Checked before work proceeds so the quote, product and installation route stay realistic.
Photos and plans help early pricing
Checked before work proceeds so the quote, product and installation route stay realistic.
Compliance route agreed before installation
Checked before work proceeds so the quote, product and installation route stay realistic.
Planning note
How to use this guide before ordering
Use this as an early decision filter, not a substitute for a measured survey. The right route depends on the opening, property type, product system, access, ventilation, safety glazing, threshold or sill detail, and who is responsible for compliance paperwork.
check the opening before choosing a product
Checked before work proceeds so the quote, product and installation route stay realistic.
confirm supply-and-fit or fit-only route early
Checked before work proceeds so the quote, product and installation route stay realistic.
keep drawings, photos and supplier paperwork together
Checked before work proceeds so the quote, product and installation route stay realistic.
do not order purely from rough measurements
Checked before work proceeds so the quote, product and installation route stay realistic.
Planning note
What to send for project-specific advice
For advice tied to a real property, send postcode, inside and outside photos, rough sizes or plans, access and parking notes, whether building work is underway, and any supplier drawings if products have already been chosen. This helps avoid generic answers and reduces wasted survey time.
Measured survey before final order
Checked before work proceeds so the quote, product and installation route stay realistic.
Photos and plans help early pricing
Checked before work proceeds so the quote, product and installation route stay realistic.
Compliance route agreed before installation
Checked before work proceeds so the quote, product and installation route stay realistic.
Planning note
Proof and compliance note
We advise on the correct certification route for your project, including Competent Person Scheme or Building Control where required. Guide content is general advice and should not be read as a guarantee of availability, price, certification route, local office presence or suitability for a specific supplied product until the project evidence has been checked.
Measured survey before final order
Checked before work proceeds so the quote, product and installation route stay realistic.
Photos and plans help early pricing
Checked before work proceeds so the quote, product and installation route stay realistic.
Compliance route agreed before installation
Checked before work proceeds so the quote, product and installation route stay realistic.
Quote checklist
What to send for a useful first answer
The first quote conversation is faster when the message shows the opening, access and responsibility route. These details also help us avoid giving advice that falls apart at survey.
postcode if the question is project-specific
Include this if you have it. If not, send photos first and we can tell you what still needs checking.
photos of the existing windows, doors or opening
Include this if you have it. If not, send photos first and we can tell you what still needs checking.
rough sizes or plans if available
Include this if you have it. If not, send photos first and we can tell you what still needs checking.
whether you need supply & fit or fit-only
Include this if you have it. If not, send photos first and we can tell you what still needs checking.
any deadline, builder programme or access constraint
Include this if you have it. If not, send photos first and we can tell you what still needs checking.
Next steps
Useful related pages
Building Regulations guide
Open the related page for more detail before requesting a quote.
Get a measured quote
Open the related page for more detail before requesting a quote.
Certification guide
Open the related page for more detail before requesting a quote.
Fit-only installation
Open the related page for more detail before requesting a quote.
Questions
Common questions
Is this guide a fixed quote or survey result?
No. It is early guidance only. A reliable recommendation or final price depends on measurements, photos, product details, access and compliance checks.
Can I use this before buying windows or doors online?
Yes, but supplied products still need drawings, dimensions, delivery details, opening photos and a clear certification responsibility check before fit-only work is accepted.
Can you do fit-only work?
Often, subject to checks. We need product details, photos, measurements, delivery status, access information and a clear agreement about certification responsibilities before accepting fit-only work.
Do you give fixed prices online?
We can explain cost factors and give early guidance, but a reliable final quote depends on measurements, access, product specification, finishing requirements and compliance route.
Do you handle certification?
We advise on the correct certification route for your project, including Competent Person Scheme or Building Control where required.
Quote route
Send photos, postcode and rough sizes.
We can give better early guidance when we can see the opening, existing frame, access and finish expectations.
Proof status
Launch copy stays cautious until project proof is verified.
This page is structured for preview and internal review. Real photos, supplier details, reviews, insurance wording, guarantee terms and accreditation use should be added only when Alex has verified the evidence and usage rights.
Real project photos
Required before stronger public claims or final launch-ready copy.
Verified reviews
Required before stronger public claims or final launch-ready copy.
Supplier/product preferences
Required before stronger public claims or final launch-ready copy.
Guarantee wording
Required before stronger public claims or final launch-ready copy.
Accreditation status
Required before stronger public claims or final launch-ready copy.