01
Know who supplies and installs
- Business identity & trading history
- Relevant windows / doors experience
WINDOWS & DOORS INSTALLER GUIDE
How to check a windows & doors installerbefore you hire.
Practical guidance on product specification, Building Regulations compliance, guarantees, survey and installation handover.
Check a windows & doors installerAt a glance
For replacement windows and doors, pay particular attention to:
02
Check certification & protection
- Building Regulations & self-certification route
- Insurance & guarantees
03
Approve the product & survey
- Product & installation specification
- Survey, measurements & payments
04
Get certificates & snagging clear
- Installation, snagging & certificates
- Written agreement
What to verify
The essentials at a glance.
Open any area to see the detailed checks, questions to ask and what good looks like.
Practical conversations
Questions worth asking
Resolve the responsibilities, assumptions and practical details that matter before work begins.
How will Building Regulations compliance be demonstrated?
Resolve this point before work begins.
Which scheme are you registered with, if self-certifying?
Resolve this point before work begins.
What certificate will I receive?
Resolve this point before work begins.
What exact frame and glazing system is included?
Resolve this point before work begins.
When are measurements signed off?
Resolve this point before work begins.
What is included in making good?
Resolve this point before work begins.
Look for a coherent pattern
Evidence that supports confidence
Look for several consistent signals rather than relying on any one claim or profile.
- Clear contracting identity
- Current relevant self-certification status where used
- Specific product schedule
- Written guarantees
Resolve uncertainty
Things worth investigating
Not automatic failures — prompts to look more closely.
- Certification route unclear
- Generic product description
- Large deposit before final survey
- Guarantee responsibility unclear
Protect the project
Before you agree the work
Turn the check into a clear project agreement.
Clarify product / glazing specification before work begins.
Clarify survey and dimensions before work begins.
Clarify compliance certificate before work begins.
Clarify guarantees and snagging before work begins.
Useful answers
Windows & Doors Installer hiring FAQs
Straightforward answers to common questions about hiring a windows & doors installer.
Do replacement windows need a FENSA certificate?
FENSA is one authorised competent person scheme in England and Wales, not the only route. Relevant replacement work needs the appropriate Building Regulations compliance route; another authorised scheme or building control can also be used.
What paperwork should I keep?
Keep the contract / product specification, relevant Building Regulations compliance certificate and guarantee / warranty documents.
Check before you commit
Ready to check this windows & doors installer?
Check the windows & doors installer's details and get a clearer view of the evidence before you commit.