Amtico hollow sound

I had amtico signature lvt fitted at Christmas . They had to come and uplift part of the floor due to hump between 2 rooms a-joining .

they relaid the floor and few weeks later I noticed a hollow sound when I was cleaning paint off floor. before they lifted floor I didn’t have this sound was perfectly fine .

I do have the floor fitter coming out and he said if the floor planks are not lifting and just sounding hollow I have to live with it, it’s nothing to do with them it the concrete which has been fitted beneath which I can sure it’s not that this has been checked by building regs when laid correct dpm and thickenss of concrete etc . Also it had been laid 2 years under cover before I had Floor laid due to running out of money for flooring .

he said if it was the self levelling compound the the floor plank will all be lifting pushing upwards like little mountains .
It’s not the full plank that is sounding hollow it’s parts of it and only in the area lifted to correct the bump 3 sqm. Again not every single plank.

They laid the self levelling compound and relaid floor 30 mins later. Which they said this is acceptable .

if insufficient glue is used would this make an hollow sound ? I do have a plank which you can see lifted from subfloor when pressed .

when dog walks on it you can clearly hear the hollow sound on various planks .

just want some advise for when they come out to evaluate .

Thanks

 

Could be the screes that has stopped to blow (lift) from the original concrete.
It all depends on their prep/material used

Did they do any moisture tests before determine what process they were going to take?

 

No moisture test done .. they did paint a green damp barrier which is normal practice cause they did this on my other room years a go. But I cannot comment if they applied it again when they lifted up the floor and removed all old screed to level it out .
, they did sand again before putting down new screed but unsure if sanded again on top of the screed with laying the floor has I wasn’t there ( I don’t have any issues with rest of the room that’s spot on. It just the area they have redone which i find odd).

 

Sounds like its blown. The repair possibly not done iver a large enough area. As they lift the boards it will keep blowing if its not bonded well

 

So when come out if I get them to remove a couple of planks and do I tap the screed to see if Hollow and if it is that’s proof it’s blown?

 

Can you post some pictures up ?
How old is the house? What is the sub floor ?

 

Yes get them to remove the offenders and see what's what bit if its blown then it'll be likely the screed will come up with the planks

 

*but

 

I’ll take some photos in morning but by eye looks fine . Subfloor concrete existing house is 20 year old and the extension 2 years old .

 

Thanks .

 

He says moisture check and was okay .

 

He says don’t need removing is not lifted only sounds hollow I said why not lift to see adequate glue is glued. He say can cause more issues doing that. I’ve asked him to send amtico out