Buying house, lots of damp on survey

[jamestyler]

Hi

I'm looking to buy a stone built house, circa early 1800s. It's quite large, 2500sqft, 4 beds.

We've had a damp survey from an independent surveyor, who has no interest in selling us services. We picked him as he has a good repulation, after some concerns raised on building survey. Rest of building survey was pretty good (ie no structural, roof issues, etc)

The report has raised that =:

The right hand gable end wall is showing high moisture readings from ground level to top of 1st floor.
The timber that could be measured abutting this wall showing 40%+ moisture reading. Couldn't measure floorboards/joists.
Downstairs on that same wall, a wooden bean going from floor to ceiling is showing 27% moisture readings.
Front and rear elevations can't be measured, due to plasterboard on wall (no visible damp)
However, the dividing walls going at 90 degrees to front elevation show high moisture closest to the front wall
Rising damp, no DPC is most of building due to age
Internal plasterboard has no visible signs of damage, but we can't access behind


Surveyor has recommended repoint, which will be very expensive as it's random stone, needs cement patchwork manually raking out and replacing with lime), then a silane siloxane water repellant added.

Due to the drylining on most walls, recommended we access behind this to see how it's looking. If attached with timber battons, these would be likely damp, and would need plasterboard/batons removing, cavity drainage membrane fitting to wall, then replasterboarding over the top to isolate the wall from the plasterboard.


So...

I'm OK with the repointing if we can agree a reduction in price to cover this, but the big unknown is the plasterboard. If we have to strip, add a membrane and replaster, that's £1000s of cost, and a huge amount of disruption. It doesn't sound particular sympathetic to an old building and I'm not sure I like the idea of living in a tupperwear box.

As there's no visible signs of damp (or smell) downstairs (there is upstairs near gable end), then I'm hoping there isn't an issue, but it's such an unknown/risk.

Any advice from people who have experienced similar problems would be much appreciated as it's quite difficult to interpret all these different reports and opinions and I don't want to jump into a purchase ignorant and end up paying out huge bills.

I also have a mould allergy and a 12 month year old daughter, so our health comes first with all this.

Many thanks for your advice

 

[Zebra]

Hmmm, a difficult one to advise on, since as you say, it's a bit of an unknown quantity. Do you know when those works were done and who by? I mean was it a "tarting up" to sell it, or a genuine effort at sympathetic restoration?
If you are willing to take it on come what may, even if there's a can of worms behind the plasterboard, and are willing to live in a building site for a while, then I'd say do it, but with a small child and a mould allergy, I wonder whether that's where you're at.

 

[Flyfisher]

Have you been able to discuss things face to face with the surveyor or are you just working from the report? Surveyors are often more forthcoming in discussions than they are prepared to be 'on the record'.

Regarding the damp gable end wall, I would want to ask the surveyor why he thinks it is damp rather than just get a report saying it's damp. If the damp is very bad so high up the wall I'd want to look very carefully at what's happening with the roof. Is there a chimney with poor flashing, for example, that could be allowing water into the top of the wall? I mention the gable wall specifically as it seems to be in a rather different condition to the other walls, which in my mind begs the question 'why?'.

Repointing has been mentioned but has it been explained why he thinks this will (might) help? Whatever the reasoning, repointing with lime for breathability then treating with a water proofing agent sounds a little odd, though I'm probably not understanding things fully.

As to whether to take it on, that's something only you can really answer. I think it unlikely that the problems you've described could not be fixed but it's always an estimate about how long and how much it will take and a big part of the equation is how much risk and disruption you are willing to take. I tend to agree with Zebra about the allergy and baby issues; they must surely be an important factor when contemplating living on a 'building site' for a few years . . . . something that many of us here have done, especially the DIYers for whom timescales generally seem to be longer than initially anticipated!

 

[steveb]

regarding air quality, I now swear by MHRV (or MVHR?) systems that run continually extract air from the building and replace it with fresh warmed air.

However they are not cheap to fit and not very suited to retrofit - however you get a continual flow of fresh air and it in effect draws out humidity so the overall result in my eyes is worth paying for. You do need to budget several thousand to get it installed though, assuming you can run ducts in the required places.

-Steve

 

[MatthewC]

Hi James

Zebra and Flyfisher make some very good comments above. It sounds as though someone (the current owner?) has done a bunch of things that most of us would probably not do on such a house. A great example is the dry-lining - was it done to cover dampness or just because they couldn't be bothered to plaster? I would support FF's point about the roof and flashings, and what about the gutters etc? You shouldn't have dampness at that height unless there is a logical cause.

