WHEN The Kingsmead Academy in Taunton decided to construct a new main teaching block, the existing building had been standing for more than half a century – since the school first opened in 1953.

The building was in a state of disrepair and needed replacing with a contemporary block better suited to the demands of modern teaching. The school appointed main contractor Bouygues UK to build the £10m three-storey teaching block with a one-storey main hall, and Bouygues turned to CW Jones Carpet & Flooring to install the floorcoverings.

CW Jones then contacted trusted supplier Bostik for its subfloor preparation products and flooring adhesives, as well as its expert technical support.

Test results
Once the new building had been constructed, Bostik’s team of technical experts visited the site to inspect the subfloors and make their recommendations on how best to apply the floorcoverings.
When they tested for moisture, the team found most of the subfloors were wet, exhibiting an average of 86% relative humidity (RH).

This is well in excess of the 75% RH threshold that British Standards defines as a wet subfloor, and meant it would be necessary to apply a surface damp-proof membrane (DPM) before the floorcoverings could be laid.


Further inspection revealed that most areas of the concrete subfloors were rough-textured and pitted, and would therefore require pre-smoothing before the DPM was applied, since applying DPM to a rough subfloor compromises its effectiveness and can result in product wastage.

On the other hand, some areas were soft and exhibited surface laitance. These would need to be removed to return the subfloor to a strong, sound base.

Getting to work
Following Bostik’s recommendations, CW Jones pre-smoothed the rough areas of the subfloor to create a smoother surface on which to apply the DPM.

Says Bostik: ‘This was done by applying GRIP A526 UNIVERSAL PRIMER – Bostik’s acrylic dispersion primer that offers excellent coverage rates and dries within one hour – followed by the company’s SL C540 FLOW smoothing compound. The high-flow, easy-trowelling SL C540 FLOW has a moisture-tolerant formula that makes it ideal for smoothing rough-textured subfloors prior to the application of the DPM.

‘Once the smoothing compound had dried, CW Jones was able to apply Bostik HYTEC E570 ONE COAT, a two-part, solvent-free, epoxy surface DPM that contains the exact quantities of resin and hardener ready for mixing together. With the ability to provide protection up to a maximum hygrometer reading of 97%RH with a single coat, this successfully suppressed the excess moisture.
After further applications of GRIP A526 UNIVERSAL PRIMER and SL C540 FLOW, it was then time to lay the vinyl and safety flooring. CW Jones did this using STIX A300 MULTI FLOOR, Bostik’s multi-functional acrylic adhesive that has a high initial tack combined with a long open time and exceptional handling characteristics.’

Invaluable input
The company continues: ‘Aided by Bostik’s expert advice and high-quality products, the floorcoverings were laid on time and to specification. This enabled the main contractor to hand over the building to a satisfied school, which is now using it to teach most of its lessons.’

‘As always, it was great working with Bostik on this project,’ comments Samuel Jones at CW Jones Carpet & Flooring.

‘Bostik completed a site survey and provided us with a specification to use the full Bostik system, from DPM to smoothing compound and adhesive. Throughout the project, Bostik helped us by carrying out moisture tests monitoring and updating the specification when needed.’
www.bostik-profloor.co.uk