Fixing plywood sheet to concrete floor

[Paul Giverin]

I'm trying to lay a solid oak floor to a concrete base. Unfortunately there were Marley tiles on the existing floor (I'd forgotten they were there until I lifted the carpet). I've laboriously removed the 250 marley tiles with a heatgun and scrapper but the bituminous adhesive is impossible to remove completely.

The adhesive manufacturers say the adhesive won't work well over the bitumen layer so I have to cover it up. A layer of 6mm plywood has been suggested and it seems a good idea.

My question is what is the best way of securing the plywood to the concrete floor? I'm thinking that a nailgun would be the best method here. The area to be covered is 22 m2.

TIA,

[George]

Plug and screw.

Do check for any pipes running under/within the concrete base first?

[The Natural Philosopher]

Ah the old Hilti eh?

Id be inclined to use lots of gripfill type muckite (or tile cement?) as well..to gap fill what may be somewhat uneven.. or even whatever was originally used..usually a black bituminous sort of adhesive.

If you have access to a nail gun , know how to set it up, and the concrete is good and the nails don't fire right through the board..its probably the fastest.

Screws and plugs? yeah, but what a faff!

Or rip the floor up and re-screed. You have to balance the lesser of several evils.