Hardboard on floor buckled... what to do?

16 Oct 2009
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United Kingdom
Yesterday I had a carpet put into my bedroom, and asked for the floor to be covered with hardboard first to prevent 'filtration marks' on the carpet. I would have done the hardboarding myself but I knew the 'pros' would be quicker and having just moved into my flat I wanted to get the job done so I could unpack. Anyway, overnight the hardboard sheets have clearly all expanded and buckled so it feels like walking on a (loud) bouncy castle. I didn't see the hardboard being conditioned before being put down (it certainly wasn't left in the room for 24 hours as I have seen recommended), but I assumed it might be some kind of pre-conditioned hardboard.

The question is, what can I do about it? The underlay and carpet have alreay been fitted over the hardboard (I don't know if anything has been stuck down). I am thinking I will have to lift the carpet where possible (i.e. where my newly installed bed isn't), pry up the hardboard, trim the edges with knife and nail it back down. Do you think this will work? Any other suggestions? Any advice much appreciated!
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Simple answer, get the "pro's" back to do it properly. Hardboard must be damped on the back and left in the room for 24 hours, They should know that.
i thought they used pre stressed hardboard now?
but i agree if your not happy then call them back to sort it.
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Just spoke to a carpet fitter I know and he said the hardboard should be dampened down on the rough side then left to 'acclimatise' in the room it is going to be laid in for at least 24 hours but preferably a little longer.
When laying it start on the longest straight wall and fasten the first piece 6-10 mm away from the skirting using 'lost-head' pins, not tacks or nails. The heads have a diamond shape to them which grip into the hardboard. Leave a 5mm gap between boards, stagger the joints and most importantly, pin them at 9" intervals in both directions, (i.e. start about 10mm from the edge of the wall side and nail along the wall length at 9" intervals then start a second row 9" in and repeat the process but on the second row move the first pin in to the right about 25mm so the pins are staggered also, repeat for the third row but go back to the edge of the board in line with the first row. This guaranttees that the boards will not warp and buckle.
BTW, pro's use a gun for these pins not a hammer so they can do it very quickly. Get them back and tell them to do it properly.

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