floor squeeking please help...

[pam]

hi there

 

we are currently undergoing renovation work. And have had a subfloor laid which consist of 22mm chipboard fixed to timber CLS batons 400mm apart.

This sits on OSB and then a waterproof membrane which then sits on tiled concrete floor. The batons have been invariably packed with wooden/plaster packers 

 

The batons were not secured to the concrete floor underneath due to concerns of breaching the membrane.

 

the floor was making an awful screeching noise which was partially responded to hammer fixings through the board into the batons. although this has helped some of the noise it seems to have now moved somewhere else.

 

we are looking for helpful suggestions as to what we can do before we ulimately lift the chipboard and basically try and start again. which I fear is what is the inevitable....

 

[Onoff]

It's a common problem to have floors nailed down with angular ring nails like this:

 

 

Far better is to use SPAX flooring screws:

 

 

Ask me how I know! Our upstairs (ring nailed by hand) is 18mm T&G chipboard on 400mm centres and it initially had terrible problems. The SPAX have made it better but it's still not perfect. All the noggins appear hand nailed so I think they might be part of the problem.

[pam]

hi there thanks for your quick response. we definitely used spax flooring screws as my husband bought them. he wanted Timco collated screws but couldn't source them and therefore went for the spax 4.5x60mm screws. we don't have any noggins in the main part of the floor which along with the joists not being secured to the concrete floor is what's causing it to squeak... I think...

[Onoff]

I did a similar floor downstairs:

 

- Original concrete subfloor

- 2 layers of waxed building paper

- 4x2 CLS @ 400mm ctrs (in effect a glued & screwed stud wall laid on its side)

- 100x100 ply packers  - thickness to suit. These slipped under the floor joists with a big slug of D4 glue at each point.

-22mm T&G affixed with SPAX

 

It's the best floor in the house. Not a peep of noise and rock solid. 

 

Might sound a mad idea but I wonder if you could pour some sort of self levelling compound in through some discreet holes to flow under all the gaps?

 

Maybe via a solid board cutter:

 

 

[pam]

thanks so much for your reply. its definitely a good shout and I will discuss with builder and architect. here is a photo of our floor before the chipboard went down.

I have kind of resigned myself to lifting the floor up or maybe a few boards and then trying to secure the joists to the concrete floor. can I ask how you secured your CLS batons to the concrete floor ? did you use hammer fixings with washers and what size CLS timbers did you use?

[MAB]

My chipboard floor in my extension only started squeaking after all the carpets had been fitted!.......as I fitted the chipboard floor I just lived with it and don't notice it anymore, plus the rest of the house is 1930's suspended timber floorboards and stairs which have always had various squeaks and creaks!

[Onoff]

My CLS is not secured to the concrete floor in any way whatsoever. Not got many photos of back then but a few. We had a low boot room / coal store  that was lower than the rest of the house. (Previous owner used to breed rabbits in there). I simply put a DPC down, 2 layers of wax building paper (no idea why) then made up a glued and screwed "stud wall" which I then laid down flat. The "frame" has a gap underneath. You can just see 2 of the 100x100 ply packs. I laid the frame down and figured how much it had to come up to meet the adjacent floor. Then just slipped in ply packs to suit the gap at that point be it 6, 9, 12, 18, 24mm etc. I lifted the frame off the packs and put a big squrt of pva between ply and underside of the CLS then left to dry. Rock solid is an understatement, no squeaks whatsoever! Widened the doorway, studded the walls etc:

 

 

I've only got 100mm of roll insulation between joists. There's also a deliberate gap all round the floor frame. I had some mad idea it would be good for airflow/to stop damp! ?

 

 

NB: This was before I discovered the forum or I'd have done it all different with UFH and masses of insulation under the floor that I'd have had to dig deeper. Hindsight eh!

Edited June 6, 2020 by Onoff

[pam]

that's great work onoff. unfortunately I don't know how many packers were used and at what spaces. what size of CLS did you use? I see you also laid them on their side

 

however, we have just had confirmation from the architect that a self levelling screed should have been used. it was in the architects plans.

so we now have to lift entire floor including batons and OSB. the OSB was used to secure the batons to it and also used as a packer. however, I think it has compounded the problem because it is moving on its own. because we have tiles underneath with some areas having big gaps that hasn't helped with securing the CLS and thus causing it to flex over the large unsuported areas.

