Options for laying over uneven flooring

hanvyj · 13 Oct 2019

I'm planning on laying on solid wood parquet flooring in our hall.

The current floorboards are not in great condition so, after doing some reading, I decided to lay 12mm ply to remove any irregularities etc and glue down solid wood.

Now I've come to lay it I'm concerned about the larger scale unevenness of the floor. The plywood "rocks", and although I could screw it down - would the curve cause problems for the floor on top?

How much "gradual" curve can glued down flooring take?

It's an old house, so nothing is square or level. But is this too much?

The joists underneath look to have had some work:

bobasd · 13 Oct 2019

are the joists level left to right in the pics?
can you crawl under the floor and examine the ends of the joists crossing the hall and in the middle room?
is there a brick knee wall between two of the joists at the top of the opening in your pics or is that showing joist edges?

hanvyj · 13 Oct 2019

They look to be reasonably level with each other the on either side of the "peak" Doesn't seem to just be one joist that's high.

Looks like whoever replaced the joists did a terrible job...

It's not deep enough to get access.

I think they put 3 joists there because it was always a peak and they wanted extra support as all the floorboards all had a join along that point...

hanvyj · 13 Oct 2019

Maybe it is just the one that's high actually... Hard to tell!

bobasd · 13 Oct 2019

seeing as you've lifted a few boards then why not lift the other's and be able to examine the cluster of 3 x joists to see if they are rotten - the noggin/support is rotten and should be replaced with sound wood.

you could remove nails from the high joist, and plane or chisel it more or less level with the other joists.

is there any movement in the floor or squeaking?

hanvyj · 13 Oct 2019

Yeah, next weekend I'm going to pull the rest of the board up and hopefully see the ends of the joist, and try work out if I can plane it.

Floor seemed sound - only one board squeeks in a different location where some board had been replaced. There's no noticeable movement in this location, but the joists span a very short distance.

The floorboards themselves are very poor (always split when I try lift them, and generally uneven and weak. There was once a piano in the hall and it managed to punch through a few holes in boards, never had any problems with joists though!)

That was the reason I planned on the 12mm ply over the top!

Tigercubrider · 13 Oct 2019

How big is the hall?
If you are lifting lots of boards and doing adjustments it might be quicker to lift the lot, level the joists if necessary and add 18mm ply in place of boards

hanvyj · 19 Oct 2019

No idea if this is good or bad:

Looks like the big that's raised up is only one side of the joist

dazlight · 19 Oct 2019

screw loose floorboards down.
I’d be going 9 or 12mm sp101 plywood
Then work out levels and make with plywood.
then prime and use a fibre smoothing compound to get levels.

hanvyj · 23 Oct 2019

We replaced one really dodgy joist and an area of floorboards.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Options for laying over uneven flooring

Similar threads