Making resilient flooring installations capable of withstanding damp and humid conditions means choosing floorcoverings and adhesives based on how much water they will be exposed to says Jason Tatton, one of F. Ball and Co. Ltd.’s technical service officers.
Water that is allowed to get beneath resilient floorcoverings can attack adhesives, causing floorcoverings to blister and de-bond and damage subfloors that are sensitive to moisture, such as chipboard. Ultimately, this may result in costly floor failure and recalls.
Key to preventing floor failure in these situations is using suitably moisture resistant adhesives and floorcoverings (which depends on how much water they will be exposed to), as well as proper subfloor preparation.
Subfloor preparation
Before proceeding with any floorcovering installation, make sure that the subfloor is suitably sound, smooth and free of any surface contaminants, including old adhesive residues and non-moisture tolerant smoothing underlayments and primers.
In accordance with British Standards, we recommend the use of a pre-calibrated digital hygrometer to measure the relative humidity (RH) levels within the subfloor as part of any floorcovering installation. If subfloor relative humidity levels exceed 75% RH, a waterproof surface membrane will be required. The application of a suitable floor smoothing underlayment is also recommended to create a perfectly smooth base for floorcoverings.
Floorcoverings
Resilient floorcoverings are an obvious choice for damp and humid environments because they are not affected by moisture like other types of floorcoverings, such as wood, and can easily be cleaned.
Vinyl planks or tiles may be installed in humid environments, such as domestic bathrooms. However, the installation of vinyl sheet is recommended in wet rooms and other areas where floors will be subject to high levels of moisture, including standing water. In these situations, seams must be welded to ensure a watertight seal and prevent any ingress of water. For the same reason, areas where floorcoverings meet drains or capping and coving at walls should be sealed.
Due to the potential of water ingress, it is always advisable that floor coverings and vertical flooring accessories are installed using a suitably moisture resistant adhesive.
Adhesive selection
Epoxy or polyurethane adhesives have traditionally been the recommended option for making flooring installations impervious to water, inside and outdoors because of their high resistance to water, oil and grease.
The latest advancements in adhesives technology have enabled F. Ball to create a one-part, moisture-curing adhesive for internal and external heavy-duty applications, which is also solvent and isocyanate free: Styccobond F73 PLUS.
The adhesive has been specially developed to provide the high bond strength required to hold a wide range of floorcoverings in place in the most demanding environments, such as in areas subject to surface water, heavy loads and high foot traffic, including in transition areas and entranceways. Unlike reactive adhesives, the adhesive offers high initial grab, and fibres in the adhesive limit lateral movement of floorcoverings while contractors are working.
Styccobond F73 PLUS is also easier to apply and faster curing than traditional alternatives, requiring as little as 90 minutes to secure floorcoverings. Its fast setting properties allow welding of sheet floorcoverings to take place from as little as two hours.
Another solution
The arrival of hybrid adhesives, such as F. Ball’s Styccobond F49 Hybrid PS, provided another solution for installing resilient floorcoverings in damp and humid environments. As well as being resistant to water, Styccobond F49 offers the familiar characteristics of pressure sensitive adhesives, making it ideal for installing LVTs in these settings. It also develops the extremely high bond strength to hold floorcoverings in place in areas exposed to extreme temperature fluctuations (from -20°C to +60°C), which can cause tenting and gapping at the interface of adjacent tiles and planks and at the edges of floorcoverings.
Excellent resistance to plasticiser migration and high initial grab also makes Styccobond F49 an alternative to contact adhesives for installing vertical flooring accessories, including skirting, capping and coving, which are typically applied to vertical surfaces that may be subject to damp and humid conditions. This means that contractors can now use one adhesive to install both vinyl floorcoverings and accessories in these situations.
Compatibility check
Whatever type of adhesive is required, it’s recommended that contractors check the compatibility with chosen floorcoverings. For these purposes, F. Ball produces its industry-leading recommended adhesives guide (RAG®), which lists adhesives recommended for use with over 6,000 floorcoverings, produced by over 200 floorcovering manufacturers. It is available on the F. Ball website and as a free app, as well as a printed booklet. Contractors can also contact floorcovering manufacturers for advice.
Alternatively, F. Ball’s technical service department is on hand to answer any questions you might have about installing floorcoverings in damp and humid environments or floorcovering-adhesive compatibility, Monday to Friday, 8.30am–5.00pm.