What it costs: Synthetic resin floors

Synthetic resin flooring has been around since the early sixties, usually installed in commercial, industrial, healthcare and educational buildings. It is a hardwearing, versatile, jointless flooring system, which is relatively easy to clean and can be specified to meet enhanced performance requirements.

A problem for specifiers is the huge range and variation of types. The British Standard 8204–6 lists eight, based on thickness and surface finish. There are at least four synthetic resin binder materials and a host of formulations for specific requirements.

The good news is that the choices can be narrowed down by sub-floor type and condition, expected use, environment, construction programme and desired life.

Once you’ve sorted out your requirements, how do you make a choice? Cost may come into it, but beware of differences in formulations, which is a specialist area. Similar sounding products may perform differently because of their constituents.

Use and service life

The thinnest type is a coating applied like a paint by brush or roller. The thicker systems – 2mm to greater than 6mm – are poured over the sub-floor, sometimes in layers. These are more like screeds.

Service life is directly proportional to the thickness of the floor and inversely proportional to the traffic intensity and loads. Substrate quality, cleaning regime, and exposure to damage also influence service life. For example, a 0.3–1mm thick floor has an anticipated life of five to seven years in a light-duty setting, comprising light foot traffic and occasional rubber-tyred vehicles. In a medium-duty application, the anticipated life of the same floor is two to four years, owing to the intensity of regular foot traffic, frequent forklift traffic and occasional hard plastic wheeled trolleys. In theory, a life of 15–20 years and longer can be achieved.

Synthetic resin types

Specifiers may be able to select from one of four different resin types. Epoxy is the most common, and generally comprises an epoxy resin and a hardener. Aromatic hardeners tend to yellow with age unlike aliphatic ones.

Polyurethane resins are one-pack moisture curing systems which offer good abrasion and chemical resistance. They require a good substrate preparation but are generally cheaper than epoxies.

Methacrylate is tolerant of poor substrate conditions and extreme temperatures during curing. It is air curing and can cure fast, which makes it ideal for repairs – loads can be carried two hours after laying. It does, however, have an acrid smell.

Polyester curing is done using a catalyst or accelerator, and can be fast (one to two hours). It is very strong and resistant. Styrene emissions may limit use to new buildings unless good ventilation is possible.

Performance qualities

• Chemical resistance This needs to be checked with the manufacturer. Testing may be required to EN 13529
• UV exposure Resins and pigments may discolour in sunlight or UV radiation
• Slip resistance Floors should have a minimum slip resistance value of 40, based on the BS 7976 test (36-64 indicates low risk)
• Appearance An enormous range of colours and finishes are possible, including terrazzo effect with finishes thicker than 2mm
• Ease of cleaning Smooth, less porous types are easier to clean, but more slippery.

Other variables include fire, impact and wear resistance, static electricity and heat; strength; hardness; shrinkage and swelling.

Design, installation and maintenance

The condition of the substrate is important. In the case of concrete it may mean waiting for the slab to dry to a suitable level.

Joints in the substrate should be matched by joints in the resin floors, especially thicker types. Avoid feather-edging – use toe-in joints at perimeters. Also avoid service penetrations.

Allow adequate time for curing and take precautions to avoid osmotic blistering. It should be installed by a specialist.

It is also advisable to determine a suitable cleaning regime. Spills should be cleared and damage repaired immediately.

The Resin Flooring Association provides selection, design and installation guidance.