Description
How to Order — Important Sizing Information
Select your required width and enter your required length in metres. The membrane is priced and sold per linear metre — if you order 4 metres, you receive a single continuous 4m length.
Allow a minimum of 150mm overhang on all edges before trimming. For example, if your roof deck measures 4.0m x 3.0m, order a width of at least 4.30m and a length of at least 3.30m to ensure full coverage and proper edge detailing.
Important: Do Not Lay Directly Onto Existing Felt
EPDM rubber membrane at 1.2mm thickness must not be applied directly onto existing bitumen felt. The two materials are chemically incompatible and can compromise membrane performance. Always install onto a clean, dry, structurally sound timber or board deck — new OSB3 or plywood laid over your existing structure is the recommended approach.
This 1.2mm EPDM rubber roofing membrane is the UK's most widely specified single-ply waterproofing solution for both residential and light commercial flat roofs. Manufactured from high-quality ethylene propylene diene monomer (EPDM) rubber, it combines outstanding flexibility, weather resistance, and chemical stability to deliver a roof that genuinely lasts a lifetime.
Unlike the thinner 1.0mm grade, the 1.2mm membrane meets building regulation requirements and is approved for habitable extensions, garage conversions, and commercial flat roof applications. Available in widths from 0.53m to 9.15m per metre length, and compatible with splice joining tapes for larger roofs, it is the professional roofer's first choice for versatility and long-term reliability.
The membrane is supplied per linear metre, pre-cut to your specified width, and arrives as a single piece — eliminating on-site joining and the leak risk that comes with it. Slate grey in colour, pliable, and straightforward to bond with water-based deck adhesive, it can be installed cleanly and professionally without any hot works or open flame.
Key Features and Performance Benefits
BBA Certified System
Fully certified by the British Board of Agrément — the highest independent endorsement for flat roofing materials in the UK.
Building Regulation Compliant
The 1.2mm grade meets current UK building regulation requirements — suitable for habitable extensions, conversions, and commercial properties.
50+ Year Life Expectancy
Proven track record with documented service lives exceeding 50 years — outperforming felt, bitumen and GRP alternatives by decades.
Compatible With Joining Tapes
Unlike thinner membranes, the 1.2mm grade works fully with EPDM splice joining tapes — enabling leak-free seaming on larger roof areas.
No Hot Works Required
Installed cold using water-based deck adhesive — no torches, flames, or specialist equipment needed. Safer, cleaner, and faster to fit.
UV and Ozone Stable
Specifically formulated to resist prolonged UV exposure, ozone degradation, and extreme temperatures without cracking, peeling, or hardening.
Maintenance Free
Once correctly installed, the membrane requires no ongoing treatment, painting, or coating — only a simple annual visual inspection.
Lightweight and Pliable
Significantly lighter than GRP or built-up systems. The slate grey, pliable rubber drapes naturally over roof features and is easy to trim on site.
Recommended Applications
Flat Roof Extensions
Residential Garages
Garden Rooms and Studios
Garden Sheds and Log Cabins
Dormer Roof Structures
Bay Window Roofs
Porches and Canopies
Flat Roof Repairs and Overlays
Commercial Flat Roofs
Orangeries and Outbuildings
The 1.2mm grade is building regulation compliant and appropriate for both residential habitable spaces and light commercial applications. For heavily trafficked or green roof installations, consider our 1.5mm membrane.
