The Rising Damp Myth Exposed? Roger's Rant! 

Rising Damp is not a myth. I've seen a few episodes and thought Leonard Rossiter was absolutely fantastic.

It isn't that it doesn't exist it is more that it is often misdiagnosed

Quite a balanced view Roger. Most older housing stock remaining in London was built without damp-proof courses or cavity walls and in the main stays remarkably dry. But ground levels have risen after various owners lay yet another layer of paving over old, until outside paving is level with inside floors. Walls are rendered and painted instead of being left to breathe. Chimneys blocked up and plastic windows installed. Overoccupation of ever decreasing sized properties then pours water vapour into what has effectively become a plastic bag. Cooking on gas releases even more water vapour. Result is condensation, as you described so well, on the colder surfaces. The rising damp myth a book by Jeff Howell the building science lecturer does put a big hole in the damp proofing industry but the RICS are equally to blame for allowing their surveyors to hide behind their damp meters most of whom have no idea of their serious limitations.

I think the problem was with the rising damp industry is they were a lot of scam artists that attributed all damp as rising damp and charged thousands to solve a problem that wasn't there. It was condensation or penetrating damp, especially in old building where the outside ground level had built up above the hard brick course or above vents.

The source of damp is where the confusion comes in. A lot of time it's poor ventilation or penetration.

I have a customer with a small mould issue, no trickle vents, clothes dried on radiators , north facing gable with cracked render, etc etc. Gave the customer some advice, but he opted for getting a plasterer in who hacked off the first metre and then reinstated it, a practice synonymous with rising damp. Only issue is it’s a second floor flat!

Ah Venice, a place where the rising damp is so bad, they use gondolas for transport on it.

British terminology : rising damp Rest of world and science : capillary action (or wicking)

I don't think anyone really believes that rising damp is a myth do they? It's just that 90% of damp cases are not rising damp. I've even seen cases where there is a perfectly good original slate damp proof course and some damp roof cowboy has drilled holes all above it to 'treat'. And of course it didn't fix the issue because it was a high ground level and breathability issue

In the distance I can hear Peter Ward exploding.

As a Building Surveyor, I don't think I've ever met any qualified surveyors who would argue that rising damp doesn't exist at all, just lots who (I would say rightly) believe that the cause of the damp is usually more likely to be something else.... i.e penetrating damp from the exterior, raised exterior ground levels, poor ventilation of underfloor voids, poor choice of plaster/render material, condensation etc etc. The chemical DPC industry is still a bit of a racket, in my view. I have never specified one, though I would never rule it out completely, i'd just want to try lots of other things first! Some of the confusion comes, I believe from some research which was done some years ago at London South Bank University, where they were not able to recreate rising damp in lab conditions. Clearly, lab conditions are not necessarily indicative of the real world, and I took the outcome of the research to be that water moving upwards via capillary action is simply a lot less common than some people think.

Would an air brick in the outer skin of a cavity help to let the cavity breathe from condensation? I have wool cavity wall insulation so I'm concerned that if the insulation gets wet, it will cause penetrating damp. Will some air bricks helpthe wool dry out?

I've renovated a few houses now and had to remove bricks behind skirting to access the cavity to scrape out cement snots. Worse on houses built 100 years ago with lime as some of the lime crumbles down over time. I then attatach a length of waste pipe to a Henry vacume cleaner and suck it all out.

Britain’s expert and guru on damp In buildings is Pete at Heritage House Building and Restoration. He’s an RICS conservation surveyor. I recommend reading their website and watching the videos. It’s eye-opening and very informative. He should be given an award for his relentless exposure of unnecessary remedial works and the real causes of damp. Actually, he doesn’t really believe in rising damp! And incidentally, why show Venice as proof of rising damp? It’s built on water! Most British Homes at worst, would sit on slightly damp soil for part of the year.

Thank you for your excellent video! I've got a question, I've bought a dutch house from the year 1926. It's got a cavety wall but the house wasn't isolated. Every wall mortar course was falling out of the inner walls like sand. Ive had a guy over and he said I need the chemicals injected for the rising damp problem. But I saw the cavety wall is filled with sand from the old mortar. I will clean the cavity, but do I still need those chemicals?

