Thank u good sir I’ve had similar issues in my property. Wally damp man advised me of rising damp slurry on wall etc. Didn’t ask me anything about the sub floor etc or gutter. So I took off the floor boards and saw an undersized air vent that was virtually buried plus a lot of dirt in one corner that was upto the base of one of the internal walls.
Your the man. My home has risen front and rear levels outside, with half blocked front vent and blocked rear from where it's close to being water logged. I've cleaned up the vents , my home smelt musky and felt humid I hope this may change things and the problem resolved. .
love these videos. just bought my first house and the previous owner tried to hide a damp problem by covering the damp wall in wall paper. now the wallpaper is starting to peel off. the survey i had before i bought it mentioned possible rising damp. I can see the previous owner has had holes drilled and injected. having watched a few of your videos i can see its simply the fact that the pavement is at the same level as the air brick thanks
More than likely - make sure you have good air flow under the floors too - one air brick is not enough. You need through flow - which may be blocked by, for example, concrete flooring at the rear that was not there before... Keep humidity down in the building... monitor kitchen, bathrooms etc and make sure plenty of air flow and ventilation. Take wallpaper off - scratch and chuck water at it - steam is not good - it will blow plaster...
I wish I could - mostly these are done on surveys, so we dont often get to see results. I do try to stay in touch, but getting those finished videos is not easy!
Great video I lived in my house over 10 years had damp man come out an say I have rising damp he injected all around went off with my money an still had damp comming through had another man out an he said no not rising damp as house built on lime base and to put air bricks in where old ones had been taken out hmmm great video I will be following 😀
i do love your videos. i.m in the process of clearing my subfloors removing historic osmosis strips and cleaning old air brick and adding new ones and adding telescopic vents to reachthe sub floor from pavement level
Thanks Alan - glad to have helped. Hope everything works out. I've just released the new book - Warm Dry Home - which is on the Heritage House website here: www.heritage-house.org/products/the-warm-dry-home-1.html - I'll do a video soon, so more folk get to know about it.! Have a good Christmas!! Pete
Liam - its not easy as there is no properly defined training route. Most of our crew have come through practical building work, into qualified surveyor route - either through rics, or building survey study, coupled with professional experience. The CIOB are starting more training courses - and we may be doing CPD courses ourselves soon.
What type of professional do I need to talk to locally to do a similar diagnosis on our house? I've spoken to a damp proofing company about damp under the floors but they're not interested as there are no signs of damp above the floorboards.
Really appreciate your videos. Is there a recommended amount of air bricks to have per room. At present we have 1 at the front wall and the back wall in each room. There's 3 rooms downstairs, varying 12-15ft wide x 20ft long. The 20ft is the distance between the vents. Also i did see you mention in a previous video what the recommended distance from the outside vent to the ground level but i can't find it now. Any idea what this would be. Much appreciated . Thank you Peter
Ok... i asked you in a previous video where i could learn your knowledge. I must have watched about 20 of your vids now, i'm gaining knowledge but i still ask the first question, where can i learn your knowledge? Do you run courses?
Brilliant videos Peter. Have had a lot of problems with damp at my first house too but your videos and heritage input for the Victorian house book is a lot of help. Our house in Lincoln is on a hill and sits on clay and they have raised the ground (patio) level with concrete at the front and back of the house which I'm looking to remove. It seems as if the clay is only 1 brick level below the air brick. Should I dig lower or would that be a sufficient ground level? I'm also looking to replace concrete with brick pavers.
Thanks Peter Will letting the building breathe heat the place up? Ours is getting very cold and we were thinking of using chimney sheep's to stop cold air getting in. Good idea?
Ideally lower the ground. It's lovely to feel a breeze blowing below the floor. You won't get a breeze through those submerged vents. However, clearing the vents is an absolute must.
