damp on internal walls

moneyuser

I've had damp problem in my hallway since 2008 and really need some advice as not sure what to do next

Noticed in early 2008 a big tide mark (about 18" high) on hallway wall. Called in some damp proofing companies for advice and they said it was rising damp. Got the work done, which included re-plastering to their special "damp proof plaster" specification.

In 2009 I called them back because there were salts still coming through the plaster after a year (I waited 6 months before painting). They said this was normal and just keep wiping it off and it would stop.

Now 2 years after and I have 4 spots of visible dampness in the corners of the hallway walls. Currently on the main dividing wall between hallway and living room (where the original big tide mark was) there is about a 2" by 10" damp patch in the corner of the wall. No sign of damp on living room side of wall (both sides were re-plastered but I think only injected from hallway side)

Opposite the living room/hallway dividing wall are the stairs with under-stair cupboard. On this little stair wall there is a bigger patch of damp. It extends outwards from the corner into a half semi circle and is about 10”x10”.

The internal living room/hallway wall is single brick with a concrete floor. The house is a terrace. There are no signs of damp on front/back walls or party walls.

The hallway leads to the kitchen/diner, which takes up the whole width of the house and therefore runs partly parallel with the living room. There is a dividing wall with a chimney. There are signs of damp on this dividing wall, such as paint peeling/discoloration and damp readings using a meter. The chimney used to be coal fired but now uses a gas fire.

The house is empty during the day, so there is no heating on. Although the kitchen does have an extractor it is not used but I do open the window when cooking or using tumble dryer. The bathroom has an extractor, which is used.

The damp proof company (peter cox) want £75 to come out and do a survey and take samples. I am convinced they will find some excuse as to why it has reappeared. If I was to get one of their free surveys done I’m also sure they would say it would need treating.

When they came out last year he just put his damp meter where the salts were and as there was no reading said it was ok. This time I got hold of my own meter and have tested the wall and the reading is very high. Further along the wall there is no reading.

Is there anything I can/should do before paying to get them to come out?


Sorry for the long post but I hope someone will answer.

Plasterer

Theres a guy called David Aldred on the forum that really knows his stuff i have PM him to have a look

David_Aldred

Hi Moneyuser,
Thanks plasterer, the design function of the replacement replaster is to hold salts back within the wall and a certain degree of dampness that may still rise up the wall due to the inherent limitations of chemical dpc systems. If the paster is contaminated as you imply then it is not rocket science to determine non compliance with this design function. Additionally if the floors are solid construction the contractor if complying with the chemical damp proof course British Standard BS6576 have checked and addressed any dampness emerging at gaps to the floor / wall joint irrespective of any rising dampness up through the wall itself and protected timber from such dampness.

As you quite rightly point out if the contractor were inspecting the area of concern now "as a new job" with an electrical damp meter they would probably say the wall needs yet another new damp proof course (dpc), the same as they did before. When they first diagnosed rising dampness if this was done with nothing more than an electrical damp meter this was nothing more than a guess for profit on their part as the only way to prove rising dampness was by laboratory analysis of wall samples for each and every wall under investigation.

The problem with just complaining to the contractor is that even if they do come back and undertake some re-treatment this may only be what they feel they can get away with as minimum works to keep you quiet such that they may not notify / address other areas of potential concern that may similarly become problematic at some point in the future if the same situation exists.

Ideally you would have your own independent specialist survey undertaken so you have an expert witness on your side to fight your case against the contractor and you are fortunate in that this contractor is a nationwide company that remains in business who often claim to work in accordance with BS6576. If you do not wish to have such an independent survey then you are left having to fight your own corner as a layperson so the contractor may not be inclined to take as much notice of your complaint.

If you are going to do this on your own without expert guidance, then a good start would be to go the main library where you can read a copy of BS6576 online via the library computers (but you cannot print it all out unfortunately but you can make hand written notes from it). I would then photograph the area of concern with a date stamped camera and write a letter along with these photographs and copy of all documentation to the Property Care Association (PCA) of which this contractor should be a member setting out your complaint and also write to the contractor explaining that you have done this and why. This may start to make the contractor sit up and take notice to at least some degree but this is not guaranteed. The PCA offer an arbitration scheme although I appreciate you mjay not have as much confidence in this as you might compared with going to the small claims court / having somebody look at the problem on your behalf in an unbiased qualifed manner.

