BigBear - loved your postings : impassioned, articulate and amusing. Totally understand where you're coming from. I would rather invest money in getting it right than invest money in consumately waterproofing my house. I'm still smarting from being a naive first time buyer being told that I HAD to do certain things to get my mortgage, things I learned subsequently were not only unnecessary but which may have caused damage to the fabric of my building (C.1850). Gutted by this I determined to research & learn about the causes of damp and the detrimental effect of certain 'remedies' on old buildings so that I would never make the same mistake again.

Lee33 - beginning to understand why you're so forceful about chemical intervention - if your house was as bad as you describe, however, it begs the question why you bought it in the first place given that it appears to have been constructed from recycled Bounty kitchen rolls. As far as drains are concerned, it isn't such a big deal to have them surveyed - I just have and discovered a fracture which explains a lot. Cost me £850 to put right, but at least I haven't got raw sewage leaking into my garden.

Gulp: Light the blue touch paper and stand well back! You sound like a sensible person and the reason you sought advice in the first place was to avoid pitching in to the obvious cheap and 'easy' fix. Live with it a while and see where it gets you. Still got a problem? Call in an independent specialist (if you can find one, and if his name is Lee I'd be a tad worried - sorry Lee33, no offence, truly! )

lee33 - "The house literally sits in water."

Wow, that's wet. Now come on Lee, own up, you've bought a house boat, haven't you?

"A drain survey won't reveal a leak as it isn't visible - so what do you do? Dig up the whole lot? And what if it wasn't the fault at all?"

Well, maybe it's just me, but if, after all other avenues above ground have been explored, and the only thing it could be would be either an underground pipe leaking, either drainage or supply, or ground water, I'd want it fixed, if it were my own house that I was going to live in. I can understand that if someone was doing house renovation as a living, and the cost of digging up and repairing a main was coming off the bottom line, then the quick fix of curing the symptom but not the cause is what some people would do, flog it and move on. And if you dug up everything and couldn't find any leaks, then you say "oh dear, what a pity, what a shame, never mind." And then question your reasoning for buying a house in a swamp.

"As I said, 20 quid will get you a couple of joists and i really thought that anyone could fit them. It's not exactly difficult."

No, what you said was "As far as replacing joists goes - it's a 2 hour job and costs about 20 quid." So, the job has gone from £20 to just the joists costing £20. You haven't explained how you can remove an original Victorian floor, replace the rotten joists in a bay window, and replace the floorboards, without damaging them, in two hours yet, have you? (And I haven't mentioned about removing skirting boards at one end of the room so you can get the boards up). Yes, I can and did do it myself, but I would not for one minute think that "anyone can fit them."

"In your position I would have had an 'injection only' from a 'reputable' company."

"The cost is around £300 to £400."

"You do all the donkey work yourself."

I haven't made this clear, have I? Injection only isn't an option, the "reputable" firms would only guarantee their work if they did the plastering, and also the house had to have all the timber sprayed as well, hence the £3k. So, the choice is £3k, or £1600 for the report. And things that cost £300 or £400 to you can cost a hell of a lot more in other parts of the country.

"I trust you can plaster?"

Oh yeah, like can't everyone? Where you come from everyone can replace floor joists and plaster too. What a muti-skilled place you live. I can't plaster, not to the standards I'd want, my four years C&G was in another trade. But I've met plenty of people who think they can, usually when I'm writing their snagging lists.

"What other bumf did your report contain? All the usual jargon-speak to baffle the unwary?"

"So how long WAS he on site for?"

My report contained all the information I needed to to tell the bank's surveyor he was wrong, and have that condition on my mortgage lifted. Told me which timbers needed replacing, not just visable but hidden areas as well, samples taken using a small drill and taken back to the lab for tests, true levels of damp in brickwork again taken from core samples, not just by some muppet sticking a damp meter on your wall paper. Yes it was expensive, more than I wanted to pay, but it still saved me spending £3k on work that wasn't needed. Two blokes for two days, and they had a few degrees between them. But then they are a major company in their field, major companies go to them for advice, they also do a lot of heratige work. You're not paying just for their work, you're paying for their indemnified opion, if it all goes legal. Still, I'll never need to use them again, because Lee is going to tell us all about the guy who charges £53 a day.

"My house in in the Trent valley. My foundations go below the water table. It's a Victorian house, so you should know the type of bricks I'm talking about. How would your 'specialist' get by that one? The house literally sits in water."

I haven't a clue what bricks your house is made from, never said I did. Nor do I care.

