Flooring troubles - bit of a weird one...

[petermillard]

Hey folks.

Customer's just contacted me regarding some problems he's having with a hardwood floor in his kitchen - it was laid (not by me) about 12-13 years ago, and recently (over the course of the last few months) the boards have starting moving and cupping, and now look like this:-

All my instincts are screaming 'water damage from underneath' but having lifted one of the boards this morning there's no real sign of anything obvious; the underside of the boards are as dry as the top sides, the moisture level in the cement substrate, whilst a little high, seems consistent across all the areas that I could reach. Obviously it's a kitchen, so there are all kinds of water and waste pipes around the backs of the cabinets, but as far as I can ascertain none of these are currently leaking, and show no obvious signs of having leaked.

So I'm a bit stumped; the boards are held together with thin metal clips, and those that I've exposed do show some signs of surface rust (and you can see a kind of 'tide-mark' stain towards the bottom of the lifted board in the last photo above) so my water theory is still my favourite, but if anyone has any idea what else might have caused this kind of movement, or if anyone's experienced anything like it before, I'd be glad to hear about it.

And second question: I haven't come across this type of floor before, where it's all held together with metal clips - is this something that's currently available, or just something that was popular a decade or so back? And how do you lift the boards without mucking everything up??

As always, all info and opinion much appreciated.

Cheers, Pete

 

[Jacob]

If they've been good for that long it can only be a new source of damp from below, or (less likely) a new high level of dryness from above.
Perhaps a one off flood which hasn't fully dried yet? Leaky pipe?

 

[Eric The Viking]

+1 for water damage.

It's been very wet this summer. We've had extraordinary amounts of movement in the panel doors in the house. Any leak (or big water spill) that put water under the flooring wouldn't have dried very fast at all, because of the RH.

Did they have a big spill they haven't told you about? I had a problem a while back with a laminate/MDF floor in our downstairs loo: the leak was from a compression fitting* in the cold feed to the toilet cistern, and was running down the back of the pipe (where it couldn't easily be seen), through the hole cut in the flooring and spreading out underneath, on top of the green plastic cushioning material, which is waterproof. The boards swelled at the joints, but happily went back to almost normal when they dried. I don't think real wood will respond as kindly.

I note the bitumen paint under the flooring - if that's what it is, it will trap any water underneath the boards. There's also quite a bit of staining around the joints, implying it has been pretty wet at some time in the past.

I think it's a combination of a spill/leak and the abnormally wet summer.

E.

*I hate plumbers who think PTFE tape is for compression fittings!

 

[AndyT]

Have you asked the customer how they have been keeping it clean? If they have been wet mopping it, some water will have gone underneath through those wide open T&G joints, leaving the underside damp and expanding. It really does not look a very practical choice for a kitchen, IMHO.

 

[petermillard]

Cheers guys - confirming my thoughts tbh. Customer is adamant that there hasn't been no one-off flood of any kind, though I didn't ask specificaslly about a 'big spill' - good point also re. mopping the floor once the boards have started to open up as that certainly wouldn't have helped!

My first suspicion was a leak of some kind from either the sink/washer/dishwasher, all situated at one end of the kitchen, but once I took off the kick-boards there was no obvious sign of any such - I'd been hoping to find the 'smoking gun' of a dried-up watermark or something similar, but no joy.

It's a closed cell foam underlay underneath the floor btw, so would definitely hold any moisture that got underneath the boards, and probably all the more reason to suspect water ingress from above - if it had been a leak from an appliance, then I'd have expected any water to go under the underlay i.e. between the underlay and the cement floor, where the underlay would keep the water away from the boards themselves.

The grey-ish staining on the board surfaces are a sign of general wear, together with more water than perhaps is necessary being used to clean them - i've come across this many times in kitchens with hardwood floors, it's rarely very deep and you can sand it out easily. Don't think I'll be able to sand out that cupping though, even if I did manage to pull the boards together again

Thanks again, Pete

 

[Eric The Viking]

It might be worth taking one of the worst and putting it in a dry location - airing cupboard or similar - to see if the cupping reduces. It'll probably split, if it does, it wasn't me who suggested it!

TBH, I think the most sensible thing would be a new floor covering of some sort.

E.

 

[RogerS]

There was a system called 'clip'n'click' or similar a few years back. Grooves in the underside of the boards. 'Clip'n'curse' I called it. But looking at the massive gaps between the boards, i'd be surprised if it was this system as they really held the boards tightly together.

Ah, found the thread here clip-and-click-t8369.html?hilit=curse

 

[wabbitpoo]

The question really is, what can you do to make a good floor again, surely? The answer appears to be "nothing" as its kinda shot by the looks of it.

You could take them all out, run them thru a PT and get them flat again I suppose...

Worrying how easily you appear to have got that one out from the middle! So much for those clips.

 

[jasonB]

Are there any bare copper pipes running through the screed? Over time the cement will attack the pipe and give pin hole leaks, just enough to raise the MC.

J

 

[petermillard]

The floor extends through the kitchen into the adjoining dining room, and is only affected in the kitchen area - at least so far. And no, there's no chance of resurrecting this floor - the customer's accepted that it needs replacing - I just want to be sure that whatever caused the problem wouldn't happen again to the new floor, 'cos that would be *so* disappointing :/

Thanks for the info on 'clipandclick' - that website doesn't appear to exist amy more, so presumably the system wasn't a huge success FWIW, pulling up that single board was a total pig to do - the clips held it in place very securely, even though the boards were very 'gappy' at the non-clipped end; I don't think it's going to be a easy job to lift this stuff up!

Re. copper pipes in the screed - again, good point, but as far as I can tell all the pipework comes in above the cement floor. Also, the wooden floor is separated from the screed by the closed-cell foam underlay, which I would expect to act as a barrier, no? The moisture content of the board I lifted was very low on both sides, so I think it's something that has happened, rather than something ongoing - hence my suspicions about a flood or leak of some kind.

