Flat Roof Replacement
Old flat roof past its best? We strip and replace with a modern system built to last.
- EPDM, GRP fibreglass, felt & liquid systems
- New insulation and deck board included where needed
- Fixed pricing — no hidden costs
When Patching Is No Longer Enough
Flat roofs have a finite lifespan. Traditional felt coverings last 10 to 15 years, and even well-maintained systems eventually crack, blister and lose their waterproofing ability. Once multiple repairs are needed or the deck beneath has become soft and saturated, a full replacement is the only reliable solution.
Radiant Roofing carries out complete flat roof replacements across Kent, Sussex and Surrey. We strip back to the joists if necessary, replace any rotten timber, install new insulation and deck board, and lay a modern flat roofing system — EPDM rubber, GRP fibreglass or torch-on felt — that will keep your property dry for decades.
How It Works
Full Survey
We inspect the existing roof, check the deck and timbers beneath, and recommend the best replacement system for your property.
Detailed Quote
You receive an itemised quote covering strip-out, timber, insulation, covering and all finishing details — no surprises.
Complete Replacement
We strip the old roof, replace any damaged timber, install insulation and lay your chosen system to manufacturer specifications.
Guarantee
Your new flat roof is backed by our workmanship guarantee plus manufacturer warranties of up to 25 years on the covering system.
Full Survey
We inspect the existing roof, check the deck and timbers beneath, and recommend the best replacement system for your property.
Detailed Quote
You receive an itemised quote covering strip-out, timber, insulation, covering and all finishing details — no surprises.
Complete Replacement
We strip the old roof, replace any damaged timber, install insulation and lay your chosen system to manufacturer specifications.
Guarantee
Your new flat roof is backed by our workmanship guarantee plus manufacturer warranties of up to 25 years on the covering system.
What Our Flat Roof Replacement Includes
We handle every stage of a flat roof replacement, from strip-out and timber repairs through to the final covering and trim details. All work meets current Building Regulations for thermal performance.
What Does a Flat Roof Replacement Cost?
Typical price range
£1500 – £6000
VAT may apply depending on the project
Factors that affect the price:
- 1Roof area (measured in square metres)
- 2Covering system chosen (felt is most affordable, GRP is premium)
- 3Condition of existing deck and timber structure
- 4Insulation requirements to meet Building Regulations
We provide a fixed, written quote after a thorough survey. Most domestic flat roof replacements — garages, extensions, dormers — are completed within two to three days.
What Our Customers Say
Verified Google ReviewsJane S.
Kent
They were very friendly, professional and polite and left the site immaculate at the end of the day. I would thoroughly recommend them to others. The work was carried out to a very high standard.
Peter B.
East Sussex
Excellent work, highly recommended! Very knowledgeable, by far the best roofing company we have ever used and super nice guys.
Sarah M.
Surrey
Radiant Roofing completed our roof repair quickly and professionally. Great communication throughout and a fantastic result.
Frequently Asked Questions
A flat roof replacement typically costs between £1,500 and £6,000 for a standard domestic roof such as a garage, extension or dormer. The main factors are roof size, the covering system you choose and whether the deck or timbers need replacing. EPDM and felt systems sit at the lower end, while GRP fibreglass is at the premium end. We provide a fixed written quote after survey.
Most domestic flat roof replacements take two to three working days. Larger roofs or jobs that require significant timber repairs may take up to five days. We will give you a clear timeline before work starts and keep you updated throughout the project.
It depends on your property and budget. EPDM rubber is the most popular choice for domestic flat roofs — it is affordable, flexible and lasts 30 to 50 years. GRP fibreglass is the premium option, ideal for balconies or areas with foot traffic. Torch-on felt is a cost-effective choice for garages and outbuildings. We will recommend the best system for your specific situation.
We cover Kent, East Sussex, West Sussex and Surrey. Our teams regularly carry out flat roof replacements in Tunbridge Wells, Crowborough, Sevenoaks, Tonbridge, Uckfield, Haywards Heath, East Grinstead and surrounding areas.
If more than 25% of the roof area is being replaced, Building Regulations require the new roof to meet current thermal performance standards. This usually means adding rigid insulation boards above the deck. We handle this as part of every replacement project and can arrange Building Control sign-off where required.
Contact Us!
Get in touch with us!
Looking for a free quote? Just fill in the form below, and we'll take care of the rest!
Contact Information:
Mobile (24/7): 07753 165 005
Landline (Office Hours): 01892 356 967
Email: contact@radiantroofing.co.uk
Head Office:
Address:
Alpha House
Crowborough Hill
Crowborough
TN6 2EG
Opening Hours:
Monday to Friday: 7:30 am – 6:00 pm
Saturday: 7:30 am – 12:00 pm
Sunday: Closed (mobile still available)
Our Mobile and Email is available 24/7