I think any "specialist" would actually want to come and see the site before telling people how to solve their problems on the net. Everyone here has stated the obvious course of action, check ground levels, blocked air bricks, breeches of damp course, uses of wrong materials, paint etc, faulty rainwater goods. Some of us, me included, have warned to be cautious with recomendations of works required by damp companies. And your course of action is to use an injected DPC. Lee, I think the only thing you and I are going to agree on is that we disagree. Like you say, you've got your opinion, we've got ours.

"I buy and renovate property as part of my living.
Renovating is what I do all day."

There are some other people on this board with more than just a passing knowledge of the construction industry, you know.

quote:

Originally posted by BigBear:


There are some other people on this board with more than just a passing knowledge of the construction industry, you know.

Then let's hear form them.

1600 quid is an extortionate amount. A professional body should have a scale of fees - not work out how much they are saving you.

Does your doctor say "This will save your life - now give me your house"?

As far as floors and joists go - anyone can do it. It's hardly something to crow about.

Now what happens in ten years time when you sell your house? If the prospective purchaser cannot get a mortgage due to damp?

It's no good arguing that a couple of men with letters (wow) after their name spent 2 days looking at a bit of soil in your garden is it? What on earth were they doing for 16 hours? How many hours can you look at a bit of earth for? Sounds like a 10 minute job to me. I'd have told them where to go.

They'll say "It may have been dry then - but it's damp now" - we want a DPC.

Sale drops through because you want to argue the toss.

BTW, Suziecam (funny name? Mind boggles), all bricks apart from engineering bricks are porus. If you had a Victorian house you would know that.


lee

Well, I never imagined this thread would make me laugh out loud, but it has! Thank you for the contributions so far....

I'm heading off to look for books by Jeff Howells shortly - I have become a rising damp obsessive

(Probably best I don't tell Lee my plans for the woodworm, I think!)

there's a book Water in England by the historian Dorothy Hartley in which she points out that up to Victorian times the vast majority of houses were built by the people who were going to live in them. And that contemporary complaints about damp, shoddy building etc apply to housaes bulk-built for workers by developers, eg factory or land-owners.

She asks: did people really, for hundreds of years, deliberately choose to live in damp unhealthy conditions? Or did they know things about looking after these buildings that we have lost.

Lee, please tell us how much you would pay for a full structural survey on a three bed Victorian semi in your part of the world then. And who is this guy you know who charges £53 a day? You've insinuated that £1600 is six weeks work, which works out at £53 a day. The people I had do my survey did set out the fees before I engaged them, I did the maths myself about what was saved. (GOSH ain't I clever!) I'm fully aware it's alot of money, it came out of my wallet. But my choices were get the survey done, or pay nearly twice as much for works not needed to get certificates and guarentees.

And I'm not "crowing" about being able to replace floor joists. I'm the one saying that in fact, not "anyone" can do it. I've seen quite alot of work that people "think" they know how to do in my twenty something years on site. But then we all STILL await your explaination on how you can take up a floor in a 14'x10' room, replace the rotten joist section in a bay window, and replace the floorboards in two hours, without damage. Please tell us all. Do you tuck your cape in your underpants when you work, in case it catches in your tools?, 'cos if you can do that in two hours you are truley superhuman. If you are going to comment on how long jobs take and how much they cost, then please let us in on your secret. Would it make any difference to you if the floorboards were made of kryptonite, or does that not effect your super human powers?

In ten years time if I was selling and damp showed up on a buyers survey, well to me that would be even more reason to not get some muppet firm in to inject a DPC, I'm damned if I'd want all the hassle and mess just before I was moving. I'd much rather go down my route of proving what was actually there. It's exactly the same as when I bought, if a bank wanted to see guarantees and certificates that would cost £3k, or have an unobtrusive survey done at £1600 that said the work didn't need doing, to me, it's a no brainer. But then unlike you, I can't get this bloke you know doing full structural surveys at £53 a day. Oh, and of course it's only a ten minute job to do a full structural survey in your world isn't it, so, by those standards it'll cost you a grand total of £1.10. Is that with or without vat?

Lee ,you're doing a good job of not answering the questions put to you by me on how you come up with your times and costs for the works discussed. I wonder why you don't answer?

I don't NEED a structural survey on properties I buy. Neither do I NEED a bank loan.

I am quite capable of repairing any part (or all) of a house.

Whether it be joinery or brickwork or plumbing or electrics - I can do them all.

As far as repairing a floor goes, you simply remove the skirting, lift the boards cut out the old joist, add a couple of joist hangers, replace the joist and nail the boards back down. If you can't do that in 2 hours - what can you do?

