Flat Roofing in Oxfordshire
If your flat roof is leaking, holding water, or showing signs of wear, you need a fix that deals with the cause, not a patch that fails again. We provide flat roof inspections, repairs, replacements and new installations across Oxfordshire for homeowners and property managers, with straightforward advice and tidy workmanship from start to finish.
Enquire now














Our Flat Roofing Services in Oxfordshire
Our Services
About Our Flat Roofing Work in Oxfordshire
Across Oxfordshire, we often work on flat roofs for extensions, garages and older properties where original felt systems are now reaching the end of their life. We also see flat roofs fail early where drainage was never formed correctly, leading to ponding after heavy rain, or where edges and upstands were rushed and start to lift over time. Many Oxfordshire flat roof problems come down to the same issues, ageing coverings, weak detailing, and water not being directed away properly. Our work focuses on fixing those weak points properly so the roof performs as it should.
1,000
Project Completed
97%
Customer Satisfaction
40+
Years of Experience
Flat Roofing Systems We Work With
The best flat roof system depends on the roof’s size, access, exposure, and whether it needs to handle regular foot traffic. We work with a range of flat roofing materials and will recommend the most suitable option for your property based on a proper inspection.
EPDM Rubber Roofing
EPDM is a durable rubber membrane that works well on many residential flat roofs such as extensions and garages. It handles movement without cracking and performs reliably in UK conditions when installed with correct preparation and secure edge detailing.
GRP Fibreglass Roofing
GRP fibreglass roofing creates a seamless, hard-wearing finish that suits many smaller flat roofs and areas where a tougher surface is useful. Applied correctly, GRP forms a strong waterproof layer and provides a clean, tidy finish around edges and detailing.
Torch-On Felt Roofing
Modern torch-on felt is a practical option for certain flat roofs when installed correctly with proper layering and clean detailing. The base preparation and edge finishing matter a lot, and done right, felt systems can be dependable and cost-effective.
Liquid Roofing Systems
Liquid roofing systems can be suitable where the roof has complex detailing or where an overlay approach is appropriate. They form a seamless waterproof coating and can be effective when installed with correct primers, reinforcement and curing conditions.
Why Homeowners Across Oxfordshire Choose Alliance Roofing?
People choose Alliance Roofing because we’re straight with them. We inspect the roof properly, explain what’s wrong in plain terms, and give realistic options based on the condition of the roof, not guesswork. We focus on the details that stop repeat leaks, drainage, seams, edges and upstands, and we keep the site tidy and respectful while the work is being carried out.
1,000
Project Completed
97%
Customer Satisfaction
40+
Years of Experience
Trusted Roofing Services Across the
South East
Known across Oxfordshire for reliable workmanship and clear, practical advice
Removal of Chimney stack, replacement of roof underlay, guttering and flat roof repair. - Mitchell from Alliance Roofing & Building was the only builder, of many that I had contacted, that climbed a ladder to inspect my flat-roof and to climb into my loft-space to inspect the main roof from the inside. After an extensive review of my property and discussing my options, he emailed me his quotation on the same day. Booking in dates for Alliance & Roofing to commence work was quick and effortless. They arrived on time, completed the work as planned to a professional standard. Provided Photos of work carried out at all stages. I highly recommend Alliance Roofing & Building.
New roof on my bungalow - I recently had the pleasure of working with Alliance Roofing and Building to install a new roof on my bungalow, and I couldn't be more satisfied with the results. From start to finish, the entire process was smooth and professional. Mitchell, who led the project, was exceptional. His expertise and dedication were evident from the moment he arrived. He and his team were not only highly skilled but also incredibly helpful and courteous throughout the entire job. They took the time to answer all my questions
New slate roof - Mitchell and his team installed my new roof and I'm very satisfied. The quality is superb, they were professional, punctual, and communicative. The project finished on time and the site was left spotless.
Guttering repair - Mitchell came to repair my guttering, he was on time, polite, efficient and conscientious. He kept me informed at each stage of the work that was needed.
Roof repairs - Mitchell repointed a chimney and installed a chimney cowl. He also did some cementing work to the roof. Mitchell was very polite and a conscientious worker. He kept me informed throughout the job. Mitchell was able to give me a quote and do the repair work within a few days. I wouldn’t hesitate to recommend Alliance Roofing & Building.
Replacement of flat roof - Mitchell and his team are smart, communicative, skilled, friendly, helpful, trustworthy and reliable. I would highly recommend their roofing services.
Roof tile replacement and chimney repair - Mitchell and his team are reliable, efficient and hard working. We will certainly use them again in the future. Thanks guys
Chimey Removal & Other Minor Repairs - Mitchell was the only roofer who quoted for the job that actually took the time to go up on the roof to inspect the issue, which was appreciated at the time. He fitted us in around other jobs within 2 weeks to get the work done in a timely manner. The work (which included the removal of a chimney stack to below the roof line, repointing the ridge line, and various other patch repairs) appears to have been completed to a good standard (posting days after completion). Mitchell and his team were polite, conscientious and happy to help throughout the job.
Fixed the roof, including all the felting and repaired the chimney. - Good communication throughout. Good work. Very happy with the service.
Roof repair - Great, really friendly and nice team
Tile realignment/repair and felt renewal - Mitchell and his team were excellent. Would definitely recommend Alliance. The team were on time (in fact they were able to begin the job half a day earlier than initially discussed), polite, efficient and kept us informed of progress each day. We could not have asked for a better service.
Roof verge repair. - Mitchell was polite, friendly and knowledgeable. The team were polite and efficient. The work was completed for the price quoted, which was competitive, and in the timeframe advised.
repair of box gutter behind parapet wall - Mitchell undertook a detailed diagnosis of the work required, started the job quite quickly and completed it satisfactorily.
Leak in the roof- Very polite and professional. Job was completed professionally at a very good price. Would highly recommend
New slate roof - Mitchell and his team installed my new roof and I'm very satisfied. The quality is superb, they were professional, punctual, and communicative. The project finished on time and the site was left spotless.
Roof repairs - Mitchell repointed a chimney and installed a chimney cowl. He also did some cementing work to the roof. Mitchell was very polite and a conscientious worker. He kept me informed throughout the job. Mitchell was able to give me a quote and do the repair work within a few days. I wouldn’t hesitate to recommend Alliance Roofing & Building.
Roof tile replacement and chimney repair - Mitchell and his team are reliable, efficient and hard working. We will certainly use them again in the future. Thanks guys
Chimey Removal & Other Minor Repairs - Mitchell was the only roofer who quoted for the job that actually took the time to go up on the roof to inspect the issue, which was appreciated at the time. He fitted us in around other jobs within 2 weeks to get the work done in a timely manner. The work (which included the removal of a chimney stack to below the roof line, repointing the ridge line, and various other patch repairs) appears to have been completed to a good standard (posting days after completion). Mitchell and his team were polite, conscientious and happy to help throughout the job.
Fixed the roof, including all the felting and repaired the chimney. - Good communication throughout. Good work. Very happy with the service.
Roof repair - Great, really friendly and nice team
Tile realignment/repair and felt renewal - Mitchell and his team were excellent. Would definitely recommend Alliance. The team were on time (in fact they were able to begin the job half a day earlier than initially discussed), polite, efficient and kept us informed of progress each day. We could not have asked for a better service.