Your surveyor might not be in the pay of DPC companies but has he got experience of old buildings? If the surveyor has recommended a "silane siloxane water repellant" after re-pointing with lime, then he doesn't understand why you should use lime!

Also, fitting a cavity drainage membrane to the wall is only addressing the symptom of any dampness: it will not address the actual cause and, you are right, it is not "particularly sympathetic to an old building" so is not a solution often implemented by us here!

Whatever you might think about estimates for doing any work on an old house, the one thing that most of us agree on is that in most cases it costs more and takes longer than you expect, as there will be surprises! If living in a building site is not for you in your circumstances, then don't do it.

Best wishes

Matthew

 

[88v8]

Mould loves damp.
Our house has no visible damp on walls, but with no dpm and no dpc, the rh currently is 70%.
We have black patches in various areas where the air is dead, and I don't doubt that the atmosphere is full of spores.

Visit again, take a hytgrometer or two with you.
https://www.amazon.co.uk/ThermoPro-Digital-Thermo-hygrometer-Temperature-Humidity/dp/B01J7OH72S/ref=sr_1_1/262-6750580-5659933?ie=UTF8&qid=1505462638&sr=8-1&keywords=hygrometers
then you'll know.

Sorry, but I'd look for a newer house, Victorian onwards, with a suspended floor and a dpc. Aim for a summer rh of 50% or better. In winter, our rh tends to fall because the heating dries the air, but we never go below 45%. It's the way it is.

Ivor

 

[DavidB]

Hi James

I once had to create an inspection hole in plasterboard to allow for a follow up from a survey in a house I was selling. It was a pain and I thought it was unnecessary at first - but I wanted to sell so I did it. I think you could ask to inspect behind the plaster - the current owner won't be the first or the last who will have to do this...

Incidentally my inspection hole was nothing to do with damp, but to prove a suitable RSJ was holding up an arch. It turned out that there wasn't - but the buyer bought the house anyway - so I was wrong to think it was unnecessary, but it all worked out fine.
One view is that it is implicit in the report you paid for that the presence off cement pointing is trapping moisture behind the stone work... I'd ask the surveyor to be a little more explicit. He might say "I dunno what's causing it - you'll need to do some investigation..."

In my own damp house I have found timber batons holding plasterboard to be in perfectly good condition. Whereas I find small areas where the plaster board has blown and become powdery and loose on the surface.

Good luck!

 

[Bevmarley]

Same here surveyor raised damp issues in upstairs bedroom and a few other places . Ours is mainly caused by cement pointing outside and unbreathable plaster inside. We are tackling the issues ourselves but we don't have small children and are retired. Whether we would have taken it on in your position I doubt. It has cost a lot more than we anticipated and is a very dusty job. Think long and hard as there are days when I think we must be mad. Bye the way we cannot afford to pay anyone so are doing it ourselves.

 

[jamestyler]

Thanks for the replies/advice

We revisited the property this week. We also looked at some of the plans from the original conversion in 1976 (was again renovated in 2005 with new roof, etc)

It seems that for half of the property, there is an inner brick leaf, which has then been plastered. This is good! This was from the original conversion.

The other half (done in 2005) has the outer wall, then plastic sheeting, then kingspan insulation and foil backed plasterboard. We accessed a hole in the wall where the TV aeriel comes through - it was at ground level and bone dry. Can't tell if it's timber or metal batons, but with the plastic layer in there it all seems dry so not a big concern.

So that looks rather good, and seems the surveyor's doom and gloom about rotten batons was just being over cautious.

Regarding the damp on the gable/external walls, we checked out the pointing.... :shock:

Along the external ground level against the gable end, there is a concrete slab. There used to be a lean-to there, but it was knocked down. The concrete floor outside butts right up against the stonework (higher than internal ground level), and lets rainwater sit there. There's moss and holes going in between the stonework where the rain has been sat against it for a while. Further up the wall, there are holes, and some cement re-pointing. It's quite a mess. Internal to this, on the same wall, it's been painted. I was hoping it was lime, but looks like a shiny white paint.

So the combination of poor pointing, gaps in pointing, higher ground level, then an internal layer of paint, seems to me to be the cause here.

There was also an overflowing gutter on the front of the property, and after heavy (heavy) rain that morning, when we visited, the room near this smelt a bit musty. The pointing on the wall near this had degraded too.

