What is a PMMA floor?
A PMMA floor is a resin floor based on polymethyl methacrylate — the same acrylic you know as Perspex. Its defining characteristic is curing speed: where epoxy needs a day per coat, a PMMA coat is walkable in about two hours.
That makes it the default choice when downtime costs more than the floor itself: supermarkets, hospitals, kitchens, laboratories, cold stores, parking decks and production lines that must be running again over a weekend or overnight.
How it works
PMMA cures by free-radical polymerisation, started with a powdered catalyst (usually a peroxide). The amount of catalyst sets the working time, and the applicator adjusts it to the ambient temperature. Because the reaction does not depend on warmth the way epoxy does, PMMA can be applied at low temperatures — down below freezing, which almost no other resin system manages.
The build-up typically consists of a primer, an intermediate layer with broadcast quartz sand for slip resistance and thickness, and a sealer coat. Total thickness is usually in the order of 3 to 5 mm; less for thinner coating systems.
Strengths and weaknesses
Strengths:
– Very fast cure, several coats in a single day.
– Workable at low temperatures.
– UV stable — it does not yellow like standard epoxy, so it suits external use on balconies, access decks and parking decks.
– Elastomer-modified grades are crack bridging and follow the thermal movement of the substrate.
– Good chemical resistance and easy to clean.
Weaknesses:
– Strong odour during application and cure. The monomer vapour is penetrating; good ventilation and coordination with occupants or neighbours are essential. The smell disappears once cured.
– Higher material cost than epoxy.
– Short working time: little room for error, and not a DIY job.
Substrate requirements
As with any resin floor, the substrate determines the result. The concrete must be dry enough, free of dust and grease and sufficiently sound in tensile strength; in practice it is shot blasted or ground. A ground-bearing slab without a working damp-proof membrane is unsuitable: rising moisture will push any closed resin layer off sooner or later.
Substrate checks for a PMMA floor
- Concrete dry enough: The concrete must be dry enough.
- Free of dust and grease: The concrete must be free of dust and grease.
- Sufficient tensile strength: The concrete must be sufficiently sound in tensile strength.
- Shot blasted or ground: In practice the concrete is shot blasted or ground.
- Ground-bearing slab: working damp-proof membrane: A ground-bearing slab without a working damp-proof membrane is unsuitable: rising moisture will push any closed resin layer off sooner or later.
Related terms
- Poured floor
- Resin
- Plastic
- Acrylic
- Screed
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