Technical Specifications
| Material Composition | EPDM (Ethylene Propylene Diene Monomer) Synthetic Rubber |
| Membrane Thickness | 1.2mm |
| Colour | Slate Grey |
| Available Widths | 0.53m to 9.15m (select from dropdown) |
| Maximum Length Per Order | 30.5 linear metres |
| Sold As | Per Linear Metre (price shown is per metre of length) |
| Surface Finish | Smooth, Non-Reinforced |
| Temperature Flexibility Range | -40°C to +120°C |
| Minimum Installation Temperature | 5°C (water-based adhesive may freeze below this) |
| Elongation at Break | Greater than 300% |
| Tensile Strength | Minimum 7.0 MPa |
| Tear Resistance | Minimum 25 N/mm |
| Fire Classification | Class E (EN 13501-1) and BS 476 rated |
| Certification | BBA Certified System |
| Installation Method | Fully Bonded using Water-Based Deck Adhesive |
| Seam Joining | Compatible with EPDM Splice Joining Tapes |
| Minimum Roof Pitch | 1:80 (0.7 degrees) — suitable for flat and nearly flat roofs |
| Expected Service Life | 50+ Years |
| Suitable Substrates | OSB3, Plywood, Concrete, Insulation Boards (NOT directly on felt) |
| Chemical Resistance | Excellent resistance to acids, alkalis, ozone, and UV radiation |
| Foot Traffic | Light foot traffic tolerated (installation and inspection only) |
| Environmental Impact | Recyclable, Low VOC, no hot works required |
Installation Overview
This membrane is installed using a fully bonded method with water-based EPDM deck adhesive. Cold application — no torches or flames required. Recommended minimum installation temperature is 5°C.
Prepare the Deck
Install clean OSB3 or plywood decking over your roof structure. Do not apply directly onto existing bitumen felt. Ensure all board edges are flush and all fixings are flush or countersunk.
Dry Lay and Acclimatise
Unroll the membrane across the deck and allow it to relax for at least 30 minutes. Ensure a minimum 150mm overhang on all edges. If the membrane has manufacturer's creases, gently warm and flatten before bonding.
Apply Water-Based Deck Adhesive
Fold back half the membrane and apply water-based deck adhesive to both the deck surface and the membrane underside using a short-pile roller. Allow to tack off (approx. 10–20 minutes depending on conditions and temperature).
Bond and Roll
Carefully lay the membrane onto the adhesive-coated deck, avoiding air pockets. Roll firmly with a heavy rubber roller to ensure full bond. Repeat for the second half of the membrane.
Trim and Finish Perimeters
Trim excess membrane and secure all perimeter edges using compatible drip edge trims, kerb trims, and wall up-stand trims. Apply mastic sealant behind all trim terminations for a fully weather-tight result.
Frequently Asked Questions
Is this suitable for buildings subject to planning permission or building regulations?
Yes. The 1.2mm EPDM membrane is building regulation compliant and BBA certified, making it suitable for habitable extensions, converted garages, and any application where building regulations approval is required. This is the key distinction from the thinner 1.0mm grade, which is better suited to non-habitable structures like garden sheds.
Can it be laid on top of existing roofing?
The membrane must not be laid directly onto existing bitumen felt — the two materials are chemically incompatible. However, you can lay new OSB3 or plywood decking boards directly over your existing roof structure (without stripping the old covering), and then apply the EPDM onto the fresh deck. This saves time and disposal costs while still achieving a correct installation.
Will my membrane arrive with any joins in it?
EPDM membranes are manufactured on large industrial rolls which may contain factory joins from the production process. Your membrane is supplied to you as a single piece cut to your required dimensions — there are no field seams you need to make on-site. For large roofs exceeding the available single-piece width, EPDM splice joining tapes can be used with the 1.2mm grade to create a fully watertight joint.
Should I choose 1.2mm or 1.5mm?
The 1.2mm membrane is the industry standard for the majority of residential and commercial flat roof applications and is our most popular specification. The 1.5mm grade lays slightly more easily due to its additional weight and is recommended where the roof will be overlaid with decking, paving slabs, screed tiles, or a green roof system. Both grades meet building regulations.
Can I install EPDM rubber roofing myself?
Yes — EPDM rubber is one of the most DIY-accessible roofing systems available. No hot works, gas torches, or specialist roofing plant are needed. A competent DIY installer with the correct adhesive, roller, and edge trims can achieve a fully professional result. We recommend reviewing installation guidance before starting and ensuring the substrate is properly prepared.
Is it safe to walk on after installation?
EPDM rubber can withstand light foot traffic, such as during installation and routine inspections. It should not be used as a regularly walked surface without protective boards or walkway pads, and care should be taken to avoid introducing sharp objects (screws, nails, or sharp tool edges) that could penetrate the membrane.
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