Uneven floor. 12mm chipboard on floor heating before vinyl flooring?

[Gatozen]

Hi,

I'm working on a major renovation. I've installed underfloor heating upstairs. Screwed and glued 22mm grooved chipboard, 16mm pipes, and plates on 60cc joists. The floor is uneven and troublesome, spongy in some areas (due to milling). I suspect that the carpenters I hired weren't careful enough to level the joists before the grooved boards were placed.

When they were finished, they said that all I had to do was level the large depression where there is about a 2cm difference. However, I feel that the entire floor is uneven.

The plan now is to lay 12mm subfloor, screw and glue these to add more stiffness. Then level on top of this and then vinyl click. Thoughts on this? I'm also wondering if there should be anything between the subfloor and the plates?

The original plan was to lay parquet directly on the plates, but it's too much if I now have to add the subfloor as well.

Best regards, Beginner

 

[Dr Benz]

Hello and welcome.

So, have you had the beams completely accessible and NOT checked the skewness/adjusted this?

Or is it the spånet (shavings) that is flexing due to bad milling according to you?

The spånen (shavings) come pre-milled, so it sounds strange if that's the case.

You need to level the floor before laying parquet when it skews so much. But you probably know that.

Don't know if you can smooth out the unevenness and hi it becomes, but I would have been furious to make that mistake when it would have been so simple to get the floor level...

 

[Gatozen]

Hello and welcome.

So, they had access to the entire floor structure and did NOT check the skewness/adjust it?

Or is it the chipboard that's flexing due to poor milling according to you?

The chipboards come pre-milled, so it seems strange if that's the case.

You need to level the floor before laying the parquet when it's that uneven. But you probably know that.

I'm not sure if you can float out the unevenness and get there, but I would have been furious to make that mistake when it would have been so easy to level the floor...

Yes, it seems like that hasn't been done... It was "acquaintances" who helped me, so I can't be too harsh. When the construction started, I was COMPLETELY new, so I didn't know what needed to be done, but now I would have been extremely careful to ensure it was done, of course.

Where it flexes, I have milled extra (across the existing grooves).

Now it is what it is, and I would appreciate help on how to proceed. The advice I've received is, as mentioned; 12mm chipboard (screw-glued), float the unevenness on top of that, and then the floor (vinyl flooring). Thoughts on that?

 

[Dr Benz]

Ok, I understand. I thought it was craftsmen you paid for. But it's really annoying anyway.

But how do you mean that what you've milled would counteract movements? Is the board not screwed tight? Then it might be hard to do anything except start over... it's not good to try to force the board down with large differences. And you’re just moving the unevenness one layer up so to speak...

My solution is unfortunately to redo it...
but maybe there's someone else who has encountered something similar and has a less demanding solution.

 

[mexitegel]

Now it is what it is, and I'd like some help moving forward on how I can proceed. The advice I've received is, as mentioned; 12mm floor chipboard (screwed and glued), level out the unevenness on it, and then the floor (vinyl flooring). Thoughts on that?

That's essentially what can be done.

Under turns, there should be noggins to ensure stability. But it's too late for that now.

 

[HEM2121]

Yeah, it seems like it hasn't been done... It was "acquaintances" who helped me, so I can't go too hard on them. When the construction started, I was COMPLETELY inexperienced, so I didn't know what needed to be done, but today I would have been extremely careful to make sure it was done, of course.

Where it's uneven, I've milled extra (across the existing tracking).

Now it is what it is, and I'd like some help on how to move forward. The advice I've been given is, as mentioned; 12mm floor chipboard (screw-glued), level out inequalities on that, and then the flooring (vinyl floor). Thoughts on that?

The “simplest” is to remove the grooved boards and ensure that the joist is level. We added on to the existing joist to level it. Let new boards for the joist stay inside for 1-2 weeks. Glulam is best but expensive. Be careful to make sure the joist is level; 1 mm makes a difference. If it's skewed in all directions, self-level the entire floor or parts of it.

 

[Gatozen]

Thanks for all the responses. The chipboard is glued and screwed to the joists, and the underfloor heating is connected, so removing everything and starting over is unfortunately not an option. I would have definitely redone several things if I could turn back time.

Unfortunately, these are the current conditions, and I would like to make the best of the situation. I've written down the advice I've received to proceed (12 chipboard+floating+vinyl).

One question regarding that. Should I put something between the underfloor heating and the 12mm chipboard?

Best regards

 

[mexitegel]

Read the assembly instructions for the ROT disc. They should always be followed.

 

[HEM2121]

Thanks for the replies everyone. The shavings are glued and screwed into the joists and the underfloor heating is connected, so removing everything and starting over is unfortunately not an option. I would absolutely have done several things differently if I could turn back time.

Unfortunately, these are the conditions now, and I would like to do the best I can. I've written what advice I've received to proceed with (12 floor chipboard + leveling compound + vinyl).

One more question. Should I put something between the underfloor heating and the 12mm chipboard?

Regards

You must have foamed plastic because there will be condensation from the pipes. As Mexitegel writes, you must follow the instructions for the floor. Did the craftsmen know which floor you were going to lay? They need to redo it and do it right. They should have leveled it before laying the grooved boards. Leveling compound on top of the pipes will remove some of the heat, and it must also be primed before the leveling compound.

 

[mexitegel]

Says who?

 

[Gatozen]

I'm pondering a bit about this with floor chipboard and leveling on it. What is the downside of leveling directly as it is now? It's the entire upper floor that's "uneven." So instead of laying chipboard, level the entire surface thinly.

I spontaneously think it feels "unnecessary" to lay new chipboard and then level a lot on it.

Please help me think 😅

 

[sturnus]

I think that applying "flytspackel" on the whole will repair both the level of the floor and also improve the heat transfer from the heating system.