visqueen ok between nailed oak & ply/chipboard subfloor?

6 Jan 2010
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United Kingdom
Is visqueen suitable to lay between a solid oak 160mm (W) x 20mm thick floor in long random length boards on a subfloor which is majority 20mm marine ply and an area of chipboard at the entrance hall area.The floor will run through from lounge, entrance hall and into the bedroom of a 1 bedroom basement flat (45 sq metres approx.), secretly nailed to the subfloor?

This is a major remedial repair for an expensive floor which was laid only 9 months ago during severe winter and cupped seriously. The fitters started fitting the minute the wood was delivered, so there was no acclimatisation but the company have blamed atmospheric conditions at the property, and take no responsibility.

So I'm having to spend another £1,000 on an already £6,000 floor to remove and replace all perimeter boards and to lift and relay the rest of the previous fit which is now badly cupped.
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Firstly, there are services which can help in this situation and prove one way or another exactly who might be at fault and it's most often down to the fitter. The fitters are responsible for taking moisture readings, ensuring acclimatisation and providing the correct suitable subfloor and fitting technique. They are also responsible for recording atmospheric conditions (relative humidity) to ensure the flooring is installed correctly. Without knowing any real details, i would be 99% certain that your problem lies with the fitters.
Wether you want to battle it out with them is another matter but these things can be swift with the right person behind you at no cost to yourself.

Secondly, visqueen is a definate no. Was this recommended to you or your idea ?
And in addition, it is lilely that the whole floor is installed incorrectly so no point in trying a quick fix.
You need further advice before you proceed !!!!
Basement as in below ground level?
Test the base of the walls to check moisture content as well as the boards.
Check the humidity as well.
Quite common for below ground areas to have moisture trouble and normally solid wood's not recommended - engineered only and then if moisture / humidity is okay.
Contact BWFA (british wood flooring association) - they may be able to help at least with an inspection.
The floor was installed by the suppliers professional fitters as part of a contract price. I reported the cupping, a Director visited and wrote me a letter blaming atmospheric conditions and poor heating during the Winter months.

I tried to sort it out amicably but had to threaten them with the Sale of Goods Act since the floor was not fit for purpose as a floor and the installation did not show durability. I did not take them to court since I expected them to reach an agreement. They are members of NWFA if that's any help to me?

It took the company 2 months to get an 'independant' inspection during which time the floor got progressively worse and was about to pop at 100mm risen height in places, and the board at the front door had to be chiselled out to stop blocking entry. All bay window woodwork and plasterboard wall corners have been stretched out of position as the boards have sought somewhere to expand.

I expected the company to at least show good will by relieving the tension at perimeter boards, but I could not touch the floor in case it became a legal case. They stalled and in my opinion sent in their 'independent' inspector to do a stitch up report. The inspector actually reported back to the wholesalers/manufacturers (not immediately to the retailer/contractor who imho are responsible and with whom I have the dispute; they sold me the floor and fitted it!).

Remember, I'm gutted at what's happened to my beautiful (and expensive) floor.

The report has inaccuracies such as stating there was a weeks acclimatisation; truth is, the job took three and a half days (last job before Christmas break) and started laying from opening the packs on delivery, no acclimatisation. On the last day of the job, fitting the perimeters, the wood was kept in an outside hallway and brought in to the flat as needed. The fitters did not have any moisture or humidity reading equipment at time of installation.

It is the fitter who is now going to lift and relay the entire floor (£600 labour), plus 4 packs of new timber I have had to buy to replace damaged perimeter areas during lifting (another £400) who has recommended visqueen between the 20mm oak and the 20mm marine ply (with chipboard in about 20% of the underfloor, mainly at the hall and front door). I've read that secret nailing is not thhe best grip into chipboard, the green stuff 18- 20mm.

It is a basement flat in a Victorian terrace (i.e. garden flat) but has level areas to front and rear (i.e. it is not subterranian and there are no external or internal drainage problems).

The floor has been laid up to the skirtings, not under them, and there are mouse moulding trims which the inspector did not remove to check the lack of expansion. There was no moulding at the fireplace, so he was able to report on that!

Excerpts from the 'independent' report:

" On the day of the inspection we found the moisture level to be 11.4% @ 62.2% @ 22C. These readings and conditions on the day of the inspection have no bearing on what they may have been when any problem arose.

We could not check perimeters for expansion gaps as skirtings were fixed as were doorchecks. At the radiator pipes we could see that there has been a reasonable gap left but the flooring has expanded and pushed against the pipes and it has also pushed against the fireplace.

We do not feel there has been enough of a gap here to start with. The flooring is layed running through and through with no expansion gaps between the rooms, it is recommended that there should be expansion gaps between rooms.

.....The fact that the problem has occurred after installation confirms that something in the environment is causing the cupping. It was also evident that the flooring has expanded throughout the installation .....

