Our Services
Perlini specialises in seamless flat roofing across London and England using the Ultraflex system - a fully bonded, cold-applied waterproofing solution that’s rainproof in 30 minutes and guaranteed for 20 years.
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. We may also recommend a survey to be carried out — view a sample flat roof survey report.
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 |
New flat roof installations with Ultraflex typically work out far more cost-effective than traditional strip-and-replace builds. Use our instant estimator for a personalised price for your project.
Why Ultraflex — FAQs
The most common questions we get asked about the Ultraflex cold-liquid waterproofing system.
How long does a new flat roof installation take?
A domestic extension or garage roof is usually two to four days from set up to handover, including preparation and detailing. Larger commercial roofs are phased in sections, with each section left fully watertight at the end of each working day.
Do I need planning permission for a new flat roof?
Replacing an existing flat roof like for like does not normally need planning permission, though it does need to meet current Building Regulations for thermal performance where the roof is over a heated space. New extensions, roof terraces and any work on a listed building or in a conservation area are a different matter and should be checked with your local authority.
What insulation is required on a flat roof?
Where the roof covers a heated room, the build-up must meet the current Building Regulations U-value requirement, which in practice means a substantial thickness of rigid insulation as a warm roof above the deck. We specify the correct thickness for your build-up and confirm it in the quotation.
Can you install in winter or in poor weather?
In most conditions, yes. The resin can be applied down to around freezing on the main roof area and slightly below on details, and it is rainproof in as little as thirty minutes. That makes the installation programme far more predictable through a British autumn and winter than torch-on felt or fibreglass.
Can you install over my existing flat roof?
Wherever the deck and insulation are dry and sound, yes, and it is usually the option we recommend. Overlaying removes strip-out and disposal costs and means the building is never left open. Where the insulation is already saturated we will identify it at survey and price for cutting out those areas first.
What guarantee comes with the finished roof?
A twenty-year guarantee covering both materials and workmanship, issued on completion after our own final inspection, along with a photographic record of the detailing carried out during the installation.
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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