Now you tell me why it takes 2 engineers 32 man hours to work out what YOU worked out in 32 seconds.

When you come to sell and the damp meter gives an adverse reading - where does that leave you?

Will you recommend that the prospective buyer pay someone for 32 man hours to work out what you can work out in 32 seconds? It'll only cost £1600!

Just what were they doing for 32 man hours?

How many times can you look at a mound of earth and say "OOH Justin! That's a little bit high" "Yes Wayne I quite agree - let's have another look at it".

For heaven's sake!.


lee

I too am intrigued by the idea that this forum has become a portal to another universe, parallel to our own, but where time runs at a different rate, money is infinitely elastic, and the laws of physics allow the construction of perpetual motion pumps using nothing more advanced than a few Victorian clay bricks .

But back on planet Earth, this Historic Building FactSheet: Control of Damp, Diagnosis and Inspection, published by the MoD, sets out some of the facts and gives good practical advice. Contains a section on rising damp, dpcs, and French drains.

I too have enjoyed this thread.

I side on the against-Lee side of the fence. He may well be able to do it in 2 hours, but for most of us my double-it-and-double-it-again rules applies - so 8 hours for a job like that. We have never done it before and have to learn every time.

I avoided a survey on my current house, a) because I had some experience of similar aged houses, and b) because a damp allegation would trapped me into stupid work and cost. And I have not regretted it either.

Take a peek at this

Playing devil's advocate here....could someone...maybe Lee......PLEASE tell me how effective an injected DPC really is?.........I presume you cannot be 100% sure that the material injected has completely saturated the wall in order to stop "rising damp"?

If you live in the trent valley, believe me, damp does exist. It was so bad that the wallpaper was falling off and the bricks three shades darker. The plaster was completely disintegrating and full of white crystals. Every morning the window sills would have pools of water that even ran down onto the floor.
The houses in this area are actually standing on 30 feet of gravel (washed down from the Scottish mountains that once existed during the last ice age).

One thing I don't get, is if damp proofing isn't necessary - how does it cure what doesn't need curing?


lee

When the damp proofing silicone is pumped into the bricks you see the bricks start to sweat like beads of perspiration. The beads then form little rivulets that actually run down the bricks.

etc - your question is a good one. How can one liquid (the gunk) drive out the other (the water) from a saturated wall?

And how long will the proofing operate for? I have heard 10 years max. Many Victorian houses have stood, without the plaster falling off the wall or the timbers rotting, for 100 years.

My case rests.

Learn a little about chemistry, Simon.

Do you know that the WD in WD40 stand for Water Displacer?

Proper proofing lasts indefinitely.


lee

I think what is becoming clear is that certain parts of the country are prone to damp (low lying/clay soil etc) and others are not. I know that the chalky areas like Wiltshire are far dryer.

I still find it hard to believe that RICS surveyors have stipulated them for the past 30 years or so if all of their members have noticed they were pointless.

And I still think £1600 is silly money for 10 minutes work. Imagine if his solicitor charged him on the same scale. He'd hardly be sing his praises.

lee

i live in the trent valley.

my house was pretty much like lee described. (wallpaper hanging off, pools of water, water running down walls in places, etc etc) and had already been treated with a dpc!!! luckily as i didn't need to get a mortgage, i didn't have to go down the new dpc course. i just treated the causes. it's a bit like medicine: treat the disease, not the symptom (as lee used a medical analogy)

this thread has highlighted the reason i would never buy a 'renovated' property

lee33, I think there is truth in so me of what you say. However, nobody knows it all, and I have always found that if you listen to others you can learn, and often get a very different insight. I think the injected DPC is a good product, where appropriate, but you need to look at the big picture and often it IS a case of curing the symptom rather than the disease. I am always having to explain to people that their problem is not "damp", but condensation due to the fact that modern windows are draught-proof, and we don't ventilate enough. As a matter of interest, if you see black mould on walls, it's not "damp", it's purely down to water condensing on a cold unventilated surface, allowing fungal growth to take place . This is exacurbated if the heating isn't adequate, as the relative humidity is increased, which means there is more water to condense on any cold surface. I've gone off on a slight tangent here, but I think it demonstrates how there can be more to a subject than meets the eye. An independent surveyor, ( albeit £1600 ), is more than likely looking at the overall picture, has no product to sell, and is probably therefore giving sound advice.

There is an underlying problem here in that all he has done is put off today's problem until tomorrow.

