When nature gets involved in flooring
John advises flooring contractors on the appropriate steps to take when installing nature’s own brand of flooring.
WHEN installing wood floorcoverings, contractors should follow the same principles of floorcovering installation while bearing in mind a few unique considerations, chief of which should be wood’s natural susceptibility to moisture. If unmanaged, excess subfloor moisture will attack adhesives and cause wood to warp, potentially resulting in the floorcoverings cupping or buckling, and, ultimately, complete floor failure.
Wood can also expand and contract significantly as a result of changes in atmospheric conditions, including temperature and humidity, exerting strain on adhesives and the surface to which floorcoverings are bonded. Engineered wood is less prone to this but it will still be affected.
For these reasons, installing wood floorcoverings is a frequent topic of questions to F. Ball’s technical service department. Adhering to the following steps will ensure a long lasting, professional flooring finish throughout the lifetime of the floorcovering.
Having ensured the subfloor is suitably sound, smooth and free of any contaminant, including any old adhesive residues, it’s essential to determine if it’s dry enough to receive floorcoverings by undertaking a moisture test. F Ball recommends this as a routine procedure as part of any flooring installation. To comply with British Standards, subfloor Relative Humidity (RH) levels should be measured using a calibrated digital hygrometer.
Normally, a waterproof surface membrane will be required to suppress excess subfloor moisture when subfloor RH levels are above 75%. However, the maximum permitted figure is 65% where wood floorcoverings will be installed because of the sensitivity of this type of floorcovering to moisture. Waterproof surface membranes create a barrier between floorcoverings and subfloor, protecting the floorcovering from the adverse effects of excess subfloor moisture. The best products protect against RH levels of up to 98%.
Once a moisture management solution is in place, contractors can proceed to apply a levelling compound to ensure a perfectly smooth base for the receipt of floorcoverings, remembering to prime the subfloor beforehand. F. Ball recommends using a heavy-duty levelling compound, such as Stopgap 300 HD, prior to the installation of wood floorcoverings because they are better able to withstand the added strain exerted by the natural movement of the wood.
Choosing the right adhesive
Finally, contractors must select a specialist wood adhesive to install wood blocks or planks. Utilising the latest technology, flexible wood floor adhesives provide an elastic but strong bond, which will accommodate natural movement of wood flooring over its lifetime, ensuring a long lasting, visually attractive floor finish.
F Ball’s Styccobond B95 is a high performance, flexible wood flooring adhesive that provides good initial tack whilst also allowing for repositioning of floorcoverings during the initial stage of drying, an advantage when installing wood blocks. F Ball also recommends Stycco Flex, its rapid-curing flexible cartridge adhesive, as an alternative for securing header rows.
Its rapid strength build-up aids installations where subsequent rows are butted up to the head row using a mallet and a tapping block. Stycco Flex can also be used to install skirting boards and trims.
To ensure the correct choice of adhesive for the floorcovering, F Ball recommends checking the compatibility using its industry-leading recommended adhesives guide (RAG), which lists adhesives recommended for use with over 6,000 floorcoverings, produced by over 200 flooring manufacturers. The RAG is available on the F Ball website, downloadable as a free app, as well as a printed booklet. Alternatively, see floorcovering manufacturer’s instructions for advice.
F Ball’s technical service department is also on hand Monday to Friday, 8.30am–5.00pm, to answer any questions you might have about installing wood floorcoverings or floorcovering-adhesive compatibility.