Hi, I'm looking to fit quickstep alpha bloom click LVT in my living room and I'm looking for some advice on preparing the floor. It's an older property with the original timber floorboards. I've checked the level with a 4ft spirit level and there is a few mm deviation over this length, but nothing too bad. I'm planning to use flooring grade plywood over the floorboards, and I have a couple of questions about this - - is 6mm ply suitable, or does it need to be 9mm. It will be screwed down in either case. - do I butt the boards against each other or should I leave a small expansion gap - If I leave a gap, does the gap and any screw heads that have been countersunk need to be filled. If so, what should I use for this. Thanks.
9mm would be better as more strength and will be flatter. Butt them up. You won’t need to fill the screw heads
