floating chipboard floor issues

[TSCfree]

Overthinking this surely. rip up chipboard and lay laminate over the top of the celotex. It's the chipboards movement that's causing the squeaking. We layed fibre board down on top of a concrete floor many years ago without issue.

[anonymous-user]

Chipboard directly over insulation can creak due to movement between the chipboard and insulation. It can be really bad over EPS, but can also happen over foil faced insulation.

The 'best' way to fix it is to lift the chipboard and replace it but placing a layer of polythene between the chipboard and the insulation. This acts a slip membrane and allows movement of the two without the squeaking.

Equally it could be noise from the board joints due to poor gluing or wetting causing failure of the glue, but experience shows that it can happen anyway due to the afore mentioned movement.

No other way to deal with it though from what I have seen other than to take up and install new with decent glue and a slip membrane.

[Toyoda]

I feel your pain. My 1980's build has the same abomination downstairs. Inevitably over time the higher trafficed areas can start to sag a bit. Plus there's the moisture in the air which wont help. We're talking cheap chipboard sheets here, they're not gonna last a lifetime. Mine is a white polystyrene looking insulation with chipboard t&g sheets over it. If you ever need to lift it e.g. for adding/moving water or gas pipes then you're fooked. Like you say, you cant lift it like floorboards so you have to cut into it, but once you cut into it then it's lost its integrity, which comes from a good glued t&g join and good fit round the room perimeter. I suppose one way to sort it would be to install battens on top of the concrete and then fix the chipboard to that, but it's going to take a lot of effort.Even more so would be to rip it all up and lay a proper concrete floor.

No wonder when I moved in the previous owner had carpet throughout and lino in the kitchen! You'd never fit laminate floor quite simply because the floor is far from level. How can it be?! It's polystyrene and chipboard sheets that have been walked on for 30 years! Modern houses, who'd have them. My next place will be strictly concrete downstairs.

hab1966 said:

Any advice/suggestions gratefully received!

Move to a house built properly with a concrete floor.

Edited by Toyoda on Friday 17th February 22:47

[roofer]

Skodasupercar said:

Chipboard directly over insulation can creak due to movement between the chipboard and insulation. It can be really bad over EPS, but can also happen over foil faced insulation.

The 'best' way to fix it is to lift the chipboard and replace it but placing a layer of polythene between the chipboard and the insulation. This acts a slip membrane and allows movement of the two without the squeaking.

Equally it could be noise from the board joints due to poor gluing or wetting causing failure of the glue, but experience shows that it can happen anyway due to the afore mentioned movement.

No other way to deal with it though from what I have seen other than to take up and install new with decent glue and a slip membrane.

This is the most accurate comment regarding your issue.

[kurt535]

take up floor and pipe in a concrete floor. anything else you do won't work stopping movement.

[Gtom]

Just take the chipboard up and relay new stuff with pu glue.

Depending on the thickness of the insulation board (not thermal blocks) you could cut out enough to sink some 3x2 cls (38x63) into it and screw the boards to that.

[strath44]

kurt535 said:

take up floor and pipe in a concrete floor. anything else you do won't work stopping movement.

I can't see how that is possibly a good idea considering what's already there and age of the house

[hab1966]

Wow.

Thanks for all the responses. I'm happy doing the work to the rooms but i'm not sure how to deal with the area around the stairs in the hall, so I've arranged for a couple of tradesmen to come around and quote for the work.

[strath44]

I know this is common place but what dreadful design, as someone mentions above over time apart from the squeaking you will see sagging in high traffic areas as well (irrelevant of the compressive strength of the insulation which is not infinite!)

The suggestion of getting some joists in there and probably some dwangs / noggins to strengthen everything then insulate in between the joists and put new chipboard on top glued and screwed then you'll be in a much better place

Does the chipboard go under the walls or stop under the skirting?

[paulrockliffe]

strath44 said:

I know this is common place but what dreadful design, as someone mentions above over time apart from the squeaking you will see sagging in high traffic areas as well (irrelevant of the compressive strength of the insulation which is not infinite!)

I would agree with that, but my parents have the same setup and 26 years later there's been no movement at all. I don't really understand how.

The load is about as well spread out as it's possible to get though, in theory if there was zero deflection in the chipboard the load would be distributed perfectly evenly across the insulation, it's only the local deflection that causes point loading. Maybe that's it.

[hab1966]

strath44 said:

Does the chipboard go under the walls or stop under the skirting?

Until last night i would have said no as i thought all the downstairs rooms were solid construction. However, the tradesman who came last night seemed to think that one of the walls might be of frame construction so built onto the floor.

I guess we will only find out when we start the work.

[strath44]

are you going to put joists or supports in touching the floor?

just because of the chipboard chat some people may be interested in these special spax chipboard screws (£14 at screwfix so not that cheap) I've used a lot recently and very happy with them.

http://www.jewson.co.uk/tools-fixings-ironmongery/...

