Chipboard floor removal

[ajfinche]

This is in relation to my previous post //www.diynot.com/forums/building/rising-damp-or-not.291326/. I need to get a proper surveyor in to access my damp problem and he’ll want to access the sub floor. My flooring is chipboard and I cannot budge the majority of screws. I tried a screw extractor set which didn’t work and I drilled the heads off one of the smaller sheets and this still won’t budge. Due to some of musky smell transferring from the carpet to the floor I am planning on replacing the floor (and insulating at the same time) so with this in mind could someone give me some advice on the best way of removing the floor for the surveyor. It will still need it to function as a supporting floor until I replace it properly. My thinking was to circular saw around the edge over with the joists and use a special drill bit for cutting holes around the screws. My thinking is then it should just lift up and it will still be usable until I get a new floor.

 

[Burnerman]

Use an old (but sharp) 1" chisel to chop towards the screw head from a few angles - effectively to create a hollow where you should be able to get a claw hammer into. Even if the hammer doesn't pull the screws out, often the claw gets enough grip to help turn the screw. You could even use mole grips to turn the screw if enough of the head and shank are exposed.
John

 

[ajfinche]

Nice idea. I'll give that a try.

 

[big-all]

other method is to use a plug cutter
http://www.toolstation.com/shop/Titanium+Plug+Cutter+Set/p72650

 

[ajfinche]

Thanks. That's the sort of thing I was thinking of for the screws but didn't know the technical name.

 

[JohnD]

I use a circular saw with a TCT blade. It will cut through any screws you fail to avoid. Set depth to a fraction less than the 18mm board thickness (this is to reduce risk of damage to pipes and cables) and try to cut just to the side of the nail line and cut into convenient sized pieces you can pull out with a pry bar and hammer

chipboard is an awful material so I'd recommend 18mm WBP ply. You can use square-edge if you put noggins under all joints.

You can do the same with a trapdoor hatch for future access. Check subfloor ventilation and clean out all airbricks while it is open. Clear out all rubbish, dead mice and builders rubble especially wood scraps that can encourage rot and worm. You can add insulation as well.

Here's one I did earlier.

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