Lee FlecknellEmergency roof repairs, rental property · August 2026
Highly recommend this company carried out some emergency roof repairs on one of my properties would use again.
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Garage roof replacement
Garage roof replacement for leaking flat and sheet roofs
Garage roof replacement is one of our most booked jobs, because a leaking garage ruins everything stored in it. Best Top Roofing strips the failed roof, whether that is old felt or a corrugated sheet roof, replaces the deck, and fits a new EPDM, GRP or felt flat roof with proper trims across Hertfordshire and Northamptonshire.
Most garage roofs on 1960s and 70s estates were built to a budget: a single layer of felt on chipboard, or corrugated sheets bolted to timber purlins. Fifty years on, the felt is covered in moss and split along the laps, the chipboard has turned to mush at the edges, and the sheet roofs are cracked, brittle and letting water in at every fixing. The photograph at the top of this page is a typical garage roof before we replaced it.
For flat garage roofs we strip back to the joists where needed, fit a new deck and lay EPDM rubber, GRP fibreglass or torch-on felt with new trims and a fall to the gutter. For sectional and prefab garages with sheet roofs, older corrugated sheets can contain asbestos cement, so we tell you at the survey if the sheets need testing and removing by licensed specialists before we fit the new roof.
A new garage roof protects what you keep in it and, if the garage is attached, the house wall next to it. It is also a small job that makes a big difference when you come to sell.
When you call, you speak to the familyBest Top Roofing is family-run. The family that answers the phone and gives you the quote is the family that turns up and does the job.
What is included
- Survey of the roof, the joists and the fascias
- Old felt, chipboard or sheet roofing stripped and removed
- Asbestos sheets identified and referred for licensed removal where needed
- New joists or firrings where the structure needs it
- New OSB3 deck
- EPDM, GRP or torch-on felt covering
- New edge trims, fascia and gutter
Signs you need this
- Water on the garage floor after rain
- Moss and plants across the roof
- Sagging between the joists
- Cracked or broken corrugated sheets
- Rotten fascia boards at the front edge
Garage roofs: our recent work
Every photo is one of our own jobs. Tap to enlarge.
After: the same garage with a new felt flat roof and trims
GRP fibreglass flat roof at the laminate stage, before the topcoat goes on
How it works
Survey
We check the roof, its structure and what the old sheets are made of.
Fixed written price
Stripping, deck, covering and trims itemised.
Strip and re-deck
The old roof removed, the structure repaired and a new deck laid.
New roof
EPDM, GRP or felt laid, trims and gutter fitted, site cleared.
Garage roofs are quick jobs for us and a big relief for customers. Most are done in a day or two.
Garage roofs: your questions answered
How much does a garage roof replacement cost?
It depends on the size of the garage, the condition of the joists and the covering chosen. A single garage is a modest job; our flat roof cost guide gives typical ranges, and we give a fixed written price after a look.
Does my garage roof contain asbestos?
Corrugated cement sheet roofs on older garages can contain asbestos. Felt roofs on timber decks do not. If we suspect asbestos we tell you before any work and arrange for it to be tested.
What is the best roof for a garage?
EPDM rubber is our usual recommendation for a garage because it is a single sheet that lasts for decades. Felt is the budget option and GRP suits garages you want to use as a terrace.
How long does it take?
A single garage is usually one day, occasionally two if the joists need work. Double garages and attached garages with flashings take a little longer.
Can you replace the fascia and gutter at the same time?
Yes. It makes sense to renew rotten fascias and fit a new gutter while the roof is open.
Related services
Reviews
What customers say on Google
Dannie SmithQuoted the next day · June 2026
Thomas came and gave me a quote next day, very professional and clean work was carried out. I will be using best top roofing for all my projects going forward and would highly recommend them.
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R Vidya RLeaking felt roof repaired · September 2026
thanks to Thomas for fixing our roof. It was pleasure working with you. I feel confident that the water leak is accessed from all points and all problem addressed
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Lee SextonNew flat roof · April 2026
I needed a new flat roofing doing and this amazing company did it exactly how I wanted it. Highly recommended. Friendly and polite. Would use and again and tell all my friends and family.
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Mahmoud Al SuwwanRoof problem fixed · August 2026
We had a problem in our roof we called this company and they solved the problem so happy and satisfied. I really highly recommend if anyone needs roofing work done if I ever need a roofer again hopefully we don't if I ever did I will always use this company again, thank you so much, guys.
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Lisa DunneBlocked gutters cleared · April 2026
Cleaned out our gutters as were blocked and overflowing. Very happy with the job done. Thank you very much!
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Ligita KaledaiteChosen over other quotes · July 2026
Very friendly. Had couple of Quotes from other companys And this was the best company for it.
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Sally MaskellRoofing work by Thomas · June 2026
Very impressed with the work that Thomas has done. Definitely recommend.
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Scarlet BullRoofing work · August 2026
Professional, good quality work! Recommended.
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Checkatrade customerBalcony roof installation · August 2026
Fantastic, professional and polite throughout the job.
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10 year
re-roof
guarantee
Our guarantee
re-roof
guarantee
Every new re-roof guaranteed for 10 years, in writing
When we replace your roof, our workmanship is guaranteed for 10 years from the day we finish, and the membrane, tiles and slates carry their manufacturers' guarantees on top. Repairs and flat roofs are guaranteed too, with the terms for your job written on your quote. We are fully insured.
Covered
- Our workmanship on every new re-roof for 10 years
- Lead, flashings, ridges and verges we fit
- Flat roofs laid to the system's specification
- Repairs, with the terms written on the quote
On top
- Tile and slate manufacturer guarantees
- Membrane and flat roof system guarantees
- Photos of the finished job
- The same family to call if anything is wrong
Not covered
- Storm or accidental damage after completion
- Work altered or added by someone else
- Parts of the roof we did not work on
- Gutters left to block and overflow
The guarantee for your job is written on your quote before you agree to anything. Read the full guarantee.
Talk to us about garage roofs
Ring or send the form. We come out, look at the roof, show you what is needed and give you a fixed written price. No pressure and no hidden extras.