 

I will keep you updated once floor is up and once I have managed to find a company/person who can screed the floor. 

any idea who I should be looking for? is there a specific tradesmen/professional who does this type of work?

 

Edited June 6, 2020 by pam

[Onoff]

44 minutes ago, pam said:

what size of CLS did you use?

 

45x95 so "4x2".

[JFDIY]

I wouldn't try and screed it level then repeat the same build up, you will still get voids and take a lot of time to get there.

 

If its coming out anyway I'd  remove the top layer, the drill the OSB to the side of the CLS battons with a big hole, then inject underneath them to fill the gap.

 

You can get specialist 'flowing' grouts for this, but my only previous was filling deliberate 40mm void under large steel structures where money wasn't a consideration and we poured from one side with a big hopper to get full fill over 5m X 7m

 

Anyway in this case you don't want to pump so much in it all starts to float on it. Might get away with self levelling or similar poured in, tricky part will be not deflecting it locally (by standing on a soft spot) while your pouring in the jollop.

 

Flowing grout would be less susceptible to shrinkage during curing than self levelling compound

[pam]

Thanks for your suggestion but I can’t imagine that will work. The OSB has added another level of complexity to the construct and is so unpredictable. Therefore I think removing it will

allow us to see how the CLS timbers lie on the tiled floor. We can then see how off it is before laying the self levelling screed.this is the way it should have been done from the start. Unfortunately the plans weren’t read properly.

[Onoff]

12 minutes ago, pam said:

Thanks for your suggestion but I can’t imagine that will work. The OSB has added another level of complexity to the construct and is so unpredictable. Therefore I think removing it will

allow us to see how the CLS timbers lie on the tiled floor. We can then see how off it is before laying the self levelling screed.this is the way it should have been done from the start. Unfortunately the plans weren’t read properly.

 

I can't see the need tbh for the underlying OSB over the whole area.

 

I'd set up a laser and locally pack (like I did) to level it. You could stick the packs to the tiles then the CLS to the pack. 

 

Is there any insulation under that original, tiled floor? Guessing not. Filling between the CLS with insulation would be a good idea. It'd cut down on any drumming noise too as you walk across it. 

 

 

 

 

 

 

[Nickfromwales]

First question, why is the timber floor necessary?

If the floor was tiled and they were glazed ceramic or porcelain then they would never have breached damp upwards, and if using a DPC then it would be bombproof. Hammer in fixings with an all plastic contact surface, installed avoiding grout lines ( which would be the only weak points as far as damp bridging is concerned ) would have caused no issue whatsoever. 
So, why the timber floor ?

[pam]

hi there thanks so much for your replies. to answer your questions -

 

1. no insulation under the tiled floor. and not sure whether there was a DPM in the original concrete slab.

2. timber floor was the spec by the architect. we needed to raise the floor up 130mm. therefore it was decided to lay a DPM, then batons, the chipboard. our plan thereafter was to put down engineered floor.

 

Update from previous post - joiner holds his hands up at OSb was not a good idea. It also turns out that no screed was used at all in the areas where the tiles were missing. Just packed up with OSB. The floor has no been completely removed. We had a screeding company come an put a laser on the floor. It is only out at some places by 5-10mm but obviously more where the tiles are missing.

 

so I have 2 options after bring the floor level to the tiles by filling the small areas where there is no tile with sand and then

 

1. lay insulation boards (total 80mm). enclosing pipes within the boards and then DPM and then pour screed of 50mm and level floor. then final floor

 

2. level floor with 25mm screed directly over the tiles and then lay DPM and then batons packed with insulation and run pipes through this and then chipboard.

 

not really sure which option to take tbh. option 1 sounds tempting but I am concerned about laying pipes under concrete screed within insulation boards. we also would need to encase gas pipe in this and this would be protected in a channel. 

 

option 2 would give us reassurance that pipes were available under the chipboard but my concern would be the return of the squeaking as the batons would not be fixed. although I think we would fixed them this time through the DPM accepting the risk of damp.

 

out of interest when I lifted the DPM there was moisture between this and the tiled floor. now we have had all the pipes taken up and therefore water could have got through the DPM but not sure about this. I guess one option is to get floor moisture tested?

 

thanks again for your comments. look forward to hearing from you.