Damp Proof course

[Joe Malone]

Guys, I think this argument needs to be sorted once and for all.
For those of you interested enough I'm more than happy to send you a copy of my dissertation, 'The Efficacy of DPC Injection'.

It will answer all your questions in relation to the incidence of rising damp, how to diagnose rising damp and how effective chemical dpc's are. It's around 12,000 words but is an interesting read, even if i do say so myself. Drop me an e-mail if you're interested in reading a copy and maybe we can end this controversy during the next discussion thread.

 

[davebelushi]

We have sorted it.
I'm right.

 

[Joe Malone]

No you haven't, there are still lots of unanswered questions so I'll answer them.

Re: Moisture in the air and it's affect on brickwork... It's important to understand the difference between capillary moisture content and hygroscopic moisture content. Masonry will eventually absorb moisture from the atmosphere and reach an equilibrium, this will be its normal hygroscopic moisture content though it won't give sufficient moisture at depth to support a rising damp complex. Condensation problems will only give high surface moisture readings. You first establish a base line by testing in a known dry area for moisture at depth, this gives you the hygroscopic moisture content (HMC). You then take samples from a known wet area to establish the capillary moisture content, this is any moisture wicked into the brickwork from plumbing leaks, penetrating or rising damp. You then subtract the HMC from the CMC to give you the total moisture content (TMC). This is the important figure!

Re: Salts analysis... Nitrates can only be leached from the ground but chlorides and suphates are not really important. Chlorides can be present in tap water and sulphates are naturally present in plaster. Presence of nitrates in itself does not guarantee an 'active' rising damp problem. This information should be used in conjunction with evidence of moisture at depth in the masonry along with an appropriate damp profile. When you have confirmed all three conditions are present only then can you give a definitive and accurate diagnosis for rising damp. Even so, the evidence is that it's unlikely to be 'true' rising damp; it's more likely caused by bridging of the dpc in which case remove the bridge! Chemical dpc injection is not a cure, it's a management solution.

 

[anobium]

Joe Malone, no offence , but what makes you think you have come up with something new.
I think you will find that the BRE beat you to it about 35 years ago, along with many others.

 

[chessspy]

I'm with jbonding on this one,
rising damp is a wicked rumor, put about by damp proofing firms to make money and scare gullible people.
damp is almost always caused by condensation, injection is a last resort.
and 'surveyed'? By whom, the guy that want's to sell the gear more often than not...

 

[Joe Malone]

Anobium, I'm not with you, who mentioned coming up with something new? Unfortunately the BRE declined to answer questions relating to this thread.

Interestingly though the BRE tried to carry out a piece of research in the 70's with a major damp proofing contractor to assess the efficacy of their remedial work. They had to abandon the research due to the fact that they couldn't find enough properties with rising damp. I actually followed through and expanded on that research over a two year period and came up with answers that the BRE failed to get. Does this mean that rising damp doesn't exist... of course it doesn't and it would be foolish to say otherwise. It's just extremely rare and yet we have a whole industry that's grown from the supposition that rising damp is a common occurrence.

 

[Softus]

Does this mean that rising damp doesn't exist... of course it doesn't and it would be foolish to say otherwise.

Joe, your statement is mildly ambiguous.

I believe you meant that it's foolish to [seriously] claim that RD doesn't exist.

I'm looking forward to The Big Read.

 

[Joe Malone]

Sorry Softus, just a typo. Should have said, 'of course it does'. Thanks for pointing that out.

 

[Joe Malone]

Softus, still not got an e-mail address to send it?

 

[Softus]

Sorry Softus, just a typo. Should have said, 'of course it does'. Thanks for pointing that out.

No problem, but, to be picky, it wasn't a typo - the "of course it doesn't" referred to the "Does this mean...".

Regarding Email address, I've tried sending you an Instant Message, but there seems to be a software problem when the user name contains a space, like yours does. I'll tell Admin, but in the meantime you should be able to see my Email address in my profile.

 

[Shytalkz]

I'm all confoozed now: if, say a buried water supply pipe next to a wall leaks and the wall gets damp above floor level as result, are you saying that you do not class that as rising damp?

 

[Joe Malone]

I've looked and I can't see it. Maybe you could e-mail me, my e-mail address is definitely on my profile. I'll send it by return. And yes, you are being picky

 

[Joe Malone]

Shy, technically no. This is simply wall base damp though it would give exactly the same moisture profile as rising damp and have the same moisture transfer mechanism as rising damp.

By definition, rising damp must be moisture sourced from the ground which moves up the wall by the process of capillary action, the moisture will contain predominantly nitrate salts leached from the soil.

 

[Softus]

I'm all confoozed now: if, say a buried water supply pipe next to a wall leaks and the wall gets damp above floor level as result...

Is this something that you've seen happen?

If so, perhaps it should be called Rising Drench.

 

[Shytalkz]

And yes, you are being picky

Is Softus ever picky? Do ursus arctii use the area filled with trees as their toileting facility?