There is no single adhesive that's suitable for all types of resilient floor coverings.

The best adhesive for any particular job will depend on a range of factors, including what type of material is being laid, what the substrate is made from and how much wear and tear the floor will be subjected to.

The selection of the most appropriate adhesive is generally made by the floor covering manufacturer and specified in the installation instructions.

However, there are times when the client may have unusual site conditions or requirements, and an alternative adhesive needs to be used.

In these cases, you should always check with the flooring manufacturer before going ahead - otherwise you may find that you've voided the warranty conditions.

Below are the main categories of adhesives used with sheet vinyl installations.

Note that with the continuing development of new chemical compounds and combinations of compounds, some products may fall into more than one category.

Epoxy

Epoxy resins are two part reactive adhesives. That is, when the separate components are mixed together they set off a chemical reaction.

They are classified as hard set adhesives because they crystallise to form a non-flexible bond.

This gives them a high peel strength, meaning that the floor covering does not peel away easily from the substrate.

But their shear strength is not as good, which means that they are less resistant to forces that tend to slide one layer against another.

This can be a problem in areas where there might be movement in the subfloor, such as on steel floors around gantry cranes.

However, they have excellent water and chemical resistance, and can withstand high temperatures.

These adhesives are used in wet areas, commercial kitchens, bars and areas subject to high levels of traffic.

Polyurethane

Most polyurethanes are also two-part adhesives that cure due to a chemical reaction between the components, although there are some one-part products.

They are classified as semi-soft set, because they remain reasonably flexible and are able to withstand subfloor movements.

Polyurethanes have excellent sheer and peel strength.

They come in a wide range of brand names and are a popular choice for most resilient floor installations.

Like the epoxy resins, they are widely used in commercial applications and wet areas.

Acrylic

There are many acrylic adhesives on the market.

Most are solvent based or water based, which means that the curing action occurs when the solvent or water evaporates after the adhesive is applied.

They can be one or two part adhesives and are classified as soft set and semi-soft set.

Although their bond strength is excellent, they are generally water soluble, which makes them unsuitable for use in wet areas.

Acrylics generally have a longer open time than other adhesives and are non-toxic and non-flammable.

They are also highly resistant to plasticiser migration (see the next lesson for details on this problem).

Contact

Contact adhesives have a solvent, neoprene or water base and are classed as soft set.

The adhesive is applied to both surfaces and allowed to dry before the two surfaces are brought together.

When the surfaces contact each other the bond is instant.

This makes them suitable for use on vertical surfaces, such as vinyl skirtings and covings.

Note that the adhesive is not waterproof, so the exposed edges must be sealed to stop water penetration.

Looking to the future

In recent years there has been an enormous amount of research into new formulations for adhesives.

The challenge has been to find products that are less damaging to the environment and the health of installers who use them.

The main problem for scientists has been that many of these more 'environmentally friendly' water based products are less effective than the adhesives they are designed to replace.

However, new products are being developed, trialled and brought onto the market all the time.

One example is 'Envirostix', a poly-acrylic adhesive system manufactured by Base King.

Follow the link below for more information about this product and the issues that they are aiming to overcome.

Envirostix