Fully insured
Guaranteed workmanship
Free no-obligation quotes
35 Firs Avenue, Barnet, London, N11 3NE
Home / Services / Flat Roofing
Flat Roofing in London
Flat roofs are common across London, particularly on extensions, garages, porches, commercial units and converted properties. When they’re installed properly, they provide dependable protection and a clean, practical finish. At RJC Roofing & Building, we carry out flat roof installation, repairs and replacement work across London for domestic and commercial customers.
Our Flat Roofing Services in London
We provide a complete range of flat roofing services, from small localised repairs to full replacement systems. Every job starts with a careful inspection so we can understand the condition of the existing roof, the cause of any leaks and whether repair or replacement is the better option.
Our work includes flat roof repairs, new installations, roof replacement, edge detailing, outlets, flashing, insulation upgrades and repairs around skylights or roof penetrations. We work on garages, rear extensions, dormers, outbuildings, porches and commercial premises.
Where possible, we’ll repair a sound roof rather than recommend unnecessary replacement. If the surface has deteriorated, the deck has become weak or water has been getting in for some time, a new system may offer better long-term value.
What Include
Types of Flat Roofing We Install
EPDM Rubber Roofing
EPDM is a flexible rubber membrane often used on extensions, garages and outbuildings. It provides a smooth finish, handles temperature changes well and can be installed with relatively few joints.
GRP Fibreglass Roofing
GRP creates a hard, seamless surface that works well on many residential flat roofs. It can be finished with neat trims around edges and outlets, making it a popular choice where appearance matters.
Felt Roofing
Modern roofing felt is more durable than older systems and remains a practical option for sheds, garages, porches and larger flat roof areas. Correct preparation and detailing are essential for a reliable result.
Our Process
The RJC Roofing & Building Process
We believe every successful roofing and building project starts with clear communication and careful planning. From your initial enquiry to the final inspection, our straightforward process ensures quality workmanship, complete transparency, and a hassle-free experience every step of the way.
Initial Inspection
We assess the roof covering, deck, drainage, edges and visible signs of water ingress.
Repair or Replacement Advice
We explain whether the roof can be repaired or whether replacement would provide a more dependable solution.
Clear Quotation
You’ll receive a quotation outlining the agreed system, preparation work and any additional repairs required.
Installation
The new roofing system is installed with careful attention to joints, trims, flashing, outlets and upstands.
Installation or Repair
We inspect the finished roof, clear the site and make sure the surface, edges and drainage details have been completed properly.
Expertise
Roofing Experts You Can Trust
Whether you need reliable roofing solutions or want to know why homeowners and businesses across London choose RJC Roofing & Building, you'll find everything here. Explore our professional services and discover our commitment to quality workmanship, honest advice, and exceptional customer care on every project.
Flat Roof Repairs in London
Flat roof leaks often appear some distance from the actual fault. Water may enter around an edge, outlet or split in the covering, then travel beneath the surface before becoming visible indoors.
Common issues include cracked felt, damaged membranes, failed joints, blocked outlets, standing water, loose flashing and deterioration around skylights. We inspect the whole roof rather than only the area directly above the damp patch.
On London properties, access and drainage can make a big difference. A rear extension in Hackney may sit between neighbouring walls, while a garage roof in Barnet or Croydon may need a different approach due to its size, pitch or outlet position.
Why Choose RJC Roofing & Building for Leadwork?
London has a wide mix of roof styles, and many older homes still rely on traditional lead details that have been repaired several times over the years. On Victorian terraces in Islington or Hackney, access can be tight and the leadwork may sit alongside ageing slate. In areas such as Barnet, Ealing and Croydon, extensions and dormers often introduce several roof junctions that need careful waterproofing.
We take a practical approach to each job. Where a local repair is suitable, we’ll explain what can be done. Where the lead has split repeatedly, been incorrectly sized or reached the end of its useful life, replacement may be the more dependable option.
Customers value clear advice, tidy working methods and knowing that the less visible details have been handled properly. We focus on correct preparation, secure fixing and neat finishing rather than simply covering over an existing fault.
Areas
Lorem Ipsum
Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since 1966.
Faq
Frequently Asked Questions
Have questions about our roofing or building services? We've answered some of the most common queries to help you better understand our services, our process, and what you can expect when working with RJC Roofing & Building. If you can't find the information you're looking for, our friendly team is always happy to help.
How do I know if my flat roof needs replacing?
Leadwork is used to seal roof junctions and direct water away from vulnerable areas such as chimneys, valleys, walls, dormers and box gutters.
Can a flat roof be repaired without replacing the whole surface?
Yes. Localised repairs may be possible where the remaining roof is in sound condition. We’ll inspect the full area before recommending the best option.
Which flat roofing system is best?
That depends on the roof size, construction, budget, access and intended use. EPDM, GRP, felt and liquid systems can all work well when used in the right situation.
How long does a flat roof installation take?
Smaller roofs may be completed within a few days, while larger or more complex roofs take longer. Weather, access and the condition of the deck can also affect the timescale.
Why is water pooling on my flat roof?
Standing water is often linked to poor falls, blocked outlets, movement in the deck or an unsuitable drainage layout.
Can you insulate a flat roof during replacement?
Yes. A replacement is often a good opportunity to improve insulation, subject to the roof construction and relevant requirements.
Do you work on commercial flat roofs?
Yes. We undertake flat roofing repairs and installations for shops, offices, outbuildings and other commercial properties.
Get in Touch
If your flat roof is leaking, showing signs of wear or needs complete replacement, contact RJC Roofing & Building. We provide practical advice, professional flat roof repairs and carefully installed roofing systems across London for homes, landlords and commercial properties.
RJC Roofing & Building provides professional roofing and general building services across London. We work with homeowners, landlords and property managers who want clear advice, dependable workmanship and a job completed properly.
Menu
Services
Copyright © 2026 RJC ROOFING & bUILDING. All rights reserved.