Real wood will perform best when kept with a relative humidity range of 45 - 55% @ 18C with a moisture level of 12%. As the relative humidity and temperature were high on the day of the inspection it would be safe to say again that the flooring is being influenced by something in the localised environment.

We therefore confirm that no manufacturing defect is contributing to any of the problems in this case and that all are contributed to the localised environment"

So I get the message that visqueen is a waste of time. Why?

Also, how do I acclimatise this new batch of wood which will be used to replace the perimeter boards that have to be chiselled to lift them? Do I keep the heating on at constant, open the packs and lay out the boards loose or what?

Many thanks in advance. I am not a legal person or public speaker and shyed away from representing myself in court, and I was told I would have to pay a lawyer and costs if I lost the case. I don't think my buildings insurance covers the floor or poor installation.

I'm personally taking the extra £1,000 hit on the already £6,000 floor hoping this fitter can sort it (even though many individual boards are permanently cupped so that anything level sat on them rocks enough to annoy).
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Hi there,
Thanks for the detail but to help you get to the bottom of this, a little more info from you would help. From what i understand so far the fitter is completely at fault here and you should have the whole floor replaced at their cost or at least your money back.
You should never be pushed into a corner nor have to worry about legal costs, you don't need a solicitor here, trust me.
And in the meantime, be patient, i know it's hard and don't pay them a penny for anything if you can handle walking around on this dodgy floor for a little longer.
You can have your own survey done by a pro who has all the necessities to take this lot to court. He wil only charge for the survey which might be £200/£300 but will not take it to court if there are any doublts. He will only take court action if he "knows" he will win and in these cases it realy is an open and shut case. He is on your side!!
In most cases like this, his survey and a letter to the fitters/suppliers is all that is necessary. you will get your survey money back and a brand new floor throughout, without ever having to go to court.
Take plenty of pictures and make sure to save them or print them off. And tell me, i missed or havn't read aout the sub-floor. I need to know....
1, Is the subfloor concrete or timber joists ?
2, Who laid the marine ply ?
3, slightly better explanation of the woodchip, how it is fixed and to what, and how old it is.
4, Is there or did the fitters use any form of membrane under the marine ply? or on top ?

I know you have explained a lot so far but with this info i can help you decide wether to get your own survey carried out.
If you go ahead and have the perimiter boards replaced you will have further trouble guaranteed !! and will wish you hadn't.

And don't worry about their survey, it hasn't been carried out correctly either from what you describe.
The property is a letting flat. It remains unoccupied and I am receiving no rent at the moment - loss of income - because of the floor situation.

The reason for the floor being replaced in the first instance was because there had been a leak on the rising main in the bathroom causing water ingress and rising damp. In an insurance repair all affected areas were stripped out to 1 metre wall height, floors and subfloors removed, damp proofing injection treatrments and dehumidifiers used to dry the flat out.

The subfloor is a concrete screed with 2 inch wooden battens onto which the underfloor sheets are screwed. The original underfloor had been marine ply throughout.

To cut costs in my opinion, the wood rot contractors laid chipboard underfloor at the entrance hall, extending 2 metres into the lounge and bedroom on either side (about 15 square metres). The original marine ply in the majority of the lounge was not affected by the water ingress and so was not lifted. In the bedroom there had been teak block parquet which had been single block bitumen laid and I insisted the subfloor be replaced like for like (i.e. 20mm marine ply ). So, the majority of the 45 square metre lounge, hall and bedroom underfloor is 20mm marine ply, but at the affected area and treated area they put down green chipboard (18mm/20mm??). In hindsight, I know I shoud have demanded like for like throughout but this was a nightmare of an insurance job and it was a huge effort to get anyone to turn up to do any work at all. A relatively small domestic refit dragged on for 14 months!

I now know that chipboard is not that good for secret nailing since the board tends to not hold the nail. The replacement area of chipboard is at the affected areas (I was assured this would be okay by the rot/damp proof contaractors).Crucially, this is also at the small entrance hall to the flat from an outside common stair well which is draughty and cold. It is no surprise here that the floor has lifted and the first board (160mm wide) at the front door foot plate curled up and had to be chiselled out because the door wouldn't open. The door into the bedroom won't close at this area either because the floor has risen and it can't swing shut, even by forcing it to scrape against the boards. In most situations I suppose you would just shave and rehang the door?

The floor was laid by the flooring company's fitters at contract price negotiated and signed by me with a budget allocation from the insurer and the insurer having chosen this company from 3 quotes which I solicited. On completion, I was happy with the installation and went abroad on business for 4 months. During this time my wife had keys to allow access for a second skim coat plaster which had been botched first time, and for other small snagging works.

The central heating was on constant for the few days while contractors were working and was on timed at one hour in the morning, one hour at night at all other times. This was to keep the pipes from freezing, but also to allow the plaster to dry and bond (which it hadn't done first time).

There is no membrane between the new oak hard wood floor and the underfloor to which it is secret nailed, and no membrane was placed on the subfloor concrete screed.

