Don’t Rely On Datasheets In Poor Conditions
Martin Cummins won’t lay in his conservatory this winter Part 3
LAST month I looked at problems when using smoothing compounds and adhesives in cold, stagnant buildings where there is little movement of air and resulting moisture.
With regard to floorcoverings the main culprit with vinyl, linoleum and rubber flooring is cold temperatures. The floorcoverings must be stored and fitted at a reasonable temperature to enable cutting, shaping and bonding.
Typical expected temperature is a minimum 18degC. A cold resilient flooring has a great deal of tension and will curl up very readily as soon as it is cut. Manufacturers quote minimum temperatures to lay for a reason, the flooring needs to be malleable enough to flatten and bond or, where required, to shape for coving etc.
Areas being installed in may have added heat to achieve this, but if this heating is removed soon after fitting then the flooring can begin to tension up. The result can be a great deal of strain on the adhesives which don’t build up bond strength under the low temperatures.
Although carpets generally have much less of an issue with temperature, there is still a need to install them under reasonable conditions. Coldness is still a concern as it makes all materials more rigid. However with carpets moist air is also a major culprit in the long term rather than just in the installation phase.
Many carpets ‘relax’ somewhat as they get damp, so may be relatively easy to cut and not have the curl problem associated with vinyl. Often the adhesives used have high grab properties capable of performing under less favourable conditions, so a carpet installation may be achieved under poor site conditions.
However, as the building comes into service and the carpets begin to lose this moisture they can shrink and begin to curl, causing gapping and sometimes lifting at joints. Stitching and seaming are not necessarily carried out these days, so each individual run of carpet is isolated from its neighbour enabling it to move in isolation, hence shrinkage gaps occurring.
Timber flooring is probably the one product where contractors understand the need for reasonable conditions as we all seem to appreciate that damp timber will dry out and warp/curl/split.
My concern is that the move towards engineered wood flooring will give a false sense of security as they are often quoted as stable
flooring materials, not prone to the shrinkage, splitting, cupping etc of solid timber. Although this may be true, it does not mean that the flooring can be laid at 10degC on a damp building site with no windows. Remember to treat the timber with the respect it deserves and give it the best chance of performing.
It is plain that my conservatory this winter is a no go area for new flooring. I understand that flooring works must continue on sites throughout the winter but tell the main contractor you need conditions that enable products to perform, including:
• Reasonable temperatures; I Low air humidity; and
• Good airflow to take moist air away. Do not expect products to perform as per datasheet information if the conditions are poor. Allow extra time for curing and drying. On large projects get a warm area on site where products can be stored correctly, including adhesives, primers, DPMs and not just the floorcoverings.
Martin Cummins, Ultra Floor technical sales manager
T: 01827 871871
This article has been reproduced from the Contract Flooring Journal website. You can find them at www.contractflooringjournal.co.uk.