Am about to buy a house which has been diagnosed with rising damp. It also has penetrating damp - needs new roof, gutters and some repointing. Also, chimney breast is bricked up with no vents.
I'm wondering at the moment whether to try just getting external problems fixed, unblock chimney and add French drains around house (and probably replaster internally with salt retardant) to see if that solves the problem, rather than have new dpc injected.
Also, it has been uninhabited for c.6 months, so I'm guessing that's made things worse.
Does anyone have any experience of doing this? Did it work?
Provided your mortgage company is not INSISTING that you get the chemical damp proof treatment carried out I would certainly concentrate on maintenance & heating/ventilation aspects before resorting to chemicals. I suspect you will find that your rising damp gradually goes away. I had many of the problems you describe with my house and my damp has more or less disappeared in six months purely by opening up the chimney, taking down ugly secondary double glazing, removing hideous vinyl wallpaper and repairing a dodgy downpipe I wouldn't have thought you'd need french drains - is the ground level OK in relation to the damp course?
as far as I can recall, 3 sides are fine in terms of ground level but there is a patio at the front which I suspect is not helping.
There does seem to be an issue with a concrete floor being laid above dpc (possibly) in the hallway, but I still think that treating the cause is the way to go - ie improve ventilation.
Maybe just add a gravel border to prevent rainwater splashback?
Great to hear that it worked for you, thanks Did you replaster internally or just let the existing plaster dry out?
Just let the existing plaster dry out - the walls weren't in bad nick once the vinyl paper was off and the mildew sponged down! I have lined the walls before painting as they weren't so good that I could paint straight over, however. A gravel border is probably a good idea - I had a seriously bad damp report on my previous property (the word 'saturated' was used) and this was purely the result of poor maintenance (blocked drain) and rainwater bouncing against the wall of the basement well. How old is the place you are buying?
Originally posted by susiecam: How old is the place you are buying?
Late 20's.
Did you have damp on internal walls too? I have to admit that's the only aspect that makes me go 'eek' a bit about the idea of not having a dpc injected. It seems to suggest the foundations are damp....
Hi Gulp, I agree with suziecam, don't rush ahead with expensive damp-proofing. Can you live in the house for a while and try to sort out what and where the problems really are?
in my experience injectable damp courses are an expensive con and a waste of time. What are your walls made of? How old is the house? The measures you list seem eminently sensible for starters, and remember that in early Victorian properties and previous to that, a certain amount of air movement within the house is necessary to allow evaporation.
We were told we had rising damp in our ground-floor shower-room: had the surveyor opened his eyes at all, he would have noticed a dodgy downpipe just outside discharging most of the water around and not into the drain.
Good luck with it.
behind every successful man is a disbelieving mother-in-law
Luckily no damp on the internal walls in the current property, but again in an earlier place I had terrible damp in the main bedroom on the party wall - all clammy & horrible. Wasn't picked up on survey and I didn't notice it as the vendor had covered the wall in a pale shiny paint. It was only when I painted a darker matt finish and notiched that the wall was taking on the appearance of having been splattered with chip fat that I knew I had a problem! The chip fat effect continued to creep until I had a damp shadow running up to about three feet. This was a combination of dodgy old plaster, previous impermeable paint finishes and condensation combined with the poor maintenance of the house next door (their kitchen was behind that wall, house not touched for forty years, leaks all over the place). I tackled all the things I could but I have to say it was still damp when I sold the flat three years later (did point it out to my buyer like a good citizen). The house next door was sold for renovation so I'd like to think that sorted it once and for all.
Rising damp has nothing to do with any damp that is above one metre high.
Rising damp is caused by capillary action. That's the same action that is at work when you mop up water with a tissue or a sponge.
Central heating won't dry it out but it will make the house extremely unpleasent to live in. The air will be dank and condensation will stream down your windows.
Hack off all the plaster up to one metre and then get someone in to inject the walls (or do it yourself). It'll cost about £350 to £400.
If you have rising damp then this is the ONLY cure.
If you don't do it, you'll never sell the house later.
I have bought and lived in four properties all of which were noted as damp upon survey, all of which were inspected by damp treatment companies at the lender's request(all recommended significant and costly work)and none of which proved to be suffering from rising damp at all. This is why I am suggesting that Gulp explores all other avenues before blasting away at the brickwork with chemicals - the solution could be very simple, inexpensive and environmentally friendly! There is a prominent London borough surveyor - can't remember his name I'm afraid - who claims that he has never come across a genuine case of rising damp during the course of his entire career. He claims that there is ALWAYS a simple cause and a straightforward remedy. I know he has a web site - I must look it up.
Susie, the surveyor you mention is quoted on Jeff Howell's website, but the website seems to be down at the moment.
As the house has been uninhabited (and so unheated and unventilated for six months, damp on internal walls could well just be condensation. My mother has what could easily be mistaken for rising damp below her bay window - but she lives in a third floor flat. It has been a persistent problem in this particular room because she doesn't heat it, and always keeps the door and windows closed. It looks horrendous - black mildew and peeling wallpaper.
Rising damp is a scientific fact. It is caused by capillary action and water tension.
If the bottom of the internal walls are damp to the touch, and you can see little white crystals and you go outside and find frost damaged bricks of a slightly darker colour - you have rising damp.
I have injected bricks and you can actually see the droplets of water oozing out as they are replaced by the silicone solution.
Any surveyor that doesn't know that should be fired.
I accept that rising damp exists, in the sense of damp that rises through capillary action. What I'm less convinced of is the wisdom of treating the symptoms by just physically stopping it rising above the level of an injected DPC......
It seems to make more sense to treat the cause of the damp rather than the symptoms, by improving ventilation etc....doesn't it?