His wall plaster will be filled with hygroscopic crystals. This means that they attract water from the air. When the next suveryor applies a damp meter - it'll go off the scale.

So what has the £1600 quid ten-minute-job really achieved? Someone at some time will have to install a DPC.

It's just not worth the risk of losing a future sale over.

Rising damp is a fact. It's the same principle that allows a sponge to soak up water.

Try it for yourself. Stand a brick in a bowl of water that is 1 inch deep. After 20 minutes take a damp reading on the top of the brick - it's full as a sponge.


lee

Lee - of course you are right - once you have identified the cause of the damp and cured that, you have to treat the damage caused by the damp.

But: what some of us are trying to tell you is that an awful lot of damp problems are labelled simply "rising damp" when they are nothing of the kind - like my broken drain cited some posts ago. Yes it was damp rising from wet ground, but the surveyor didn't bother to think, why a patch of very wet ground in an otherwise well-drained, chalk hillside site? My cottge is cob, so I couldn't have an injected damp course anyway, but had it been of brick or stone, I might have been suckered into paying a lot of money as opposed to a few quid for replacing a drain and downpipe.

The message is, You can't necessarily rely on experts even if they have RICS or whatever after their name. Use your own eyes.

Lee33 - I would look at the ‘engineering problem’ in this way (misdiagnosis by the bank that triggers a call for unnecessary work is an altogether different problem) - apologies for the long post.

Clearly capillary action *will* draw water through the bricks, from a source at ground level, up to a height where the weight of the water column is balanced by the supporting surface tension acting around the open perimeter of those pores at the top of the column. A small amount of moisture may climb above this, through the very fine pore structure, but this moisture would likely not form a continuous connected path to the bottom, but rather form a series of very small isolated ‘islands ’of moisture that can evaporate easily with proper ventilation. In other words, there would appear to be an upper bound on the height that moisture can be drawn up through the bricks.

A quick ‘back of the envelope’ calculation gives a height of about 4*sigma/(rho*g*d), where the surface tension sigma=0.07N/m^2, water density rho=1000 kg/m^3, gravity g=9.81m/s^2, and pore size (very rough guess) d=200microns, i.e. about 15cm, but I accept that the precise value will depend on the particular pore structure of the bricks used. However, Victorian clay bricks tended to have larger pores to give better thermal insulation properties, and the estimate shows that larger pores would draw up a shorter column. Other factors influencing the height would be the degree of ventilation (or, equivalently, relative humidity and temperature) and the degree of saturation of the ground.

Older buildings are often designed to deal with the problem of rising damp by the simple method of keeping those parts of the building fabric that might be susceptible to damp, and any decorative finishes, at least 15cm (or more, safety margin) above the external ground level or sources of moisture. This works fine, as SimonTL points out, but over the years the ground levels can change, drainage can unknowingly be diverted, pipes can leak, ventilation can be blocked, vertical surfaces can be covered with impermeable paint, concrete floors installed, and so on, so that the design is prevented from working properly. Obviously the ‘repair’ is to remove these (more recently added) faults.

The modern system does not rely on vertical separation of the fabric and ground, but aims to prevent moisture movement by embedding an impermeable barrier within the brickwork. But this design, in its modern form, evolved by adaptation of the earlier practice, and at each time houses were considered to have been build properly and would have functioned correctly within the scope of their (at the time) design.

The dpc began to be introduced from (maybe) around 1850, with a barrier made from lead, stoneware, slate, or asphalt. By 1890, the practice was quite widespread, and by 1900 almost all new houses incorporated a dpc. And after around 1870 the floor joists would be installed above the ground, and the space below ventilated with perforated ‘air’ bricks, and in later houses this would be combined with a dpc.

These are just different ways of achieving the same result, but (in my view) the system should be repaired in a way that is in sympathy with its original design. Adding a dpc to a house that never had one should be done only as a last resort.

I should perhaps have said from the outset that the house in question does have a slate dpc in place. The surveyor described it as having failed. Concrete floors in the hallway and kitchen mayhave been laid too high - but I don't think so.

I am increasingly of the view that all that's failed are the systems of water drainage and ventilation.

Fascinating thread though - thanks all.

Lee, sorry, I haven't made this clear. £1600 was for a full damp and timber decay survey of my house. The whole house. Not a mound of earth in my front garden. So not quite ten minutes work then. The banks surveyor had said the house was damp with evidence of wordworm in the timber in several places and the bank placed a condition on my mortgage to get the work carried out, and wanted to see guarantees and certificates. Damp companies had all quoted the works at £3k. That involved a new