ᐅ Installing vinyl flooring as a floating floor over a floating cork underlayment?

Hello everyone,

First of all: there is no underfloor heating.

We have chosen a vinyl floor that will be installed as a floating floor. Currently, the rooms in question have floating cork flooring. In terms of overall height, it would be ideal to lay the vinyl on top of the cork, so the floor level matches the tiled hallway floors.

The vinyl supplier advised against installing one floating floor over another. Their reasoning: the two floors might move against each other. However, since both materials actually slide over each other, I’m thinking: even if that happens, so what?

I’m actually considering slightly roughening the cork surface because the two floors really do slide well against each other.

So, two questions:
1) Is floating on floating acceptable?
2) If yes to 1), should the cork be roughened beforehand or not?

Does anyone have experience with this and can share some advice? Or could an expert like [USER=28384]@KlaRa provide some brief feedback?

Best regards

We did this in our very first rental apartment. Installed over a floating cork floor, also laid floating. Never, ever again! After 6 months, with a lot of effort, we had to remove everything again... it moved and shifted massively. Gaps and cracks appeared everywhere.

schubert79 schrieb:

We did that in our very first rental apartment. Installed a floating cork floor over another floating cork floor. Never, ever again! After 6 months, we had to remove everything with great effort… it moved and shifted significantly. Gaps and cracks everywhere.

Were the gaps and cracks at the edges, or elsewhere?

chand1986 schrieb:

Hello everyone,
I have two questions:
1) Is it okay to install a floating floor over another floating floor?
2) If yes to question 1, should the surface be roughened or not?

Does anyone have experience with this and can share their insights? Or could an expert like @KlaRa provide some brief feedback?

Best regards

Answer:
An existing floor covering, especially if it is loosely installed as in this case, is not a suitable subfloor for installation!
Of course, you can install whatever you want in your own home. However, in this case, the decision goes against the technical guidelines.
These guidelines exist to prevent potential problems and to avoid them as much as possible.
Therefore, the answer to question 1 is no.
Question 2 is no longer relevant.
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Regards, KlaRa

KlaRa schrieb:

Answer:
An old covering, in this case even loosely laid, is not a suitable substrate for installation!
Of course, you can install whatever you want in your own home. However, in this case, the choice goes against technical standards.
These standards exist to prevent and ideally avoid disadvantages.
Therefore, the answer to question 1 is no.
Question 2 is thereby resolved.
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Regards, KlaRa

Thank you for your answer.

Now, for example, with bonded substrates, covering over is quite common, and I have not heard of any issues with tile-on-tile installation.

What problems could I expect with “loose on loose,” and why might it be a particularly bad idea in my case?

>For example, with bonded substrates, overlaying is not that uncommon and I have never heard of any issues with tile over tile.<
Response to this:
I have never heard of loose-laid wall tiles either.
Both wall and floor tiles can be primed after proper degreasing, skim coated, and (in the case of wall tiles, immediately) installed using a reaction resin adhesive.
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>What problems could I expect with "loose on loose," and why might it be a particularly bad idea in my case?<
Response to this:
“schubert79” already described one of the unpleasant consequences of such unprofessional installation!
Especially with so-called "click systems," the locking mechanisms are often designed just enough (note: to save costs) to keep the element functional.
The ALLOC system at that time was excellent but expensive to replicate due to existing patents.
Today’s edge locking systems are adequate, but only on solid substrates that do not tend to develop an "uncontrolled movement" after overlaying.
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Best regards, KlaRa