I am obviously not an expert, though, and am very grateful for opinions and experiences
Lee33 - No one disputes that bricks are porous, or that capillary action can draw water up through them, but rather that because the distance the water is drawn up is limited by gravity and evaporation (provided you have the proper breathable paint coverings) the damp is confined to (at most) one or two bricks above the wet line. Actual cases of ‘rising damp’, down *purely* the effect above, are quite uncommon. The real problem is that too many people diagnose ‘rising damp’ at the drop of a hat, and don’t take the trouble look for the obvious (and more likely) causes, i.e. do what susiecam suggests.
The age of Gulp's property suggests that he probably has a slate damp course and it is very unusual for this to fail hence looking for the cause of the damp remains the most sensible first approach. Very interesting, if somewhat scholarly, article on this subject attached.
Surely Gulp’s best course of action is to make a proper diagnosis of the problem and identify for the source of the moisture, i.e. to look for defective surface drainage, leaking pipes, condensation problems, defective pointing, flaky impermeable external paint... This is much better than pumping in silicone on a ‘just in case’ basis. If the moisture really is rising up through several levels of brickwork then there must be a small lake under the house – the fix would be to drain it and re-establish the cross ventilation.
Originally posted by phugoid: Surely Gulp’s best course of action is to make a proper diagnosis of the problem and identify for the source of the moisture, i.e. to look for defective surface drainage, leaking pipes, condensation problems, defective pointing, flaky impermeable external paint... This is much better than pumping in silicone on a ‘just in case’ basis. If the moisture really is rising up through several levels of brickwork then there must be a small lake under the house – the fix would be to drain it and re-establish the cross ventilation.
You don't need a lake, just general dampness of soil. If he can fix it , then fine.
But don't move in and think it'll be alright as it probably won't.
Have you ever dug up an old fence post? Have you seen how wet the concrete and post really is in the soil?
This is the damp that gets drawn up through the bricks.
If you've ever lived in a damp house you will know what I mean.
And how do the people who inject DPC's make a living? Oh that's right, by telling you you've got damp, and need a new DPC injected, and they'll also spray all your woodwork with god knows what chemicals as well whilst they are at it no doubt.
I had a condition on a mortgage to sort out damp that showed up in a survey. Looked in the yellow pages and got three different firms in, and lo and behold, every one of them recomended a new damp course injection, new plaster up to one meter high, and spraying of all the timber in the house. Not one of them came up with the reason why there was any damp, or any other recomendations as to how any damp could be reduced or eliminated. I was sure that they were wrong, but needed something in writing from someone who knew what they were talking about, in case I had any come backs on the mortgage. I was sure that it was just high ground levels in one place, so I got a survey by a firm of environmental engineers, who aren't trying to sell you any treatment. Their report, (about forty pages worth) told me everything I needed to know, confirmed the two places I had a small amount of rot in timbers close to walls with high ground levels, and gave me the recommended course of action, (it ain't any use spraying timbers that have rotted, you need to cut them out and replace them.) And it also stated, in plain clear English, that I did not need any injected damp course, or timber spraying treatment.
The report cost around £1600, all the treatments were around £3000. My advice, talk to someone who knows how buildings are constructed, and how they are designed to work, and who ISN'T trying to sell you a course of work that may not be required, rather than some a*$ewipe who used to sell secondhand cars last year, timeshares the year before, and will be selling UPVC windows, gutters and facias next year when he can't work out how to change the batteries in his dampmeter. I'm sure there are some very nice and sincere people who know what they are doing in the damp treatment and timber presevation industry, but I've not come across them yet.
Get hold of Jeff Howell's book, "How To Look After Your Property", very clear, plain English.
You paid £1600 for someone to point out that the earth was high in a couple of places??
How many months did they spend on site to work out that little gem?
You can do your own DIY dampcourse by drilling into the lime mortar layer and squirting Thompsons No-more Damp into the holes. It's not as good as the injected job - but it still works.
As far as replacing joists goes - it's a 2 hour job and costs about 20 quid.
Now let me run this one past you.
You have a damp wall.
You call out the enviromental engineer (and pay him for about 6 weeks work).
He wanders around and can't see anything - but the wall is damp.
He thinks you have a cracked drain 6 feet below the concrete driveway.
How does he sort it?
How do you sort it?
Dig up the entire yard to find the drain?
Follow it along until you find the crack?
What if it wasn't the drain, it was just moisture in the soil?
You'd have paid out £1600 quid for one blokes opinion, he would have you dig up all your yard for nothing? Wall still wet, yard a complete mess.
It just isn't worth it.
A quick inject job for about £300 - and it matters not where the damp is coming from.
Erm, Lee33, not involved in the damp proofing industry are you by any chance? Blind faith like that has to be born of vested interest. So in your book if the question contains the word 'damp' the answer is always going to be 'injected chemical damp proof course'? So whether the cause of the damp is actually a fractured drain or concrete breaching the damp course or a leaking donwpipe it's better to lob a chemical barrier between you and the problem rather than solve the problem? Me no understand.
lee33 - "You paid £1600 for someone to point out that the earth was high in a couple of places??
No lee, try reading it again. I paid £1600 to a firm that would tell the banks surveyor he was talking rubbish, and would go to court for no extra cost. I had a condition on the mortgage that the banks surveyor had spotted damp in several places, and that I had to get it sorted out. I knew it was high ground levels, but i'm up against an RICS surveyor. I haven't got any letters after my name. Damp treatment firms all told me it needed a new DPC injecting (well, they would, wouldn't they?). Doing the work yourself doesn't get the all important guarantees that the bank wanted to see from a "reputable" firm, does it? I didn't want to get the environmental engineers in, I'd rather have kept the money to myself, but the bank's surveyor has put the condition on tha
