Hardwood flooring

[FirstTimeBuyer]

Hi Guys

We recently had installed 18mm think hardwood flooring to the downstairs.

Now we've put the central heating on the flooring has started to rise in the front room only.

The joiner has nailed the hardwood to the existing floorboards and allowed for a 12mm movement gap to the edges. There is no membrane / underlay as we were told 'secret nailing' was the best method by the shop.

An added problem I have is that my subfloor is often wet (50mm of water) due to the clay soil in my area.

The central heating being on is drawing the moisture from the subfloor up into the house and expanding the flooring.

What can I do to solve the problem? If we did have underlay or the self adhesive membrane would this have stopped the moisture from rising?

Please help. I look at all the other threads but no one seemed to have the added water problems.

Thanks

 

[WoodYouLike]

An added problem I have is that my subfloor is often wet (50mm of water) due to the clay soil in my area.

That's not an added problem, that IS the problem. Adding a DPM ontop of your existing floorboards would not have solved this problem, it would have caused the existing boards and even the joist to rot.

Solve your wet clay problem (don't ask me how, not a builder or construction expert) and you will solve your floor problem

 

[FirstTimeBuyer]

Thanks,

Two ways that can resolve the water problem are to either dig a gravel drain to encourage the water to flow away or to install a sump pump and pump the water out when it gets to a certain level or at regular, say 3 month, intervals.

The first option requires access to the subfloor, which is limited now the oak flooring is down and is a fairly big project in any event. The second will mean that there could be water present before I get a chance to pump it out.

Is it the case that even if I provided more room for expansion that this would still be a problem. I noticed somewhere you had written approx 4mm for every 1m of floor, which for my house would mean approx 16mm. Could this solve the problem?

Thanks again for the help.

 

[WoodYouLike]

Just a bit I think. Your solid floor will keep reacting whenever there is water underneath it so expanding the expansion gaps might be a temporary solution

 

[FirstTimeBuyer]

Had a chat with the joiner yesterday. He thinks we should leave the the flooring for another 3weeks and see if the expansion gets any worse.

Then, assuming it hasn't got any worse or it has reached a limit, remove the outer most boards and increase the expansion gaps to relieve the 'hump' in the middle, possibly using beading to cover up the increase gap.

Are we right in assuming that the expansion does have a limit, or will the floor keep expanding into whatever gap we provide. In which case any amount of expansion gap would not be enough and it would seem that my house is not suitable form natural wood flooring.

Thanks again for your time you've been really helpful.

 

[WoodYouLike]

Sounds like a good plan.
The limit of expansion is related to the humidity and direct contact with moist. In worst case scenario your floor will keep absorbing moist from its surroundings until it starts rotting - but you would notice this way earlier of course by 'mushrooms' appearing etc.

It is just to show you that in your extreme circumstances it is hard to say what the maximum would be.