When I arrive at the majority of buildings, prior to starting a property survey, kind owners will often start by giving a walk-through of the property and detailing the changes they have carried out, etc. This usually starts with “We’ve had the damp treated,” & “There is no damp here,” or “We had a survey when we brought the house that identified damp, which we had treated.” What they are talking about is a chemical dampproofing system, often called injecting.
A quick Google search shows hundreds of companies offering this service, but is it needed? On a recent CPD with Stephen Boniface, the former head of building surveying at the RICS, he made an interesting comment that I have now taken as my own, “all things are damp”. Which is spot on, isn’t it? Moisture in the air is essential for life, and therefore, all porous materials must absorb and release this naturally as part of a natural process. This is not a concern or requires a desperate need to panic or spend thousands on damp proofing, tanking, or chemicals. So why are we trying to stop free moisture from entering building materials, as it has done for usually hundreds of years?
So what is it – This has been cut from Google and explains what is involved: A chemical damp proof course (DPC) is a waterproofing treatment that involves injecting a chemical into a wall to prevent water from rising up. The chemical saturates the porous bricks of the wall, creating a water-repellent barrier.
A water-repellent barrier! But what about breathability? i.e., the need for old buildings to breathe; I am sure you have heard Grandparents talk about this, so what has gone wrong? Are old buildings inherently damp beyond measure, killing us all slowly, and we need to modernise them in order to save the planet? I don’t think so. Our traditional buildings were not built damp. Do not accept it when estate agents or builders say it’s an old house, and you need to accept an element of dampness. They were not built damp. Someone has done something unsympathetic, or there is a defect. It is not inherently damp.
So why do we have DPCs? Why did they become standard around 1875 in England and Wales? Are the bottom of all traditional buildings soaking wet, with only the old slate DPC holding back the Amazon River? No. Tests were carried out at London South Bank to try and replicate rising dampness in laboratory conditions, which was a failure. So, if it cannot be replicated, is rising damp real? rising damp is defined as “an upward capillary migration of water in masonry”. Well, sure, maybe! If one squeezes a dry sponge and then places it into a bowl of water, it will absorb the water via capillaries. But that is a suction effect, under pressure, in a bowl of water, is that realistic in a 400 year old stone cottage in Oxford? Well, it is if you are asking a salesman to diagnose the issue with a protimeter. You can bet your pet labrador that the cure will be in the back of his van, and it’s going to solve all of your problems! Or is it?
I have been in the construction industry for over two decades, and it is with a heavy heart I must tell you that not all tradesmen are good, honest and upright people. Unbelievable right? But should we blame the contractors? They are often following a set of rules that I think they genuinely believe half the time. I was surveying a house in the Cotswolds last year when a contractor driving a brand spanking new Land Rover pulled up outside, armed only with a perimeter, and spent ten minutes looking at grade 2* listed property; told me it was all damp and needed about 20 grand worth of damp proofing! I asked if the dampness may be due to high ground levels and the bushes up against the walls. He said, “Maybe, but all these old buildings are damp, aren’t they?” And off he went into his nice Land Rover, probably to count his money.
But why was he there in the first place? An RICS survey has told me I need a damp and timber survey carried out by a damp specialist who is a member of the PCA. We are a member of the RICS, so I will hold back on fully insulting RICS today, but if qualified chartered building surveyors are recommending further investigation, after using a protimeter, who then goes to someone, who uses a protimeter, to recommend a non-sympathetic, damaging method to hide, what may not even be an issue, we must be going mad, or maybe its just me… If I asked a roofer to come and look at my flat roof to see if it needed replacement, what do you think, 9/10 they will say? But an RICS is independent no? Why are they telling you to go to a specific organisation? Why not an independent if they don’t know? Why are they carrying out property surveys if they cannot diagnose damp? More questions than answers this blog is becoming, so I will bring it to an end shortly.
Well, I hope from my tongue-in-cheek blog you can see where I am on chemical damp proofing of any kind. The work is not needed, it will damage the building and can actually cause dampness by creating a passage for moisture to penetrate and create cold spots for moisture to condense.
Similarly, if you are lucky enough to live in a listed building, chemical damp proofing requires a listed building consent. I have seen a conservation officer recently in Salisbury reject an application for chemical damp proofing on grade 2 listed property, as it will “affect the character and fabric of the building.” Hazzah, success! I’m not going mad. If I turn up at your house and you’ve had it done, I’ll be asking for LBC! So be prepared (with tea and biscuits (chocolate hob nobs chocolate).
if your RICS surveyor asks you to get a PCA damp and Timber survey, read this first.
If they tell you your old DPC has failed, call the sheriff to arrest the cowboy! Or even better, to understand how to manage dampness sympathetically in older buildings, contact us here. And, of course, for the best in the game, for an independent damp and timber survey, read this for further information.