Levelling a wooden floor

[John Forbes]

The level of my (1st floor) bedroom floor dips by approx 5" across its

19' width, and I want to it prior to installing wood or laminate.

One past post in this group points me towards screwing a second set of joists to the originals so that the tops of the new joists are all level with the highest point of the old joists. I like this idea because I really don't want to disturb the ceiling below. As far as I can tell the new joists wouldn't get "inserted" or tied in to into the wall brickwork in any way - they'd just butt up against it. Any views?

Having levelled the floor one way or another, can I then dispense with floorboards entirely and board out the room prior to laying the wood/ laminate? If so, what sort/ thickness of board? Ply/ chipboard/ OSB?

BTW, are there any specific building regs I need to worry about in all of this?

Thanks

John

[dg]

I would get some 'furring strips' cut (ie 5" down to nothing) and fix these to the top of the joists. This is less wieght than additional joists.

Normal 22mm T&G floring chipboard can then be fitted. Don't use plain ended boards - ie ply or OSB

I would also put some noggins between the higher new sections of the joists to prevent them twisting.

This is not structural work, so B/regs is not relevent. However, 5" is a big dip, so be sure that there is no underlying cause.

dg

[John Forbes]

[e-mail] (dg) wrote>

SW London terraced house on a hill, 110 years old, hence all of the houses in our street show some form of downhill list - from ridge lines to out of square lintels. Will have to patch some of the cracks before I sell !!

Anyway, thx for the reply. I'm not sure about a 5" high strip balanced on top of a 2" wide joist - any suggestions for securing this?

John

[N. Thornton]

sounds good. I'd want to either fit noggins to stop the new wood twisting over, or else screw the new chip sheet floor to every strip of new wood - the chip will stop the new wood moving sideways.

sure. 19mm flooring grade chip is standard.

It is, but it wont strength up the existing joists well. Since theyve sagged 5" in the middle I think its fair to conclude they could do with strengthening. It might be wise to inspect them for rot, severe woodworm, or just inadequate size once you get the floor up.

Regards, NT

[dg]

Either counter bore the hole so that a long screw will reach or fit some galv. splice plates to the sides, over the join, at the higher end of the furring strip. Or screw through the connection at an angle.

Fitting, say 8" noggins, at the higher end will also give 3 or 4" connection to the existing joists

The furring strip is not going anywhere, and the floor boarding will hold it in place - so its not as if you need lots of screws to hold it down at the higher end.

dg

[John Forbes]

As far as I can tell what's happened is that the whole building is listing down the hill, rather than the joists sagging in the middle, but I'll only know once I start to get the floorboards up!

Many thx for your input

John