Rising damp does not exist

So i take it this is the findings :eek: does it exist or not? ive given up looking or asking, nobody can give the answer or proof so another decent post gone forever or :?:
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Not yet - I've been meaning to reply to DrSpock, but haven't the spare brain cells for the last fortnight.

It ain't over 'til the fat lady sings...
thank god for that, this cannot be pushed to the back, if it exists lets see and hear about it :evil:
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Hi All,

I'm a late contributor to this forum but nevertheless I'd like to clear up one or two issues. Does rising damp exist as a phenomena? Of course it does but it's far less common than the damp proofing industry would have you believe. I personally dont believe that DPC's fail, they are simply bridged or compromised in some other way. However you must remember that not all properties have a physical dpc fitted, legislation only forced their installation after 1875 but there are thousands of buildings that perform perfectly well without a physical DPC. This is because with adequate wall base ventilation the wall base reaches an equilibrium whereby the moisture evaporates as fast as it rises.
Jeff Howells tests at South Bank university where he tested for bricks in a tray of water for rising damp had one significant failure. The bricks were constructed obviously using new mortar; the point here is that the major moisture pathway for rising damp is the mortar joints. New mortar is impermeable to moisture but after years degrades and becomes porous. Unfortunately his tests were meaningless and were bound to cast doubt on rising damp as a phenomena!
Heres an interesting widely misunderstood point though... rising damp in brickwork occurs through the process of capillary action. Rising damp can also occur in solid concrete floors but the mechanism for moisture transport here is diffusion. Since the major moisture pathway for RD in walls is the mortar joints then actually the main moisture transport mechanism in walls is also diffusion. This is a radical rethink on the conventionally accepted wisdom that capillarity is the major cause of rising damp. My own view is that it's a combination of both diffusion and capillarity but rising damp definitely exists. On the rare occasions that I do come across rising damp i can treat the problem at source every time without resorting to dpc injection and this isn't as bold a statement as you might think.
Incidently I hope I'm well qualified to write on this subject; i recently wrote a dissertation entitled, 'The Efficacy of DPC Injection.'
I'm happy to take questions on this subject if anyone has any?

Joe Malone
Joe Malone, I think I love you. I feel like it's Christmas all over again.


What are the chances of getting a copy of your dissertation?
Unfortunately none til I've had it marked. Ask me again in June and I'll be happy to supply you with a copy.

Joe, out of interest which University have you been studying at? Good post by the way.


Thanks very much.

I studied at Northumbria but also had a year at Nottingham Trent, i moved on from there because it wasn't too good.
And what happened next?.... :?:

After 12 pages of debate and counter debate (and Giant Pandas?!) I think I might have found out why my plaster is saturated (interior breach of DPC by new plaster possibly), but I want to know about the dissertation, Joe 90's wet bricks etc etc
In many cases rising damp is wrongly diagnosed. In older buildings it certainly does exist through the factor of capillary rise. In newer buildings with damp course it should not occur unless the DPC is compromised.

However, capillary rising damp does occur in certain conditions and can be costly and detrimental to health. Bed bugs and the like flourish in damp and humid conditions.

Back to real rising damp - capillary rise i.e. water rising up through the capillaries in older buildings. To understand this we need to understand a little of Geophysics and the telluric fields that cover the surface of the earth (just search on Wikipedia). In a nutshell because of its physical and geological characteristics, the Earth, which rotates and is covered by north-south magnetic “force-lines”, generates a considerable amount of radiation. This radiation includes the presence of electromagnetic fields that give rise to electrical charges in water molecules and in the capillaries of the materials used to build walls.

These charges attract water to the drier capillaries at a higher level, until a balance is reached and a tide-mark of dampness forms.

All this aside many people get "conned" because of the wrong "diagnosis" of some of the existing rising damp firms and with most newish buildings the moisture is not rising damp!

Lol.. this old thread brought back some memories.. chuckled alot at the time.. and still brings a smile..

Most rising damp problems (where there is a dpc) are caused by people who breach the dpc, e.g. not digging out sufficiently for a concrete path - or some individuals who don't bother digging out at all and the concrete path ends up blocking up the air bricks and being higher than the dpc and rainwater/damp penetration becomes a problem, and if left unattended for a sufficient period of time can lead to 'dry rot' which gives the homeowner a real headache.


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