We assess the roof’s condition, identify the cause of any issues, and talk you through the options clearly so you can make a sensible decision.

We provide a straightforward quotation explaining what’s included. Once agreed, we book in the work around what’s practical for you and the job.
.png)
We complete the work with careful detailing and watertight finishes, then carry out final checks so you’re not left hoping it’s been done properly.
Frequently Asked Questions
If the issue is localised and the structure is sound, a repair can often solve it. If the roof has widespread cracking, repeated leaks, sagging, or the covering is at the end of its lifespan, replacement is usually the safer long-term option. An inspection will confirm which route makes sense.
Leaks are commonly caused by failed seams, cracked coverings, damaged edges, or blocked outlets that lead to standing water. Leaks can also start around upstands, rooflights and weak detailing.
Minor repairs can often be completed in a day. Replacements and larger installations depend on roof size, access and the system being installed. After an inspection, we’ll give you a realistic timescale.
Persistent ponding can shorten the life of a flat roof and increase the chance of leaks. It’s usually a sign the roof falls or drainage need attention, or that the structure has moved over time.
In many cases, yes, but it depends on the weather and the system being used. Some materials require dry conditions for best results. If urgent, we can advise on the safest way to make the roof watertight and plan the permanent fix.
It depends on how the roof is used, the condition of the existing surface, and the level of exposure. EPDM, GRP, felt and liquid systems all have their place. After inspecting your roof, we’ll explain the most suitable options and why.

.png)
.png)
.png)
.png)
