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Commercial Flooring News

Details Of The Job

EARLIER this year I was asked to visit the refurbishment of a public building in the West Midlands. The contractor wanted me to assess whether there was moisture in the subfloor, and then to recommend the best plan of action, including the relevant products to use.

The area had been stripped of the floor finishing, and an indicative test showed that there were pockets of moisture present. This was confirmed by an independent CFA expert, who also discovered a crack in

the subfloor.

However, it wasn’t clear if there was a suitable damp proof membrane installed; so it was difficult to say exactly what was causing these problems.

Staff on site believed that there was indeed a suitable DPM present, because during groundwork to dig a channel for a waste pipe through the subfloor they had found a layer of polythene. Yet our inspections suggested that if one was fitted, it needed some work to make sure no moisture was passing through.

Obviously, the next course of action depended on whether there was a DPM or not. The requested specification was supplied with details for what to do in the instance of a suitable DPM being present, and where not.

One option was to fit a membrane, primer and latex based smoothing compound; the other was to use just the primer and smoothing compound.

Taking his lead from the staff on site, the flooring contractor had proceeded work to our second option, which assumed the DPM did not need installing or repairing. As with so many projects of this sort, at first all seemed fine. But sure enough a few weeks later there were signs that the finish was delaminating and starting to create a health and safety hazard, especially as the area had a high level of foot traffic.

Visiting the site once again, it was immediately clear that the problem was likely being caused by the same moisture patches I’d identified months previously. As you might expect, discussions from here were over who was at fault; the flooring contractor had his payment withheld until someone agreed to pay to repair the problem.
To me, it seems the problem could have been avoided on all sides if there had been a thorough check of the DPM. A suitable specification had been supplied to accommodate different scenarios, but somewhere along the line the decision had been made to proceed without checking properly, with some people on site adamant that there was no issue with the DPM.

It’s likely that the situation arose from pressure to finish the job on time and on budget. Clearly, this isn’t the fault of the flooring contractor if he is told to proceed to a given specification stated as being correct. However, especially with the continuing poor state of the economy there seems to be more pressure of this sort, and a greater temptation to cut corners in the name of efficiency.

So, my point is that it pays to keep an eye on the details of a job,check that everything is as it should be when taking information from others on site. It could help to avoid a tricky situation later down the line.

John Alcock is technical specifications manager at Bostik
T: 01785 272727

This article has been reproduced from the Contract Flooring Journal website. You can find them at