Mixing chipboard and tongue-and-groove boards? How to make it even?

[raekan]

Hello,

I'm working on an old subfloor in the kitchen where we've had to remove some boards for water and electricity. These are 28 mm. Many are still in place, and the floor is stable and nice. Where I now have a hole (about 140*225 cm), I lack enough good boards to fill it as they broke at the tongues. I was thinking of laying particle board there, but these are only 22 mm. Can I lay that and then another board on top to even it out, or should I install new tongue-and-groove boards? I think it will be difficult to lay them because the hole is in the middle of the room; i.e., hard to fit the planks at the end. Can I skip the last tongue then?

Removing the remaining boards and replacing everything with particle board feels wrong and wasteful. It should also be noted that the joists will be reinforced with screw-glued plywood at the holes, so the load-bearing capacity of the subfloor doesn't matter. Then parquet will be laid on top.

So - can you mix floor types, and how do I even out the differences? Or should I buy new tongue-and-groove boards?

 

[Testarn]

There shouldn't be any problem laying floor particle board and then a 5 mm oil-hardened fiberboard before a little leveling compound for the correct level.

 

[maah]

In that case, place the chipboard with a few mm distance from the tongue and groove floor so it can move.
But seal the joints with latex sealant before self-leveling

 

[tergo]

there are also 6mm boards and possibly you can adjust with lumppapp if needed

 

[raekan]

It should not be a problem to lay chipboard and then a 5 mm oil-hardened wood fiberboard before a bit of leveling compound for the correct level.

Thanks for the answer!
Is the oil-hardened board mainly for leveling compound? Or is it the board to use for other reasons?

 

[fribygg]

Thanks for the answer!
Is oil-hardened board mainly if you're going to apply self-leveling compound?

22mm chipboard and 6mm floor gypsum should work excellently if you don't want to get 28mm floor timber to patch with.

 

[raekan]

22mm chipboard and 6mm floor gypsum should work excellently if you don't want to get 28mm floor wood to patch with.

Any advantage of floor gypsum over the above-mentioned wooden board? It will only be wooden floor on top.

 

[fribygg]

Any advantage with floor gypsum over the above-mentioned wooden board? There will only be a wooden floor on top.

It is intended to be laid on floors, can be self-leveled if needed, is likely easily available at the same place as chipboard flooring.

 

[mexitegel]

Sounds like it might just be easier to buy a stack of spontaneous lumber and put it there. With that width, you might even be able to press it in without cutting the tongue on the last board.

 

[raekan]

I have purchased floor chipboard anyway for simplicity's sake; it will hardly need to be cut to length, making it convenient.

Follow-up question to the collective expertise: Regarding the elevation, can you place the thin sheet under the floor chipboard, only on the beam? Or do you lose the function of increased stiffness to the beams that the floor chipboard provides? In other words, must the floor chipboard be glued and screwed directly onto the beams without anything in between? I received the suggestion to, for example, reuse masonite from the ceiling that must be demolished anyway, hence the thoughts.

Thanks!

 

[Testarn]

Thanks for the reply!
Is oil-hardened board mainly for when you're going to levelling compound? Or is it used for other reasons?

Well, I wrote that to avoid using the brand name Masonite... 😜
If there is floor gypsum in 6mm, it should work as well.

Edit: noticed that this post/reply went out a bit late... 🥴

Regarding chipboard or Masonite on top, I don't know, but guessing that you need to glue to the joists and each layer to the chipboard if it's going to cooperate.