EPDM Flat Roof Alternative
EPDM rubber is a solid flat roof option - but Ultraflex is better. We install Ultraflex over new decks or existing EPDM, asphalt, felt, bitumen, concrete and single-ply roofs to create a fully bonded, seamless waterproof layer with no joints, no laps and a 20-year guarantee.
The problems with EPDM rubber roofs
EPDM is a single rubber sheet laid loose or partially bonded - which means its waterproofing depends entirely on adhesive seams, glued edges and dressed upstands, all of which fail long before the rubber does.
Seams and laps are the weak point
Every join is bonded with tape or adhesive. Over time these seams lift, peel and leak - the rubber itself can outlast the glue holding it together.
Shrinkage pulls the membrane apart
EPDM contracts as it ages, pulling away from upstands, drains and edge trims and exposing the deck beneath.
Ponding and weather damage
Loose-laid sheets settle unevenly, creating ponding spots. Standing water, frost and UV degrade the surface and any exposed adhesive.
Difficult around complex detailing
Pipes, rooflights, corners and upstands all need separate flashings and bonded cuts - the more detail, the more potential failure points.
Repairs rarely match the original
Patching shrunken or contaminated EPDM is hit-and-miss; failed seams often mean re-doing whole sections rather than a clean repair.
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Why we install our waterproofing system over EPDM
EPDM is a loose-laid or partially bonded rubber sheet - its weak points are the seams, edges and upstands, which are typically the first places to leak. Our waterproofing system is fully bonded across the entire surface with zero seams, wrapping every detail in one continuous waterproof layer for the life of the roof.
One of the best flat roof waterproofing systems on the market
Whatever flat roof job you have - installation, repair, replacement, Asphalt, GRP, EPDM or torch-on felt overlay - we install the Ultraflex cold-liquid waterproofing system. It's the most durable, cost-effective, and reliable flat-roof solution available.
By overlaying your existing roof with Ultraflex, we save you the cost and disruption of a full strip-out while delivering a fully bonded, seamless waterproof layer backed by a 20-year guarantee. We go in, repair your existing roof and seal it for decades of protection - if needed, we can apply bespoke finishes and solutions post-waterproofing.
Why we install Ultraflex on every job
Faster installation
Fast-curing and rainproof in as little as 30 minutes.
Up to 50% cost savings
Overlay your existing roof and avoid strip-out costs.
20-year guarantee
Proven waterproofing built for long-lasting protection.
100% Compatible
Torch-on felt, asphalt, GRP, timber, concrete, and virtually any roof surface.
Safer installation
Cold-liquid application, eliminating fire risk.
Seamless waterproofing
No joints or laps - a fully bonded waterproof layer.
How we work:
Instant Estimate
Fill out our cost estimate tool to receive a fast, ballpark price based on your project details. It's a quick way to understand likely costs before moving forward.
Site Visit + Detailed Quote
We carry out a site visit where needed to assess your roof in detail, then provide a clear, itemised quote with no hidden costs so you know exactly what to expect.
Installation
Our trained team prepares the surface and installs the Ultraflex system, delivering a seamless, fully bonded waterproof finish built to last.
Sign-off & 20 Year Guarantee
We inspect the roof, hand over your 20-year guarantee documentation, and leave the property spotless.
How Ultraflex compares
See how our Ultraflex cold-liquid waterproofing system stacks up against traditional flat roof systems across the things that matter most.
| Criteria | Ultraflex | GRP | EPDM | Asphalt | Torch-on Felt |
|---|---|---|---|---|---|
| Seamless, fully bonded | |||||
| Cold-applied (no flame) | |||||
| Rainproof in 30 minutes | |||||
| Overlay existing roof | |||||
| 20-year guarantee | |||||
| Cost-effective long-term | |||||
| Resists cracking & shrinking | |||||
| Suitable for complex detailing |
Ultraflex is competitively priced against EPDM and avoids strip-out costs when overlaying an existing roof — often saving up to 50%. Get a personalised estimate using our calculator.
Why Ultraflex — FAQs
The most common questions we get asked about the Ultraflex cold-liquid waterproofing system.
How long does an EPDM rubber roof last in the UK?
Manufacturers commonly quote twenty years or more for the rubber itself, and on a simple single-sheet roof that is realistic. In practice the working life is set by the bonded seams, upstands and edge details, which frequently need attention somewhere between year ten and year fifteen on a roof with any complexity to it.
Can you waterproof over an existing EPDM roof?
Usually, yes. After cleaning, checking adhesion and applying the correct primer for a rubber substrate, we can apply the liquid system directly over EPDM, sealing failed seams and upstands under one continuous membrane. Where the rubber has shrunk badly or the insulation beneath is wet, we will recommend removing the affected areas first.
Why is my EPDM roof leaking when the rubber looks fine?
Because the rubber is rarely the problem. Look at the seams between sheets, the glued upstands where the roof meets a wall, the corners, the edge trims and the collars around pipes and outlets. Those are adhesive-dependent details, and they age faster than the membrane. Shrinkage of the sheet over time puts all of them under tension.
Is a liquid system more expensive than EPDM?
The installed cost is broadly comparable on a new roof, and often lower where we can overlay an existing covering rather than strip it out. Since the liquid system removes the seams and adhesive details that generate most mid-life EPDM repair bills, the whole-life cost is typically lower.
Which is better for a roof with rooflights and pipework?
A liquid system, clearly. Every penetration in an EPDM roof needs a separate cut, collar or preformed corner bonded into place. A liquid membrane is applied wet around the actual shape of the detail, so the waterproofing at a pipe or kerb is exactly the same continuous membrane as the rest of the roof.
Does ponding water damage the roof?
It does not damage the cured resin membrane, which is fully water resistant and unaffected by standing water. It does affect adhesive-bonded systems, and it always encourages silt and moss that can block outlets, so we assess falls and drainage at survey and recommend building up local falls where the ponding is severe.
Services tailored to your flat roof, we work on any job.
From new installations and full system refurbishments to targeted leak diagnostics and repairs, every project is carried out by our in-house specialists using premium, manufacturer-approved liquid waterproofing systems.
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