Seems the current owners haven't really kept up with the maintenance.

Our plan is to get the house re-pointed in Lime, add a channel outside near the gable end with a french drain, then somehow remove the paint from the internal wall and lime plaster it (or just leave bare for now). We're going to be asking for a reduction in price to cover some of this.

So far we've had a quote for repointing at £25k!! :shock: So will be getting some more..

 

[88v8]

Compared to many, you are far ahead on the knowledge curve.

If you like to mention the locale, someone may be able to recommend.

Ivor

 

[Bevmarley]

Yes a specialist in lime is expensive and usually very busy hence why we are doing it ourselves.

 

[Anonymous]

Hi and welcome.... as per the good advice from the other members all good.
I should say that RH reading of 40% isn't high for timber or anything else for that matter.

and to labour a point THERE IS NO SUCH THING AS RISING DAMP... it doesn't exist see https://www.heritage-house.org/ and watch some of Pete Wards interesting videos.
If a surveyor and there are oh so many is telling you there's a rising damp problem and saying there's a problem with damp in timber at 40% RH then he's not qualified to call himself a surveyor.

Surveyor's are I'm afraid in my experience for the most part either utterly incompetent or conning us all out of hundreds / thousands of pounds.
I have to question the cost of a full structural survey / homebuyers report (whatever they're called now) as they're often not worth the paper their printed on.
Buy hey you / we pay your money anyway regardless. Tbh I'd want a surveyor to walk me round the property and discuss the survey not just present me with an unchallengable report which I HAVE to pay for.

It's impossible to argue with your mortgage company when a surveyor says you have damp or woodworm or some other terrible thing, they have RICS or BRICS at the end of their names so they must know what they're talking about... unfortunately it's not the case. You've determined using your hands that there's no damp so that should be good enough.
There's no need to put holes in your plaster with a meter designed to measure water content in wood as this just measures conductivity which is caused by a lot more things than just water...

Damp smells, if you can smell it then it's there... if you can feel it then it's there, if you can't then it isn't. Look at rainwater goods / water leaks, ventilation and ground levels (the last two are the biggest causes of damp). If you have plaster board / DPC / membranes these need to be removed to let the building breath etc etc (all of which I've found in my house) then that's the cause.... We are all as good as surveyors when it comes to detecting damp / damp problems, they should really concentrate on structural things that they should be qualified to look at rather than things they clearly aren't.

My own FSS specified on 16 different pages that I should basically "get someone (a specialist) to investigate this problem" luckily I'd been to Peter Wards website and was clued up. It basically cost me £5,000 as the building society refused to loan me the full amount unless I had certificates from chemical damp proofers... I tell you it's all a racket and I'm pretty convinced they're all in it together. (cue now a string of people defending surveyors etc..) flame on !

All the best with your project.

Paul.

 

[Kearn]

I tell you it's all a racket and I'm pretty convinced they're all in it together. (cue now a string of people defending surveyors etc..) flame on !

It is the unfortunate truth in the majority of cases it would appear. Certainly my experience through various 'surveys' required by mortgage companies... may be able to spot wetness, but highly unlikely to understand the actual cause, therefore certainly can't provide a solution. As stated already above, the reality is with damp in an old house is that it comes from moisture firstly getting in (ground levels, inadequate drainage, broken rainwater goods, other leaks, damaged or partially applied modern materials...) and secondly not being able to get out again (plastic paint, concrete, gypsum render, tanking, plastic...). Thankfully the equation is relatively simple, and so is fixing it - however, it can often be time consuming, disruptive, messy and expensive... so the Q is whether it is something to take on or not. My experience so far is that 80% of the job is progressively destructive and you wonder why you started, until suddenly you've finished and you know it was worth it!

Removing plastic paint, gypsum render, concrete etc is a really satisfying process - you smell the damp immediately, but the reduction in smell and colouration on damp timber, even during the first few days is rewarding...

To sum up the 10 minute visit rent-a-surveyor type, we recently remortgaged (late 16thC timber frame cottage with external lime plastered panels plus early 18thC Georgian addition, with 3 beds) - the surveyor happily ticked the box for the required valuation amount, which was the objective from our side, but I found it interesting looking at his check sheet report, that he had listed the house as a 2 bed brick build from the last century?! You must be able to buy those suffix letters online...

Good luck!

 

[Flyfisher]

I should say that RH reading of 40% isn't high for timber or anything else for that matter.