Hi Roger please can you advise my front outside wall have some bricks are crumbling not sure if it raising damp. Many years ago had damp treatment course and the bricks are painted. Can I use storm dry on painted brick and then use dry rods. Hope you can help as I am not a builder. Thanks great video

Buildings need to breath because of the condensation caused by people living in it. Trapped condensation - trapped by modern "damp proofing" methods. It's almost always never actual rising damp, that's the reason given for expensive remediation work.

Knowledge is king, and Roger have more than his fair share of it bless him . The first house I ever bought I did a silicone injection system , which I did my self , it tuck me about 3 days to complete . At the time a lot of companies would have done it in half a day , because they didn’t allow enough time for the silicone to penetrate into the bricks . So it was a totally waste of time , knowing this a pumped as much as I could in till I saw it coming back out of the bricks and mortar . Well that was some 40 years ago now so it would be interesting to see if my efforts payed off in the long run . Thanks again Roger for your tieless work in bringing this to everyone’s attention, because silly statements like your describing could cause a lot of problems for people. Best wishes and kind regards as always 😀👍👍👍

Whats the best solution in your opinion? Tanking slurry or a dpm stud membrane, like newton 803? Done alot of tanking slurry jobs and rendered over always sorted the problem. Curious as the DPM wall membrane seems like a cleaner effcient method but seen some condensation problem vids on youtube....

Blocked gutters are another major cause of damp in homes

Been to a few jobs (usually let properties) where they've claimed it was damp all of the time. Turned out the first metre of roof felt was knackered and rain was trickling down the cavity.

what would you do if you have damp coming through on a concrete floor on a old building that doesnt have a DPM ? obviously could dig up the floor and install a DPM but that would be far to costly ? do you think a liquid DPM would help ?

I have a problem with rising damp in my underground garage in my new build town house. Bessa blocks were used on interior wall, and I wonder if they can be drilled like bricks shown in Roger’s demonstration. It seems odd that damp proofing was not used in construction, as it appears a problem to be expected with 10 feet of soil abutting the garage wall. Any responses would be welcome.

Bought my house (1930’s three bed terrace) about 9 years ago. Was told by surveyor that it had rising damp (rotten floors, damp walls ect) On closer inspection the exterior ground levels had risen above the damp proof course Took ground levels back down fixed all damage caused problem solved 👍

Pizza+beer+Roger rant=ultimate evening

You sorted my head out of fear 😊. I am moving to my last home in my senior years with little funds. You are teaching really helpful information. I will have a go at fixing my damp bungalow. Thank you for helping me out. Love the way you present your advise. Great channel.🙏

Hi found your videos recently, thanks:) Could anyone please tell me what those damp proofing sticks are called? Not seen those before. Also I've an internal wall that is 95cm thick, which has a damp problem. Any suggestions?

As you rightly say, in older buildings, clear out the cavities where snotts over the years have fallen and built up over the DPC level, especially where lime mortar was used in construction, and make sure that exterior ground levels are 6" below DPC, old buildings need to breathe!

Good day if you put in dryrod do you need to take the entire plastet off or only where you going to put dryrods in

Peter Ward will have a fit

Really what most of the people saying rising damp doesn't exist mean that it isn't the main cause. Most people know that when you get called out to a damp issue if it isn't a basement it's going to be landscapers that just completely ignore the dpc and air bricks (yes the brickies point of veiw 😂). And if it isn't that there's leaking guttering or drain. But rising damp actually being the main issue isn't it most of the time, yes the injection damp proofing is probably going to be the most cost effective way after you've spent a few k on getting your new paving.

I’d like to see a video about the most common building control fails, or maybe some of the more obscure regs that people miss. I’m surprised building inspectors aren’t more stringent with keeping the cavity clear

We get it in our stone built cottage, inside the front door. I didn't even bother trying to heat the hallway as it has a loft conversion and felt that it'd be a thankless task because you can look up and see all the way the top of the roof! Also it's in the corner of the living room behind the telly and on the wall that divides the kitchen off. I reckon it's mostly condensation but am wondering if a lime plaster finished with a white wash (or similar) to help let it escape is worth trying. Any thoughts please?

Just love your clear and funny explanation! It all sounds so logic. Keep up the good work!

