Smartseal installs glass-reinforced polyester (GRP) flat roofs: a single, hand-laid, fully bonded layer of fibreglass and resin. No felt, no bitumen patchwork, no annual resealing. It is a genuine upgrade on the systems most flat roofs still rely on.
GRP, also known as fibreglass, is a base resin reinforced with chopped-strand matting and finished with a pigmented topcoat, laid over a solid 18mm OSB3 deck. The result is one continuous waterproof surface with no joints, seams or laps, which is exactly where felt and rubber roofs tend to fail. Lightweight, walkable and low-maintenance, it suits everything from a small garage roof to an entire commercial flat deck.
Before
After
Our Smartseal systems maintain the structural integrity of your building without adding excessive weight.
By eliminating weak points like joins and corners, our roofs offer superior protection against leaks and dampness.
Choose from a variety of colours to ensure your roof complements your property perfectly.
Unlike bitumen, our roofs remain stable in all weather conditions, resisting expansion, bubbling, contraction and cracking.
Our roofs provide added safety and durability, offering protection against fire and UV damage.
Suitable for various buildings, from historic houses to new builds, and for architecturally challenging projects.
Here is a Smartseal GRP roof in cross-section. Tap any blue marker on the diagram to see what that part does and why it matters.
The coloured, UV-stable surface you see, available in 92 BS4800 colours with a smooth or non-slip aggregate finish.
Tap a marker on the diagram to explore each part.
With 92 British Standard (BS4800) colours to choose from, you can match render, brickwork, fascias or a neighbouring roof precisely. Tap any colour below and it expands so you can see it properly.
The standard pigmented topcoat. Clean, modern and easy to keep clear of debris. Ideal where the roof is mainly seen, not walked.
A sanded or aggregate finish for balconies, walkways and any roof that needs grip underfoot, without losing the seamless waterproofing.
Whether you need a standard flat roof or complete water containment, Topseal conforms to virtually any shape or size of build, with specifications tailored to the job.
Swatches are a guide. Here is the finished article: the same seamless GRP, in two very different colours.
Felt and EPDM rubber are common on flat roofs because they go down quickly. But they do not match fibreglass for durability or lifespan.
A correctly laid GRP roof is one bonded skin with nothing to lift, split or peel, backed by our written 25-year guarantee.
GRP has become popular, which means inexperienced builders attempt it and occasionally give the system a bad name. Done properly it is exceptional. Done badly it fails early. The difference is the installer. The most common mistakes we are called out to fix:
A Smartseal director attends every survey, and our installers do this and only this. With Topseal and Restec accreditations behind us, you get the system installed the way the manufacturers intend.
Accredited & approved
A director will visit, measure up and talk you through colours and finishes. No pressure, no follow-up sales calls.