Going the Extra Mile with Subfloor Preparation

At Altro, particularly in the technical services department, we’re often asked to arbitrate where there is a conflict of opinions between the flooring contractor and the architect, main contractor or end user.

A typical scenario is where the flooring contractor has done his level best to turn out a good job, often working in less than perfect conditions, or where during his efforts he has been trampled asunder by other trades.

Anyway, as usual it’s the bloke on his hands and knees who generally gets the worst of it. When the job is finished (on time and against all the odds) they suddenly put the lighting and heating on, remove the floor protection that was put down in semi-darkness the second the welding was finished, then immediately pull the job to pieces. That’s where we often come in to shed a bit of light, pun intended, and common sense on the situation.

Not that floorlayers are shrinking violets when it comes to standing their corner, but it’s a fact of life that assurances from a manufacturer that all is as well as can be expected under the circumstances carries a great deal of weight and is often all that’s needed to get payment released.

The most frequent issues we’re asked to comment on are subfloor preparation and the quality of the hot welding. Only this week I’ve attended meetings to address both subjects where complaints had been made.

Most welding, if reasonable to begin with, is easily put right – often just needing a bit more trimming with a newly sharpened spatula, or router tool if we’re talking about mitres. The real problems are when a smoothing screed has been applied and the trowel sweeps are clearly visible through the finished flooring. Big problem, and the hardest to defend or put right.

In the “olden days” when I first started out in the trade, all rubbing down of latex and even acrylic smoothing compound was done by hand, in my case with a 6” carbourundum stone. Oh the joy when I was an apprentice of being given the opportunity to rub down by hand several hundred metres of screed done the week before and set like granite, and the bliss after trapping my frozen little fingers for the umpteenth time as the block snagged and rolled on a winter’s morning with snow and frost on the ground and sub zero temperatures – and that was inside the building.

Sadly for the masochists out there that’s all changed now, or at least should have. These days, most smoothing compounds flow better than their predecessors and many flooring contractors have become mechanised, utilising old scrubbing machines fitted with sand paper or carborundum discs for the purpose, so at least the essential hard work of rubbing down can be done standing up.

It’s really worth going the extra mile with subfloor preparation, as once the flooring is down and people are demanding seasick tablets to walk across the floor there’s precious little that can be done, even if manufacturers of the flooring confirm that “the undulations in the smoothing compound that are visible through the finished flooring, though unsightly, are unlikely to cause a breakdown in the flooring system”. Often this does not serve to pacify the client whose expectations may be far higher than what has been achieved.

So, invest in a second hand scrubbing machine and a spiked roller, use them on every job where smoothing compound is laid, keep all the other trades out whilst you lay the floor and perfect results will be achieved every time. Okay, I know the ‘other trades’ bit is flooring fantasy, but at least you could give it a try.

This article first appeared in the June 2010 edition of the CFJ.