Great video as always Roger, your rant videos are the best. What would be your advice on preventing rising damp in a rubble filled stone wall with no obvious DPC? Same approach as brick with injection or rods, or would it be different on a old stone walled house?

I’ve always put I’d down to capillary reaction. Similar issue when wet rooms are formed with overlapping joint rather and sealed joints.

Great video Roger, I'm a Chartered Structural Engineer and you were able to sum up the issues at hand here in a very concise way.

Excelland and justified rant Roger ! Damp in buildings is a complex issue and like you say many people are not aware of why it is happening. Most people don't have a clue about how much water is released into the air inside the building each day. Moisture given off by the people living in the building, washing drying, showers, baths etc. Gallons of water floating about in the air which In the hemetically sealed buildings we have to day has got to go somewhere. There's little to no ventilation to the outside to carry it out. It will find cold spots in the building and condense and then black mold will eventually appear and the panic sets in then ! And yes, rising damp does occur - but to different amounts in different materials. Semi-engineering bricks an fresh mortar are usually pretty good at preventing rising damp as are dense blocks. But once the building gets older the mortar starts to break down and that is when it loses its water resistance and damp will start to travel up the mortar joints. The amount of times I have seen perfectly good blue bricks in old buildings that have been drilled into and chemical injection supposedly injectedinto them !! Totally ignoring the cause of the problem which is the mortar in the joints that's failed..

That was a fine rant tonight Roger 😃. What about the surveyors for mortgage companies that used to say virtually every house need a damp proof course installing, I’m sure often it was condensation or damp caused by other things such as faulty fall pipes etc. Not bought or sold a house for many years but remember all those surveys well from the 80s and 90s. It’s just the rich tapestry of life.

Ah you're brilliant. Love your work. I've seen a mock danger sign "translated" from Japanese: "Danger: do not dumb here. Dumb free area." You need one for your shed or whatever.

Hello Roger. Do you have any contacts in the trade who can cover the North East London area (just outside the ULEZ)? I'm looking for a carpenter/joiner, bathroom tiler and drywall fitter/plasterer during winter/spring.

Interesting rant on Rising Damp. You are right, on many levels, including that condensation is commonly misdiagnosed as rising damp. And that a DPC is useful for stopping water rising-up a porous brick. What many people don’t understand is: 1. Rising Damp is defined as the rise of moisture from groundwater. 2. Groundwater being water under the water table. 3. Rainwater in contact with a wall may result in rising damp like symptoms but unlike groundwater, rainwater in soil, can and should be removed through improved drainage. 4. The rise from rainwater in soil is considerably smaller than from rising damp as the soil is unsaturated and therefore water will mainly be drawn down, not up. 5. Like rainwater and groundwater, water from any source can be absorbed up a porous brick, including condensation of a solid floor. 6. Condensation within a wall causes heat loss increasing the risk of condensation. Gravity drawn moisture down and the base of a wall is normally the coldest part of a wall. So condensation is most commonly found at the base of a wall. It expands upwards as condensation increases, for that reason condensation in a wall often appears to rise, leading to condensation commonly being misdiagnosed as rising damp. 7. Chemicals and damp proofers slurry may hide condensation or water from defective gutters etc. for a while, but unless the root cause is dealt with, the moisture will eventually show through. Interestingly no wall suffering from rising damp has been preserved so that it can be studied and learned from. There was an attempt a few years ago, but the wall dried out when it was covered.

What a reasoned argument you give Roger, scientific, balanced & not biased or ranting in any way. BTW: a) how much damp do the Dutch suffer? b) Who says damp cannot rise? it can but not in masonry, it is when the cement is bridged by porus materials such as plaster or a render which creates a capilliary gap..

What do you do if the exterior wall of the house is 9inch concrete?

I own an Edwardian house with rising damp... where idiots filled a conduit channel with bonding you could see water stains tracking up the wall. 😡

I was dying for the toilet, but I saw this video and had to watch it. I'm now experiencing my own rising damp issue.

I live in a Georgian house with rising damp I’ve dry walled it with 25 mm gap between the plaster and plaster board and insulation board no cement use lime make it myself yellow sand lime mix it like butter leave it for two days in a bucket works lovely

Any advice for damp proofing stone walls.