From abroad, my main purpose was to hassle the insurers to pay up because I had been personally invoiced for the floor and payment was long overdue. They were paid in full in April, and I came back to UK early May.

The week before, my wife had noticed a spring in the boards at the entrance hall and commented on it. I looked around and noticed that the mouse moulding had lifted and it looked like the floor was pressuring against perimeter walls. I informed the flooring company immediately and a Director visited within the next 10 days where he noticed and reported that the floor was cupped but could be fixed by lifting perimeter boards and allowing the floor to settlle. He said he would not "hammer" me on the price, to which I said it was not my responsibility since his company supplied and installed the floor, not me!

Since they had been paid in full, they were in a strong position since this suggests I was happy with the floor even though I was not in the country to inspect it at time of payment. Anyway, no matter the time sequence, the floor was still not fit for purpose and did not demonstrate durability.

I researched the Common Law of Scotland & Sale of Goods And Services Act 1982 (As Amended) and looked into Small Claims and Summary Warrant court procedures and wrote to inform the company that I would initiate legal action if they did not resolve the issue amicably. Their response was to contact the wholesalers who, after two more months during which the floor had expanded out of control and was lifted about to pop at 100mm height in two areas. A radiator pipe was being so compressed by the movement of the wood that it was about to force the pipe off the radiator and this was in an area which had been laid to new marine ply. It was doing the same to and area which was being laid to existing marine ply. There are creaking noises throughout when you walk and whacking sounds whenever the heat is put on or cools down.

I spoke to the wholesalers and explained that my dispute was not with them and they agreed. However, they still advocated an independant inspection to check the integrity of the wood and find out what went wrong and I allowed this still believing the company who installed the floor would back down.

The inspector cautioned me that he was fully independent and that I could not give my opinion as to what might of gone wrong, then took his readings and measurements, about 20 photos, and asked me factual questions. I received a copy of the report from the flooring company (not from the wholesalers who I found out paid for the inspection "because the retailers are very good clients of ours". The photos were not forwarded to me, and I didn't take any of my own.

The floor became so alarmingly risen, and I felt defeated by the report, that in exasperation I got someone to split the boards at worst places and to chisel out perimeters at length of one wall in the lounge and one wall in the bedroom. The floor seemed to be mainly expanding in one direction, no doubt the direction by which it could release itself from the secret nails. There was sign of rust on some of the relatively new nails which I suppose suggests either moisture in the new underfloor ply and chipboard, or moisture/condensation at the base of the newly supplied oak floor boards (or a combination of both?).

The flooring company had simply ditched me having forwarded the report and I had to chase them over 2 weeks for a quote to make remedial repair. They gave me a vague quote (without revisiting the property) with payment in advance for what I thought was a deliberately punitive £1,500 which only mentioned appropriate fixing method to perimeter boards where required and did not even itemise how many packs or square metres of floor I would be paying for.

I need to get the flat let - I'm just about broke - and I have a tenant waiting who has already been postponed one month. She has now been promised occupancy by 1st. October. I have also bought just under 7 sq. metres of new flooring at £400 (from the same company who did the botched job; there were no other suppliers to match the wood; the wholesalers don't supply to non trade, I checked) and lined up my own fitters (£600) to lift the entire floor and to relay it using the new boards at the perimeter because these will have to be damaged to lift the floor. Also, new holes will have to be routed on new boards at radiator pipes.

I have unpacked the new boards and laid them out loose hoping they will acclimatise to the environment which is neither atmospherically damp or cold. Obviously, I know I will not have a perfect floor and there is a huge risk that further expansion and cupping will take place.

This is all very heartbreaking, especially when I see the new boards 100% level in comparison to the cupped boards which for example when you look at the end length mouse mouldings across the width of any boards there is shadow and looks like a series of small peaks and troughs. You can feel the cupping throughout as you walk, never mind the extreme areas of lift which had to be broken open before my radiators got ripped from their pipes!

There is also the fact that I am personally £1,000 out of pocket for an uncertain refit with no guarantee of success. It should not be relevant that the insures paid the initial installation even though the claim has now been closed as full and final settlement.

The flooring company are reputable - that is why they were chosen by the insurer, even though I also knew they had a good reputation. I expected better of them but perhaps this is sharp business practice in a recession, even though I am told they have plenty orders at the moment.

Apart from the independent inspection, much of the background information is unknown to the flooring company. However, they sold me a solid oak floor with wide boards (160mm) (I now know, not the most suitable material) having measured up a basement flat, and the nature of underfloor being part chipboard and majority marine ply was evident to the fitter before installation. Also, there was no acclimatisation except during the three and a half days fit straight from the pack and delivered from their outside storage yard in the worst winter in 30 years, and the fitters had no moisture, humidity or temperature equipment, even if the independent report states 'Yes' to 'Boards Checked prior To Fitting?'.

Thanks for your advice which is greatly appreciated. I don't know if there's any way back for me with the company from this situation - stable door is open and the horse has bolted? - but I am certainly not a happy customer.

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