Thank you Peter for your insight. These videos are so informative. I wish I’d watched this before obtaining the services of a water loss agent! We have water ingress under the sub floor which was coming through a partially blocked air vent. We’ve now removed patio, dirt and gravel to approx two bricks below the air brick. We’ve been advised to put a damp proof sealant on the external wall (dig to foundations) and install a field drain. Would you recommend putting on a sealant? Also, underneath the floorboards the bitumen solum has a few holes where the water would sit in pockets and we’ve been advised and quoted to seal the solum in visqueen/concrete. Is that necessary or would that cause problems if we had water ingress at a later stage? Any advice is appreciated.
No to the sealant - just makes things worse. Leave the solum - ventilate it so it doesnt get so damp. Never use plastic. Dont seal walls, and dont dig trenches cuz they hold water into the trench and make it worse - if you MUST, make sure its a sealed trench, lined with fabric, pipe in bottom draining to a storm drain, filled with clean pea gravel. I hate them!
@@WarmDryHome Really interesting videos, thanks Peter. We definitely did the right thing on our old stone cottage. Removed the concrete and rendered with lime. Removed all the wood chip from the walls and ceilings (nice lime plaster underneath). Stripped and repainted the old sash windows that had been painted shut in the 60s. Only thing you've just worried me with was the use of French drains. They seemed a very common solution to high ground levels in all the traditional building renovation books I read. Are the not a good idea?
I too am interested in this statement re french drains etc. I read it as you can cause more problems if you simply dig a trench, as water will fill it, and hold it close to wall. Building decent french drain, say into sustainable wrapped cages (modern version of soakaways) , I am not at all sure why that would be a no no ... Glad the back to basics worked for you ... Modern brick paving laying gangs (sorry companies) concern me as they pave right up to external walls at quite a height (:-((((
Hi Peter are those type of air vent gulleys useless or do they just need clearing. They seem to be open to the elements and act as a lovely drain for rain water. How would you re engineer the exterior to make them efficient as I have this problem, thanks for your time Chris.
I would say they work. My friend and his father excavated under the floor boards to take out bags and bags of rubble and earth, increasing the air flow from front to back of house using exactly these bricks. Added one new brick under hallway door which did not have an air flow. Damp problem disappeared, with the breeze. Certainly in their case it worked just fine given sufficient air flow ...
@@colincampbell437 Thanks for the reply. I have a Victorian cottage with a 4 inch single skin extension on the back. Just had extractor fan fitted in bathroom in extension and upon drilling the hole noticed that they are plasterboard walls with about a 5 inch gap and fibreglass insulation in between. The insulation is quite damp and smells musty but has never caused a problem before. I suppose we need some form of insulation for a 4 inch wall, but maybe celotex would be better. Have you ever come across this situation. Thanks for the time you take with posts and replies etc. It is much appreciated,👍
@@Tittytotter the efficacy of boards is not really something I have had experience of. I have used insulated plaster boards on my daughter's council flat and 20 years ago on my son's bedroom on one external wall which caught the full force of cold winds. Both performed well, but we're on different walls to yours. I have seen celotex used by builders/roofers under external tiles on front of houses (typically bays), where they tend to be single skinned. However I do not have any feedback on their long term performance. Sorry ... My experience in past with extractor fans was not good re change of air. I assume you can measure their real performance with a humidity meter, which are amazingly good value these days. My daughter's experience with one in kitchen is ok, but bathroom very weak. Although she is a leaseholder we are not allowed to change it ... (:-(((( . Madness....
Great video. My subfloor vents have been sealed for the front room (living room) by the previous owner (2 up 2 down gabel end red brick terrace) The problem is the back room (kitchen) is a concrete floor so i don't think I'll get air passing all the way through? I'm guessing it's still better to open them up but because they're so low I'm worried rain water may come in. Would it be best to put a air brick vent cover over maybe and open them up?
Ideally external ground level needs to be 150mm below internal ground level. Originally, kitchen would have been connected to the front, via air vents to get through flow. Yes, if the front is suspended, you need those air vents exposed. Ground must be below them so water cannot run into them. Do you have problems, or is this just observation at this point? Also check stormwater drainage - downpipes, etc - do they discharge INTO gulleys, or discharge over the ground - make sure all storm water goes into drains - and that those drains are not cracked underground - ideally get a cctv survey - and ensure that storm water is taken away. This helps keep ground at low level nice and dry.