You could make a claim via the small claims court but really this would need to be on the back of you having your own specialist report undertaken so you had hard facts from an expert in such matters to back your claim up. Other than the guarantee issued to you from the contractor, you are entitled to have the survey for dampness and the work undertaken with reasonable care scare and skill by persons in such professions in accordance with the Supply of Goods & Services Act 1982.

Please consider having a read of my other posts on this forum regarding dampness, condensation, damp meters, rising damp and chimney breasts which may be of assistance. Specific cases may vary and these are only general comments but hope this helps, kindest regards, David Aldred Independent damp and timber surveyor.

balloo_2

In 2009 I called them back because there were salts still coming through the plaster after a year (I waited 6 months before painting). They said this was normal and just keep wiping it off and it would stop.

---

Salt comes from the builder using cheap sand (sand is sand you might think) but cheap sand does not get washed so the sea salt stays with it and comes out after the build.

missprice

balloo wrote: »

In 2009 I called them back because there were salts still coming through the plaster after a year (I waited 6 months before painting). They said this was normal and just keep wiping it off and it would stop.

---

Salt comes from the builder using cheap sand (sand is sand you might think) but cheap sand does not get washed so the sea salt stays with it and comes out after the build.

thank you balloo i did not know that
is it called sharp sand?
rebuilding a bit of a garden wall and am fairly sure the original builder used sharp sand for the cement mix, cannot for life of me remember the concrete they used but am trying to get same colour so the rebuilt bit looks ok

David_Aldred

Hi,
As indicated by balloo salt can come from unwashed sand (often chlorides) but can also come from a number of other sources such as ground moisture, leaking drains, contaminates within the original construction, industrial pollution, the type of mortar used (i.e. black ash mortar) and products of combustion within chimney breasts migrating into surrounding plasters, etc

The salts can include nitrates, sulphates and chlorides and identification of which is present within a problem area (if any) obviously assists diagnosis. Different types of sands are used for different jobs within the construction industry and what may be suitable for one application may not be appropriate for another but all types can be contaminated if inappropriately prepared / stored prior to sale. Hope this helps, kindest regards David Aldred Independent damp and timber surveyor

moneyuser

Thanks for your detailed reply David.

The independent survey would be the better option but I haven't got a spare £300 to get one done. I guess the £75 they want is to do the tests they should of done in the first place but as it's not independent I really don't trust them.

I will do some more research and read your damp threads.

Chris_Michael

More than likely the issues are to do with internal production of moisture i.e. condensation because the issues that you have are on the colder surfaces. I would look at the production of moisture within the house itself and look at ways to decrease it and/or buy a dehumidifier. you have received some very good advice already and I would also Google a man called Jeff Howell and read some of his comments on rising damp.

Chris

25rts

Dear Moneyuser,

I have a little knowledge of damp proofing having been in the industry since 1986 so would like to add my comments.

Firstly, nearly all companies charge (most more than £75) to undertake re-inspections and I would only go to the PCA if you were unhappy with Peter Cox's findings and proposals. It is a fact of life that on occasion works are unsuccessful.

Assuming that the damp is on the ground floor and not a basement: the plasterwork would normally start to appear dry to the eye in less than a couple of weeks although some salting can continue to appear if the brickwork is particularly damp as it takes 28 days before the render is considered to be fully 'cured'. If the new render at the lower level is of insufficient thickness to retain the residual moisture or if there are any proud bricks, damp patches will persist.

If the plastering was undertaken by Peter Cox and hasn't been disturbed ie by cutting in sockets for example then it is unlikely they wont accept responsibility, if however the plastering was undertaken by your own contractor it is likely that the mix is wrong (this is nearly always the case). Although recipes vary slightly between different companies if you have a look at the Renderguard Gold datasheet on Safeguard Europes site this will give you a suitable specification. You can also download their guide on treating rising damp rather than going to the library to copy BS 6576



Keith

Dry_Rot

Hi Moneyuser,

Peter Cox are a national firm with a long and distinguished history behind them. Whilst all businesses are going to look after their interests, good, well established ones tend to stay that way because they do a reasonable job. Their contract with you probibly includes conditions about re-inspections and such. If I were you I'd book the paid re-visit and see how it goes. You may be pleasantly suprised, there is no benefit to Peter Cox in refusing to help customers with problems, especially in this day and age, what with this forum and others.