[Toyoda]

paulrockliffe said:

I would agree with that, but my parents have the same setup and 26 years later there's been no movement at all. I don't really understand how.

The load is about as well spread out as it's possible to get though, in theory if there was zero deflection in the chipboard the load would be distributed perfectly evenly across the insulation, it's only the local deflection that causes point loading. Maybe that's it.

Maybe they tiptoe everywhere?! Maybe there's never any kids running around or anyone over 9 stone visiting?! It stands to reason that polystyrene and chipboard simply will not stand up to years of being walked over without deflecting somewhat, even with perfect load distribution. You've got the weight of heavy pieces of furniture but more importantly the walking back and forth, combined with the fact that chipboard over time simply isn't a solid structure, we all know that wood (or wood based products) warp, shrink, bend and in this case, deflect over time.

[kurt535]

strath44 said:

kurt535 said:

take up floor and pipe in a concrete floor. anything else you do won't work stopping movement.

I can't see how that is possibly a good idea considering what's already there and age of the house

hi Strath,

Just done the very same thing on two houses with same issue. Was only way to stabilise the floor and ensure it met thermal requirements

[strath44]

Even when starting with a concrete base already?

[Andehh]

What about removing chipboard and laying a self levelling flesible screed over the top - 30-40mm thick, then using that as the flooring?

You could do a lot of that yourself, and would give you a more robust floor then the chipboard.

[Toyoda]

Thanks for the info there. I'm not the OP but you'll have seen my post above as my ground floor is of the same construction.

Is it a method still used in new builds today? It does seem a really flawed method, I mean, yours is a 90s build and you're having to replace it already at a decent cost I imagine. Why did yours need full replacement? Were you not tempted to replace it with a different flooring type?

[anonymous-user]

Toyoda said:

Thanks for the info there. I'm not the OP but you'll have seen my post above as my ground floor is of the same construction.

Is it a method still used in new builds today? It does seem a really flawed method, I mean, yours is a 90s build and you're having to replace it already at a decent cost I imagine. Why did yours need full replacement? Were you not tempted to replace it with a different flooring type?

Still used today - it is fast and dry which has big benefits from a construction point of view. If you have a flat base and use a slip membrane then it can work well. Used extensively in the ground floor rooms of new-build chain hotels. It can last perfectly fine and doesn't squeak if fitted well and has that all important slip membrane.

[anonymous-user]

Because the chipboard and insulation are integral to one another. I must confess I have never come across chipboard with EPS bonded to it - normally these types of floors are formed using separate layers of insulation and chipboard and so a slip layer can be fitted as in very important. The OP had foil-faced foam and chipboard as separate items.

[Toyoda]

DaveWilks said:

Its worth mentioning that white polystyrene insulation floor panels could be XPS which has an inferior compressive strength to EPS polystyrene. This might be why the other poster's floor is sagging in high traffic areas. Or the build was poor to begin with because the subfloor wasn't level and flat.
The floor insulation that was included with the original build of my property is blue 50mm thick styrofoam EPS. You can still buy this. Pack of 8 boards 50mm x 2500mm x 600mm, for about £125.00 including VAT & delivery. I bought one pack to complete my bedroom. 50mm thick EPS is recommended for residential buildings. And if replacing an exisitng floor you might have no choice but to use the same thickness materials as the original build because the internal walls and door frames will have been constructed to the original floor level - the floor was built first and then the walls and door openings.
Both EPS and XPS never rots or degrades. So I reused the original insulation materials. However some original insulation was damaged when attempting to prise it away from chipboards that weren't badly moisture damaged, hence the reason for buying a pack of 8.
Or you could use the P5 t&g chipboard flooring units that have the insulation board bonded to the chipboard. These units were included in the original build of my property. They seem to offer more rigidy to the floating floor finish, providing they are laid on a flat level surface. But they are more expensive than buying insulation and chipboard separately. So my original build didn't include that 'all important slip layer', neither do my neighbours' properties floors because it is impossible with the bonded units. And my neighbours' floors don't creak or squeek.

Edited by DaveWilks on Monday 5th March 09:25

Hi, I'm confused. Was the original build of your property with the P5 t&g type where the insulation was bonded to the chipboard, or was it the Styrofoam EPS with a separate layer of chipboard on top?

Been a while since mine was lifted but I remember white polystyrene with floating chipboard laid on top. Can't remember if there was a slip layer. I only really suffer from minor squeaking in places. The bigger issue is how the floor is uneven. You can't tell by looking but as you walk around barefoot you can feel a few mm differences in the height of the floor in places. I appreciate you mention how compressive strength of polystyrene can vary and of course chipboard is very susceptible to moisture (highly prevalent in a domestic dwelling!), so I still fail to see how this is an acceptable building method.