Cost to replace subfloor in semi detached house

relax carry on

Trying to figure out might cost to replace the subfloor of the entire upstairs of our 3 bed semi-detached. Total sq foot of the house is about 900 sq feet. The upstairs would be 3 bedrooms, one bathroom and the landing.

Landing is carpeted. Bedrooms have laminate flooring and bathroom is tiled. The tiles and laminate are fine as they are probably only about down about 4 years.

All the upstairs floors are uneven and creak. Two parts of the landing near the stairs feels like some of the subfloor has broken or sunk in someway.

Bought the house two years ago and did notice that the floors were uneven but it's getting to me now. The estimated cost will determine if I can just ignore it.

Gumbo

Sub floor?
Are you talking about the floor joists?

JustJoe7240

kceire wrote: »

Sub floor?
Are you talking about the floor joists?

I think the OP is referring to the subfloor as the yanks use it, referring to the joists underneath their floor.I was thinking of the base floor when i read subfloor as i assume you were too.

relax carry on

Apologies for the incorrect terminology. Saw subfloor via Google and it seemed to fit.

I mean the flooring underneath the laminate/carpet/tiles which I assume is some sort of chipboard as the house is 30 years old.

Thanks.

jmBuildExt

he means the floor boards.... They are usally pine tongue&groove lengths. The main reason they become uneven is because someone has ripped part of it up at some stage to run acable/pipe etc.

Might be difficult to do completely, as the stud partitions will be sitting on top of them. That aside it still might not fix your problem fully.
It will definitely make the floor feel more even underfoot, but it could be the joists that are creaking...
I had downstairs joists and sub-floor replaced earlier in the year. I was doing large renovation that involved removing supporting wall between old kitchen and dining room. Anyway, the floor was uneven on each side so whole lot needed to be re-levelled as an extra on the job.

I remember the builder charged close to 2k to do it.. I thought at the time (and still do) he was ripping the piss a bit as the area was clear, no obstructions etc - and it was only about 25-30sqm. Ran new joists and sheeted over with plywood.

It was funny because he was really good value in other areas.

Gumbo

Remove all floor finishes (tiles, timber or carpets)
Remove any ply sheets of present but on older houses it with be T&G boards.
Assess them and see if they can be re-fixed to the joists below.

Should stop the creeking. Any further works would be substantial as you could be into wall removal, joist removal etc

relax carry on

kceire wrote: »

Remove all floor finishes (tiles, timber or carpets)
Remove any ply sheets of present but on older houses it with be T&G boards.
Assess them and see if they can be re-fixed to the joists below.

Should stop the creeking. Any further works would be substantial as you could be into wall removal, joist removal etc

Cheers that's what I'm after alright. Just trying to figure out how much that would cost assuming all that's needed to be done is take up everything as you say and either reuse or replace the plywood flooring and restore everything back. Hopefully it will fix reduce the creaking and the unevenness.

Lumen

I've just been quoted something like 14/sqm for laying engineered wood floor, 18mm T&G OSB3 is about 8/sqm so lets say 25/sqm for materials and labour including wastage.

For maybe 50sqm that would be approx 1250.

Plus screws, new skirting, skips, labour to strip existing flooring.

2k? Or 40/sqm.

Plus whatever new flooring you want, which is going to be at least the same again.

You might want to consider air tightness while you're at it.

relax carry on

Lumen wrote: »

I've just been quoted something like 14/sqm for laying engineered wood floor, 18mm T&G OSB3 is about 8/sqm so lets say 25/sqm for materials and labour including wastage.

For maybe 50sqm that would be approx 1250.

Plus screws, new skirting, skips, labour to strip existing flooring.

2k? Or 40/sqm.

Plus whatever new flooring you want, which is going to be at least the same again.

You might want to consider air tightness while you're at it.

Brilliant. That's exactly what I was looking for. So not off the wall expensive. The laminate flooring that's down while it's probably one of woodies cheaper offerings, is perfectly fine. It's the stuff underneath that's the problem.

Lumen

relax carry on wrote: »

Brilliant. That's exactly what I was looking for.

OK, bear in mind this is still a fairly wild stab in the dark. I'm not a tradesman.

relax carry on

Lumen wrote: »

OK, bear in mind this is still a fairly wild stab in the dark. I'm not a tradesman.

Cheers. Just hadn't a clue of what this might cost or even exactly what may need to be done. It's good to have even a rough idea.

jmBuildExt

Be careful here...
It wouldnt be beyond the realms of possability to have a stud wall running parallel to, and between, 2 joists - make sure whoever is doing it doesn't cut too close to the base of the stud wall on both sides. In that case the stud is currently being supported by your floorboards - and it in turn may have a load bearing down on it from above.
Cutting the floor boards inside the nearest joist in this case will make your stud wall want to go south.