Working for a council I used to be sent to do mould washing which I hated as I think people should wash there own filth ! Is this related to rising damp ? Or just bad ventilation ?

the best way to prove damp rises is to use a length of twine draped over something with the bottom dipped into a glass of water leave for two to three hours and viola the full length of twine is soaked

Put the tip of a towel in some water and watch what happens! Simple. However I assume most people get confused as a lot of damp problems in houses is either poor guttering and drainage or sweating inside

We have a copper coil. When we bought our house the surveyor said we had damp, with their stick indicator, the company who put in the coil and guaranteed it said nope. 30years later we have no problems with damp

Fabulous thumbnail picture for this video. The last time I saw that expression deployed to such great effect was by Kenneth Williams. The subtitle should be “Ooh, I have never been so…”

Fantastic rant Roger, hardly stopped for a breath! Very informative and I reckon you could bust any myth😄

Thanks for name dropping my local town Roger- Back in my school days we had a trip to the NORI brick factory and even got to bring a sample home. Good paper weight and cemented the brand in my mind to this day (pun intended).

On the subject of DPCs you have to understand they date back to a time when buildings were put up using hand mixed porous lime mortar and a huge variety of vernacular materials of varying properties and quality. They make little sense in modern buildings built using OPC and hard fired bricks, yet modern builders seem to be obsessed with them. There is a long standing idea that British houses are built in swamps with only a thin strip of plastic between warm dry comfort and crumbling soggy walls. If the ground is wet then people need to find out why and not just squirt some chemicals into the walls. With damp you have to fix the cause and not the symptom.

I agree completely, problem is when these companies turn up and sell you a damp proof system after using a silly meter on your walls. These damp proof systems cost thousands and in reality you probably just need to redecorate or open a window in the majority of cases, my house being one of them. We purchased a house that our surveyor said needed a full damp proof system installed, cost the previous owner 14k before we could buy it. It now has a stupid layer of concrete on the lower half of the walls that does absolutely nothing other than potentially caus damp issues itself. After spending 3 years renovating the house and seeing the condition of the brickwork, it has no signs of damp anywhere, bricks are bone dry. In this country also, mortgage companies listen to surveyors whenever damp is mentioned and demand a damp proof system be installed before it can be sold. The industry is all wrong and needs sorting out, sooner rather than later.

I was under the impression that damp would only rise about 30 inches ? That's what we were told at college. I saw a documentary several years ago. It was made by a chap who goes around doing inspections on houses for house buyers. He said that in all of the inspections of damp he had done over many years, they were rarely caused by a faulty damp course. there are many ways as to how moisture can penetrate a building. Ground level, faulty RWP's etc.

I'm only 1.5 minutes into your vid Rodger and already I know that you are correct. I'm from England and now live in the balkans, Bulgaria. It's a range of mountains that weave through europe like a snake. I have a two storey house, downstairs is natural stone and upstairs is homemade or village made brick. I am surrounded by mountains and I can watch the clouds being made and rising from the earth from my window, when this happens the temperature drops in my house and I can feel the damp coming up from the earth. I live upstairs only, downstairs is great for storing food and making wine, it has a temperature that is more stable. In the summer it can reach 42c upstairs and remain 25 downstairs. I would say that rising damp is natural, it's the mold that's unnatural because of the lack of ventilation. always keep your home ventilated and most of the problems will disappear. Thanks Rodger.

Also of damp issues are also to do with showers in every home, they create a lot of vapor and it settles on cold walls so if you have a cold home it stays

Hi Roger, could you post the link for that Moon video? Sounds interesting!

I'm a rocket scientist, and I've been to space and I can tell you rising damp is a myth. It's actually aliens pissing against your house at night... and the earth it flat 🤣🤣🤣🤣🤣🤣🤣🤣

My air vent bricks are 8 inches lower than my patio n when It rains hard they fill up with water over the air bricks lol would this course damp ?and next to a gutter drain pipe

It might be more to do with the over keenness to just shout RISING DAMP and then rinse loads of money from the home owner. When more often the fabric of the building itself has been corrupted such as blocked airbricks below floorboards or even overflowing gutters, I just dealt with damp in the middle of a 1st floor wall. We found the condensing boiler outflow pipe hidden behind a soil stack and the plumber had returned the pipe to the wall and moss had built up creating a bridge for water to penetrate.

