The reason to would be differential thermal expansion PVC is between 54 and 110 x 10^-6 mm/'C (assume 80) Concrete (sub floor) is 13 to 14mm x 10^-6/-C (assume 13) So assuming room when Rob laid it was 15'C In Summer Worse case - floor would reach 35'C (+20'C) In Winter - reach -5'C (-20'C) So for summer - if we assume nominal rate of 80 and 13 for the substrates the difference is 67 (differential expansion rate) so Rob's garage - assume is 6M long - 6000mm and 4M wide - 4000mm 6000 x 0.000067 x 20 ('C) = 8.04mm Growth So the PVC tiles would grow 8.04mm more than the sub floor over length 4000 x 0.000067 x 20 ('C) = 5.36mm Growth So the PVC tiles would grow 5.36mm more than the sub floor over width In winter - it would shrink by the same measurements.... So without knowing the actual shrinkage rate of the tile - these are best guesses... as some materials grow more in one direction than another due to material constituents and manufacturing processes.. So Rob should have allowed 4mm gap per side - and the skirting should be at least 8mm wide over top to cover in cold.. But this is ALL theory... in practice not sure you would see quite this much temperature variation in the floor.
In hot weather it can expand enough to buckle the flooring. 2mm on each walled side of the garage per metre of tile should be enough. Run a bead of matching flexible silicone sealant around to keep it neat and stop it being a dust trap but still allow the expansion and contraction.
just caught up with your photos. If I was in your garage, I don't think I would know where to look. Its great.
I have fitted many wooden floating floors over the years and it's paramount to leave a expansion gap for a change in temperature
The temperature in my garage doesn't change much, a bit like a wine cellar. We have some of the world's natural worriers as members on here.
Lots of interesting stuff so just thought I’d update on this stuff, https://www.costco.co.uk/Tyres-Auto...r-75-x-17ft-23-x-52M-Floor-Protector/p/112281 bought from Costco and been down about 2 years (ish). Sad to say IME, for high traffic use, I tend to park my car in the garage rather than outside my house so it’s in and out quite a lot, it’s not best value. The up side is it’s dead easy to lay and looks really good for the first few days. The down sides are the ‘plastic’ scorches at the temperature the tyres are at after a 20 mile drive; if you put the car away wet, the water that drains off the car lays in puddles which if you don’t sweep it away, promotes rust on any unpainted/uncoated metal surface; the flooring is labour intensive to keep clean and it’s looking very tatty. Biggest lesson learned for me when I replace this stuff is to have a drain channel the length of the garage. Andy
You also buy from the same place as Rob? Only joint seems less noticeable - but yours looks like a flat finish tile too... Thanks GOOD JOB!!!! (Sorry for the Americanism..)
Yes I got Duramat the same as Rob but I went for the smooth finish because it's a woodwork shop and I wanted it easy to clean. I'm really impressed. They are easy to lay and look great.