Indeed. It's actually towards the dry end of that required for a comfortable living environment.

For humans relative humidity below 25% feels uncomfortable dry. Relative humidity above 60% feels uncomfortable wet. Human comfort requires the relative humidity to be in the range 25 - 60% RH.
http://www.engineeringtoolbox.com/relative-humidity-d_895.html

The ideal relative humidity in a British home is around 50 to 55 per cent.
http://www.telegraph.co.uk/finance/property/advice/9614700/What-is-the-recommended-humidity-for-a-home.html

Tbh I'd want a surveyor to walk me round the property and discuss the survey not just present me with an unchallengable report which I HAVE to pay for.

Agreed and the two times I've paid for a full structural survey they've been perfectly willing to do just that. The opportunity for direct questions and answers turned out to be more valuable than the final report really because they have to cover themselves for any liability in writing but seem willing to give far more information and opinion in a conversation.

 

[Flyfisher]

To sum up the 10 minute visit rent-a-surveyor type, we recently remortgaged (late 16thC timber frame cottage with external lime plastered panels plus early 18thC Georgian addition, with 3 beds) - the surveyor happily ticked the box for the required valuation amount, which was the objective from our side, but I found it interesting looking at his check sheet report, that he had listed the house as a 2 bed brick build from the last century?! You must be able to buy those suffix letters online...

To be fair, that sounds more like a 'valuation survey' where the vendor is really only interested in how easy it would be to get their money back in cases of default.

We once re-mortgaged a house for a loan of around 30% its market value. The lender required a survey of course but frankly the surveyor was wasting his time even getting out of his car as the plot alone would have probably covered the loan. I don't think he was in the house for more than 10 minutes and I don't remember him even looking in the attic! :lol:

 

[Kearn]

To be fair, that sounds more like a 'valuation survey' where the vendor is really only interested in how easy it would be to get their money back in cases of default.

yep, the last survey was just that, as stated a necessary evil - still surprises me though that someone allegedly qualified can't tell whether a house is built from trees or bricks or count the number of rooms with beds in...!!

it is fair advice for any one having a survey done, to a) find someone experienced in old buildings who can spend a day walking you around and discussing - it costs, but not much more than a 'full survey' from a clipboard monkey, and if not then b) at least speak to the theoretical surveyor, as the report is an exercise in arse covering - so many of the potential issues aren't really concerning but some of the areas you will find out a true opinion when it isn't documented...

 

[Zebra]

and to labour a point THERE IS NO SUCH THING AS RISING DAMP... it doesn't exist see https://www.heritage-house.org/

Well I had it. http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=13077
Cured by inserting physical damp proof course.

 

[Anonymous]

Hi Sorry Zebra,

but without even seeing your property I can tell you, you didn't have rising damp (coz it doesn't exist) and you definitely didn't need a damp proof course.
As per the discussion with my wife this very afternoon... Wife: "I just can't believe that all these surveyors are wrong, if it's wrong then why hasn't it been corrected", Me: "If I paid you to say that rising damp is definitely a problem, or that you wouldn't pass your RICS exams unless you said it did, would you still say it didn't exist?"....

I'm paraphrasing heritage home / Peter Ward: The only two countries in the world where they use a damp proof course, UK & Australia.... what about all those houses in Holland built below the water line.....

Sorry but just because you paid out money to have work done doesn't mean I'm wrong and you're right. There are two types of damp, condensation and penetrating.
My wife was collared by a neighbours son this weekend who's a surveyor and couldn't believe it when he suggested we had two holes per brick drilled and had them filled with silicone, she said we couldn't do that because it would be illegal and that the only problem we have with damp is because one of the rainwater pipes leaks when it rains and the ground levels are 4" higher than the inside floor...

 

[Zebra]

Hi, I'm sorry, but I did. The circumstances might have been unusual, very old porous bricks, but cutting in the dpc (I'm not promoting injected ones) definitely did cure it.
Why do you say that I think I'm right because I paid a lot of money? I didn't pay any money.

 

[stuart45]

I did work as a bricklayer years ago in Belgium and Germany and can remember them putting a DPC in the walls back then, although it wasn't bedded in as we do it here.
Rising damp is also talked about as wicking of moisture in the USA.
http://www.emerisda.eu/wp-content/uploads/2014/07/D-2_1.pdf
In this article you can read about the methods used in different countries for a DPC.
This does not really prove it exists, but it's wrong to suggest that it's only here and Australia that use a DPC.