F BALL & CO has outlined a guide to wood floorcovering installations. It says: ‘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 cause wood to warp and attack adhesives, 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.’
The company continues: ‘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 & Co 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.’
F Ball & Co says it has two timesaving options for when a moisture management solution is required. ‘Stopgap F77 waterproof surface membrane is a two-part, epoxy resin system, which is applied in a single coat. It fully cures in as little as three hours and will isolate residual construction moisture or rising damp where relative humidity values are up to 98%.
‘For an even quicker way to create a barrier against residual construction moisture where RH values are up to 95%, there is Stopgap F78, a one-component system, which is applied in two coats, requiring 15–20 minutes curing time for the first and a further 30 minutes for the second.
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 says it recommends using a heavy-duty levelling compound, such as its Stopgap 300 HD, prior to the installation of wood floorcoverings because they’re 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, says the company.
The company continues: ‘One such flexible wood floor adhesive, F Ball’s Styccobond B95, provides good initial tack while also allowing for repositioning of floorcoverings during the initial stage of drying, an advantage when installing wood blocks.’
F Ball & Co 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 recommended adhesives guide (RAG), which lists adhesives recommended for use with more than 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.
F Ball & Co has provided what it describes as the ultimate luxury floor finish at One Hyde Park. F Ball’s Styccobond B95 flexible wood flooring adhesive has been used in the refurbishment of a multimillion-pound apartment at a luxury residential complex in Knightsbridge, London.
Floors of Distinction, based in Gerrards Cross, Buckinghamshire, was contracted by The MCT Group to install bespoke Jatoba engineered hardwood floorcoverings at the property.
In this case, moisture measurement tests were not necessary because the subfloor comprised a newly installed system of raised access anhydrite Knauf GIFAfloor panels.