Bouncing, floating-wood floor

[WoodenVirgin]

I recently extended our house and asked the builder to instal wooden floors in two rooms, one an old room with existing concrete floor and the new room with a new concrete floor.

The warping in the new room is the worst and initially occurred at certain end points where there was no skirting holding it down (ie patio door and internal doorway). He fixed this by putting screwing a strip of wood to the patio door frame to hold the wood floor down. The wood is now warping elsewhere in the room, less than it was to start with, but still noticeably. i'm, concerned the stress being placed on the ends will cause further warping as time goes by.

The warping in the old room is less pronounced and occurs only in one place (just off the middle of the room).

Any idea if this is normal / extraordinary or how I may be able to fix it?

 

[mr_vampy]

Hi Woodenvirgin

You say the new room has a new concrete floor. How long did you wait for the concrete to completely dry out before installing the wooden floor? How is the wooden floor installed? Is it using the floating method, secret nailing or glued? If using floating method, was DPM used?
I'm not a wood flooring expert as I only fit laminate flooring. I'm sure the experts who work with solid wood will provide you with an answer soon. Good luck!!!

 

[mattysupra]

mr vampy, you say your no expert but you are hitting at moister/drying times so that puts you in the top 90% of so called experts that i have to deal with, assess etc, Well done!

As vampy has already asked "how long was the subfloor left to dry?" Or more to the point what was the moister RH reading of the subfloor in both rooms?

Concrete needs on adverage 1mm per day to dry or, in old school terms, about 1" per month to dry! A profesional installer should have moister readings for both your rooms, even if the other subfloor is 20 years old the moister may be to high to install wood without some sort of vapior barrier or surface dpm being installed.

Also what wood are you fitting? Laminate, engineered or solid? ( we should also have moister content readings of the wood but we will go into that later if we need to )

How long was the wood left to acclimatise in the rooms to be fitted?

And as mr vampy has asked, what method of fitting has been used? Floating with glue tongue+groove, floating on self adhesive underlay, floating click, fullybond, nail/battern?

If you can help us with these questions we can help you

 

[mr_vampy]

Thank you for the compliment mattsupra. I was hoping one of the professionals like yourself would come on here and help woodenvirgin out.
Alot of what I know is by research and from reading replies on here by people like you.
I only fit laminate flooring, and even though I know the principles of fitting solid wood, it's not something that I would dabble with as I'm just not 100% confident with it.
As for moisture readings, I think I'll leave you to deal with that if woodenvirgin is able to provide them.
I forgot to ask in my previous reply to woodenvirgin, was the wood flooring acclimatised for 48hrs in the room that they were being laid and also did your builder leave a suitable amount of expansion gap around the perimeter of the room?

 

[mattysupra]

the acclimatized for 48hrs is only true for laminate, solids can take weeks!

 

[WoodenVirgin]

Thanks guys. The concrete floor was laid in August and the wooden floor installed in February but no moisture was reading was taken at the time by the builder who fitted the floor. The humidity readings were 40-43 degrees when read two months ago and the moisture levels were 12%.

The floor is a 22mm engineered oak tongue and groove floating boards that was glued. The wood was left to acclimatise for 48 hours in the "old" room and 2 weeks in the room with the new concrete floor.

The builder did leave an expansion gap round the room (underneath the skirting board). There isn't any cupping (picked that one up while surfing last night), but there is bouncing and gaps between boards.

 

[mattysupra]

The humidity readings were 40-43 degrees when read two months ago and the moisture levels were 12%.

40-43 degrees?? Do you mean humidity was 40-43 % ? I take it this is a air humidity reading and not the concrete moister reading?

And the 12% is the wood moister content? do you know what the wood moister reading was when installed?

Was the heating up and running when installed back in feb or has it been up and running since?

Do you know what the width of the boards when supplied in mm? Box should be very accurate saying for example 20.15cm/201.5mm ? If you do could you measure the width now with a steal rule, not a tape measure?

And one last thing, how smooth was the subfloor? 1mm in 1 meter run out? 5mm in 1 meter run out?

 

[mr_vampy]

the acclimatized for 48hrs is only true for laminate, solids can take weeks!

Thanks!! Learn something new everyday.

 

[WoodenVirgin]

Apologies, yes the air humidity reading was 40-43%.
I don't know what the wood moisture reading was when installed.
The heating was, I believe, up and running when the floor was installed.
The widths vary but I have the measurements for the widest which, on the box, says 300mm. Measuring it now they're 300.5mm (I used a metal tape measure. Is this OK?).
Unfortunately I have no idea how smooth the subfloor was. The new concrete floor was laid before deciding what floor to put down.

 

[mattysupra]

you can use a tape measure if you jump up the scale to lets say 10cm to take the measurment and then - take 10cm off the measurement. This is because the end of the tape moves and is not accurate. Did you do this?

Anyway if your boards are wider than the stated size on the box it means they have expanded. Now if you have gaps in the floor then they must of shrunk! So basically for them to be bigger now than they started out at the factory but you installed floor has gaps i would say that they was fitted with way to much moister in them in the first place. ( does this make sence to you? )

As for the bouncing in the floor i would put this down to the subfloor being uneven. The floor does tend to get a little better over time as the boards do tend to take the shape of the floor but this takes time and does not always happen.

It is hard for me to work out your problem without seeing it but that is what im thinking at the moment. I can do a full report on the failer of the floor with a site visit, but this would be at your cost and not really needed unless your thinking of taken the installer to court etc.

 

[WoodenVirgin]

Yes, I did exactly that. Started at 10cm then took 10cm off the measurement. Also, I understand the logic about expanding then shrinking.

I'm not sure about the sub-floor being uneven though as the boards originally warped at the ends, by the doorways, where there was no skirting to hold them down. The builder has since but some strips on the door to hold the boards down and it is now bouncing elsewhere in the room.

I haven't really thought about taking the builder to court and just want a to find a remedy. Also, I think it may get worse as the seasons go by and it gets damper then drier.

 

[mattysupra]

well we have no reason to take people to court here. It is not your problem to fix either, if the floor is not correct then tell the installer to fix the problem. If then they do not fix the problem then maybe me and you need to talk! End of the day, if you buy a new kettle and it does not do what its ment to do you take it back/ get it repaired etc.