Damp-proofing can be tricky and as Keith says, problems can occur. If you are not happy with Peter Cox's explanation after they have had a good look, complain to the PCA first.

I'm a damp proofing specialist and if the PCA ring me up I have to explain myself - so would Peter Cox.

Someone mentioned Jeff Howell? Save your breath - he has nailed his colours to the 'myth of rising damp' In which case you are doomed to suffer from lifting damp, hovering damp or falling dry, because rising damp does not exist!

Independent surveyors are fine - but costly. Use one by all means, but when you need to; after you have explored the full complaints route. Reading reams of David's posts will not make an expert of you and you don't need to be one.

Now where did that moisture come from

Dry Rot

David_Aldred

Hi - I had thought this thread was now dead but saw recent postings to it and therefore have added the following comments for the benefit of the original poster (op) and others who may be interested.

The (op) asked if there was anything they could / should do before asking the contractor out to re-inspect and for this advice was given regarding both where they may read up on the subject of dampness and in particular rising dampness and options regarding obtaining an independent report should they wish to do so / bringing the matter to the attention fo the PCA (Property Care Association).

The (op) does not state they want to be an expert upon the subject of dampness and I agree that they do not need to be such an expert but equally it would be prudent for them to have at least some basic understanding of the subject matter prior to asking the contractor to re-inspect. There is a recommendation to read British Standards at the local library and to also read the background information upon the subject contained within previous posts on this forum which may help assist the client with having such a better understanding of the subject.

Unfortunately the optimism given in previous posts that all contractors will simply hold their hands up when they have been found to be negligent and re-treat the whole property where that negligence is found to be a common fault throughout the area of treatment, is not always found to be the case, even with the national companies. Another problem is the burden of proof with regard to negligence rests with the client and if they are a layperson in such matters simply trusting to the contractor to reveal the full exctent of the problem may be rather naive.

What may simply happen is there is an offer to re-treat a patch area that is obviously visibly failing, followed by the problem that is common to the area of original treatment becoming visible to the client in yet another area a few months later, followed by further patch re-treatment by the contractor following a second complaint and so on and it is not unknown for even the nationals to make several visits to re-treat such that the re-treatment becomes virtually ongoing with the client totally stressed with such repeated visits / re-decoration, etc.

Under such circumstances the client has to put up with the obvious long term stress, disruption upon repeated occasions, pay for consequential damage such as re-decoration on each occasion that the contractor may deny liability for and of course repeated re-inspection fees from the contractor which can mount up over time. This of course assumes that the contractor accepts liability (which they may well not) for patch re-treatement from a layperson without qualified opinion from others to back up such claims.

Complaining to the PCA is an option and if the client has read up regarding the subject matter this will assist with arguing their claim to the PCA who in turn should make the member contractor at least sit up and take notice. My own experience of the PCA arbitration is a positive one, however if the dispute warrants certified independent laboratory analysis of wall samples this would have to be paid for by somebody if the client is not prepared to trust the contractor to undertake their own analysis so there is a limit as to what the PCA will do for free.

The client may also feel that the PCA is a trade association funded by its own members of which the national companies are the major players and not being an expert on the subject matter the client may feel that under such circumstances, such an in house arbitration scheme may not give them the best option with regard to having not only a truly independent opinion of what is actually causing the problem but ensuring that re-treatment goes far enough to address such problems in one single re-treatment process.

Others have mentioned that having an independent specialist surveyor look at the problem is costly but this is often not the case. I know from my own experience that I have looked at problems local to me simply for free in some cases because the client was disadvantaged and I felt morally bound to assist in fighting their case upon their behalf. Normally however the independents do have to charge more than the contractor to inspect because the survey fee is the only income the independent surveyor has since they are not undertaking treatment works that the survey fee can be written off against.

Given that there are only a handful of independents in the country it is often not the inspection fee but the additional travelling costs that bump up the fee so it often comes down to how close you live to one of the independents. However as an example typically an inspection local to me would only be double the re-inspection fee of the contractor.

Given the independent in-depth analysis within such reports looking at the house as a whole not just a current visible area of concern I can only comment that the cost of the independents is reasonable and in court work can form part of the client's claim where negligence is proven when previously denied. Hope this helps, kindest regards to all, David Aldred