Just wondering if anyone has ever had an Oldroyd XP plaster membrane in their house to fix a damp problem? And if so, did it work?

I've got damp from condensation in my house. It's mainly in my kitchen, and a bit under the stairs. I live in an end of terraced house and it only really effects the wall which has no house adjoined. A damp specialist company came round and said they could install an Oldroyd XP membrane which allows the wall to breath whilst preventing moisture to collect on the wall. They've quoted me £1400 (inc. VAT) to strip off the wall plaster floor to ceiling on one wall and under the stairs, put in the membrane and then replaster it all and put back the skirting boards back on. I think this is a decent price considering the work involved, but I just want to make sure it's going to be money well spent. I know it won't completely cure the problem, as the root causes (no ventilation and not much heating) will need to be taken care of. But i'd just like to hear any positive stories from it to see if it's worth considering ...... :)

if i remember right, olroyd p is a tanking membrane used in basement waterproofing...
it allows the water to drain down vertically behind it (letting the wall breathe etc) but the water needs to come from WITHIN the wall, or the other side of it at least... e.g. basement (underground) walls....

so ive googled olroyd 'xp' and its the same stuff...

condensation comes from within the room and condenses on a cold hard surface... the membrane may well create enough of a warm surface so that water doesnt condense on it when its replastered but if you dont increase the ventilation, all that will do is cause the moisture to condense elsewhere...

so why havent the company offered a complete solution? and are they offering a guarantee?

there are plenty of ventilation systems around, from trickle vents, to passive air vents to positive pressure ventilation systems.... any of these been mentioned?

1400 quid? how big is the total area to be covered?

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http://www.peterborough-plasterer.co.uk/

just thinking about it, its not a bad idea to create enough of a warmish surface without adding an inch or so of insulation, thereby keeping the skirting boards where they were... and that olroyd membrane isnt cheap, maybe 1400 quid isnt such a bad price...
I'd still have expected them to tackle the ventilation issue though... the heatings up to you...

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Thanks for your reply and looking into it :)

Basically, I bought the house in October 2009 but hardly spent anytime there. So heating was only on late evenings and I was never in the house to air it out by opening windows and doors. I still cooked and dried washing inside, so over the 18 months there's been alot of condensation problems due to this. I wasn't aware of condensation problems before, otherwise I would have made sure I ventilated the house!

Anyway I think the wall of the kitchen will need replastering to get rid of the moisture inside of it. The wallpaper at the bottom of the wall is actually pretty wet. The size of the whole wall they're doing is approx 5 meters wide and about 10 ft high. Under the stairs is pretty small, about 5 ft high and 4 ft wide, but in a triangular shape (sorry i'm not good with measurements!).

i realise I need to tackle the root causes of ventilating the house and putting the heating on, which I am going to definitely do! I've even opened my windows and locked them slightly ajar. But because i'll be gettin the walls replastered, i'm thinking i might as well just put the oldroyd plaster on it aswell? I'm not sure how much it would cost to just replaster the wall, but as the old plaster wil be taken off anyway maybe it's worth puttin the oldroyd membrane on to help with the condensation?

The company haven't mentioned any kind of ventilation system though. Are these any good and are they expensive to install?

Thanks again for replying and sorry for my essay message here! :)

worth a read through if you havent already -
http://www.ultimatehandyman.co.uk/damp/condensation.htm

anyway, the membrane is usually used to combat penetrating damp, not having done the survey i cant comment on exactly what the problem is, but it does seem an unusual remedy for condensation, although only to me, i wouldnt have thought of it...

maybe they want a belt and braces approach which would cover the job for penetrating damp? but certaintly, applying the membrane will raise the temperature of the internal surface slightly by stopping it conducting its heat out through the masonary, sort of a thermal break if you like..

seeing as its an 'end terrace', I'll take an educated guess that its a solid 9" wall as opposed to an insulated cavity wall, so it wont have any insulation in place...

for the price, I think its a reasonable solution however there is one thing to consider...

current building regulations state that if you remove more than 25% of the plaster from an external wall then it should be replastered using a system that will bring the walls 'u value' or 'level of insulation' in line with current regulations...

with this in mind, i dont think (well im 99.99999% positive) that just adding an olroyd p membrane and replastering will satisfy this regulation, you the householder are liable in the eyes of the building inspector, not the damp company.

refer to section 2-requirements, paragraph 5.7, approved document L

http://www.planningportal.gov.uk/buildi ... 010edition

free to download..

information for specifying work to satisfy the current regs is linked within the document, but essentialy it would involve insulating the wall with a phenolic sheet insulation such as celotex or kingspan prior to replastering...

sorry to be the bearer of doom and expense but providing the building inspector doesnt know about it, what he doesnt know cant hurt you...

all this said and done, youre already aware that you need to combat the problem at source, venting tumble driers to outside, fitting passive air vents, trickle vents or introducing a posotive pressure ventilation system are all possibilities...
simply introducing a 6" extractor fan in the kitchen will go a hell of a long way to solving the problem...

http://tinyurl.com/3ojdr24

the above is more on condensation, and a positive pressure ventilation system, somewhere in the region of £500 - £750, used in extreme circumstsances

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http://www.peterborough-plasterer.co.uk/