@@WarmDryHome thanks so much for your reply. I just measured it I would say it's about 100-120mm below at the front and over 150mm below at the gable end. I will defo get them open at the front then, just a little concerned if the rain comes towards them as they are old vents with big holes. I'll probably get some newer ones fitted. The front ones are about 25mm from the ground, is that too low? Would it be sufficient to have open vents on the front and gable end? The gable vents are newer plastic style ones. Not sure what I can do about the back as that room is concrete. The floor in the front room is bouncy, I've not had it all up but i would say the joist and floorboards are probably on the way out. There are no downpipes on the front just gutters. I don't think anything drains on that side.
just moved in to an old house which has no DPC or air bricks. Ive also found out that it has blown insulation in the cavity which was wet when I took part of a wall out. the bricks show signs of crumbling. plaster was all blown on the outside wall. where do I start?
Crikey - that's a handful. Might be best if you email peter@heritage-consulting.org and we'll have a chat. The CWI will be subject to 'guarantee' which involves a fair bit of process and determination to get it removed at their cost - blown bricks need to form part of any claim for re-instatement. Blown plaster may be from CWI, or excessive moisture in building from things like blocked air vents. As I say - a bit to look at and interpret - but we'd need to see details...
Another great video. When ever I get asked about a damp property, increased ground levels are the first thing I tend to look for along with blocked sub floor vents. BTW, did you play Bayleaf in Londons burning in your younger years? ;)
Thanks! Alongside those things, keep an eye out for leaking drains - they are such a common cause of problems... No - my film stuff mainly confined to restoring old houses, though did appear in a couple of dramas with my horses that were filmed in Cheshire in the 1970-80's.... Long time ago!
carl6985 hi i am wondering exact same question , thanks for all the video and advice its great to see a builder who actually knows what he is talking abou
I presume any existing dpc has been bridged by the external concrete yard. Would the timber sub=floor dry-out natuarally then ,when the yard is lowered ??
paul gould Good theory, and you are probably right - in conjunction with good ventilation - you need a good draft of air under sub floors - through flow - no point in just having a vent at one end - nothing will happen. !
I paid £140 for someone to come out, stick my wall and tell me I have rising damp. After these videos, I think my problems stem from a risen ground level which hasn't been pointed out. At a bit of a loss how to fix
Sort the ground levels first - to 150mm below internal floors, check all stormwater drains - cctv survey - and dig up any earthenware gullies and check them! Internally, monitor moisture - ventilate well - no more than 7 grams/m3 water - at 15 degrees C and 50% RH - which stops you getting any interstitial condensation. If internal plaster is failing, might need to replaster using lime, but do the outsdie preventative stuff first, and lower moisture stress...
@@WarmDryHome Mr Damp man was round today and got a rough quote of £3000 to put a membrane into the wall. He wasnt very interested in looking at the air bricks outside
@@dVC407 Complete con - Cox are the worse of the con artists around. Uninformed rubbish. They never want to go for the simple, inexpensive option - just to defraud. Why I will never know - but I guess £3k as opposed to abut £50 for mre air vents... Need to properly sort your place though - as always, shout if you need - peter@heritage-house.org if need to email photos etc...
Hi Peter. Thanks for sharing all your knowledge, an amazing resource. There is one question I can't seem to find an answer for; and that's whether and how to remove an injection damp proof course? I had it done years ago and some problems have arisen, exactly as they have done in your on site videos. Is it a case of drilling it out and filling holes with lime mortar? Any advice would be greatly appreciated.
Almost impossible - you'd need to take out the damaged bricks. We've noticed recently that more and more of injected bricks we see are spalling - I think there is a long term latent defect rearing its head here, in that whatever rubbish is impregnating parts of the brick is actually causing damage. I'm very much of the opinion that if it aint broke, dont fix, but if there are clearly issues, you may have to replace. I'd try raking out around the bricks (with an arbortech - not an angle grinder which damages the bricks and allows water into the brick edges and damages them) and re-pointing with a soft, preferably hotlime mortar..