Hey ho.

Many thanks for all the comments & opinions.

Pete

 

[Sgian Dubh]

... The grey-ish staining on the board surfaces are a sign of general wear, together with more water than perhaps is necessary being used to clean them - i've come across this many times in kitchens with hardwood floors, Pete

You may have offered up a clue there to another possible cause of the cupping, that is, moisture cycling and what's known as either compression set or permanent set. The similarities between the problem you've described along with your images, and the information below are interesting. Slainte.
**************************************************************************************************************
It was common in the British Victorian era to make large heavy pine, oak, sweet chestnut, beech or sycamore kitchen tables for staff to prepare food in grand country houses. For hygiene reasons, and at least once a day, it was normal to scrub the table top with hot water mixed with a little vinegar or salt, and then left to dry.

Each application of water to the top surface and the subsequent drying is a moisture cycle. The wood cells near the top surface of the wood absorb a little water and swell, then dry and shrink again— the underside of the table top always remained relatively dry as it was never soaked with so much water. The result is that the cells near the upper surface gradually distort and collapse taking on a 'permanent set' or 'compression set'. Once they have collapsed they will never again, under normal circumstances in service, revert to their original shape and the upward facing concavity becomes permanent. This assumes that the fixings holding the top to the rails give way under the stress; the alternative, if the fixings don’t give way, is a split in the top with the possibility of two separate cupped parts. Permanent cupping can take many years show itself, or it may take only a few weeks or months. Even wiping down table tops covered in a water porous finishe, eg, waxed, oiled or damaged film polishes with a damp cloth every week or two can cause permanent upper surface concavity.

Permanent set due to compression can also occur in things like hammer shafts. Most of us have experience of loose hammer heads or axe heads on the end of the wooden shaft. Often there is a steel wedge at the end of the shaft. The first thought is to perhaps blame the looseness on the wood wearing out with use. This may be a contributory factor, but another candidate is moisture cycling. The wood cells swell as they take on moisture during humid periods which makes the head even tighter. But the hole in the hammer or axe head is of a fixed size and doesn’t give. The wood cells around the circumference of the shaft become crushed and distorted and collapse. Consequently during a following dry period the wood shrinks drawing the circumference of the shaft away from the walls of the hole in the axe or hammer head. Driving the steel wedge into the end of the shaft tightens the head again, but now the already crushed cells around the perimeter of the shaft are tight within the hammer head hole. Subsequent moisture gain of the wood crushes even more cells and, over time, the head becomes permanently loose.

 

[chippymart]

Have you a moisture meter that you can check the floor and the boards?

 

[petermillard]

Moisture cycling may be a contributing factor, but all the cupping and loosening of the boards has happened over the last few months - having behaved themselves for the last dozen or so years. Maybe he's had a new cleaner in the last few months who's being a bit overly enthusiastic with the mopping?? I'll ask.

MC of the board I lifted was pretty low, and near-identical on both sides. A little higher below the membrane/underlay, but dry above it.

 

[chippy1970]

We fitted a couple of those floors years ago made by junckers and absolute rubbish. They come with different size clips according to the humidity levels of the house. Pain to fit and also when the boards shrink in the summer youre left with huge gaps.

Regards the cupping it must be damp or a leak from below as its cupping up. I had to rip up a 150 square feet of solid oak flooring a few years back. It was in a synagogue in Holland park. They had some cheap bodgers in to refurb the place , they had done something to the heating under the ground floor joists then layed the oak. A few months later the floor was ruined. Turns out a hot pipe was leaking and this steamed the floor from underneath. It was heart breaking let alone back breaking scrapping that floor.

 

[doorframe]

Here's the simple solution.....

http://www.youtube.com/watch?v=cLWiJPyA_Lk

Roy

 

[misterfish]

Why has the timber on the left got those dark patches that seem to spread over two or three boards = it looks like the staining you get from protracted moisure contact. It looks most obvious at the front left and as if it has wicked out along the boards. It may, of course just be a feature of the timber.

Misterfish

 

[neilyweely]

Wickes still sell those clips; they slot into slots in the back of the boards and you hammer them home. I fitted a floor with them a few months back and they were a right pita. Ended up gluing a lot of them and using the clips round the edges. Just to keep customer happy (lets hope he doesn't read this. I am still finishing the other jobs there and the floor is fine, so....)
Anyway, they do appear to be somehwt current.

Neil

PS I had some cupping like that recently around an air con unit built into the wall of a conservatory. Could it be this, or anything like it?

 

[Sgian Dubh]

Moisture cycling may be a contributing factor.

I think you are probably right and the cupping only showing up recently suggests there may be a more dominant cause, eg, increased dampness on the underside, or even perhaps drier conditions on the top side as has been discussed. There again, if there has been a change in the wet mopping routine (primarily in the kitchen area where you report the worst cupping), water spillages and so on, compression set perhaps shouldn't be discounted entirely. Slainte.

 

[petermillard]

Just a follow-on from this. Managed to start pulling up the floor yesterday; half an hour in and there's moisture under the boards, another half-hour pulling the washing machine out and there's water dripping from the inlet hose...

So no great surprise; another half-hour and the leak's fixed. Everything dried out nicely overnight, and by the end of today there was a new DPM, new underlay and a new floor. And a happy customer, which is what counts.

Cheers, Pete

 

[chippy1970]

Pete

That's usual , a builder I worked for years ago always recommended to his customer's that they checked dishwasher connections around 6 months after the kitchen was fitted. We found that the rubber washers in the hose ends shrink with age then they start to drip.

Sent from my HTC Desire S using Tapatalk 2