Our house is 1860, solid walls, slate damp course. No damp.

Hello all! Here from the US, and I'm very confused as to why there doesn't seem to be any dialogue about rising damp here. Am I missing something? Maybe different terminology?

😂😂😂 Good rant Saw you the other day at selco Not gonna lie i was star struck Had to do a double take Couldnt get my words out 😂

Fix a cupboard to a wall and watch the rising damp ruin it.

Very well balanced and reasoned. I believe in rising damp! However, I'm less sure about certain parts of the damp industry. First comes the general surveyor, who sticks his moisture meter into various surfaces and opines that there might be damp and recommends a specialist. But there aren't really specialists, or many of them anyway. There are only firms that cure damp, using a variety of methods. But was it damp in the first place, or condensation? Well, these firms aren't going to say it's the latter. This was my experience when I bought my house seven years ago. The firm I engaged diagnosed damp more or less all through the ground floor. The remedy, to hack off all the plaster (filling up a whole skip in the process), injecting some kind of gunk and then re-plastering with plasterboard and skimming. So the damp appears to be cured but I have the feeling the whole thing was over the top. (And my pocket felt it at the time, to the tune of c £2500). The dry rod method which you recommend looks a lot less intrusive and more economical in expense and time. Were you on RU-vid seven years ago?

And the answer is 'Yes!' This is why you don't see sodden saturated bricks on canal bridges!!! The only Rising Damp I have ever seen is the comedy starring the late, great Leonard Rossiter :).

Anyone noticed how once damp starts rising it goes all the way up a wall to the top of the ceiling (especially in cold weather when it's far too cold to evaporate)? Me neither.

Thank you for these videos, love your content lots of useful information. I have a house that Im refurbishing which has no cavity with all walls being lime plaster. Most of the walls need patching or re plastering but Ive been told not to replace it with gypsum as it doesn't breathe. I thought about leaving the lime on the external walls, then batten off and plasterboard creating an air gap between the new boards and old walls as I want to prevent any penetrating damp down the line? Id love to hear your thoughts on this.....

Could you consider rising damp a form of passive cooling in hot dry climates?

Rising damp is very common in Ghana and people are just tiling thinking it's solving the problem. Eventually it rises above the tiling level to a point beyond repair. The blocks here aren't very good either.

Can you make a video about fugus in houses especially black mold on walls?

A well known local damp proof company recently hacked off and rendered to 1.8 metres when thirty years ago it was 900mm, fifteen years ago Is was 1200mm. This tells me that the capillary action is simply climbing further with each increase. Pointless. Somebody needs to tell them that trees can draw water to over 100 feet just through capillary action so what they are doing is just fighting a losing battle.

What is the point of putting a bit of plastic around a row of brinks to stop the damp, if they then put so much cement on the brinks that the plastic get covered over??

Excellent rant. The topic doesn't interest me but I love a good rant, whether it's me doing the ranting, or listening to someone else's. A good rant is one of the best forms of entertainment.

No it's a comedy show Lenard Rositer Epic show I still watch to this day!!

good job covering the subject but I'd still never inject an old house

I live in Cornwall... Nuff said,thanks Rog 👍

"Rising Dampness" is a simple process called capillarity.

Excellent rant Roger and totally correct! I did work for a remedial treatment company in the early 90’s. In hindsight I only found one case of ‘real rising damp’ where the damp had risen to approx 900mm which was in an old empty house, quite fascinating to behold if I’m honest, it was a textbook case. The ‘failure of the damp proof course’ is in the main a myth in my experience. The main cause of damp in properties is down to many issues; condensation, blocked cavities, hygroscopic salts, penetrating damp where walls are solid, and one of the worst in my experience ‘sulphur salts’ caused by penetrating damp down a chimney where no cowls have been fitted and the chimney is no longer in use as an open fire place. In my experience chimney breasts do not have a dpc and once decommissioned as an open fire tend to suffer with rising damp as well as penetrating damp where rain can get down the flue and they are not vented. If used as a flue for a gas fire, this is further exacerbated as gas is a ‘damp heat’. The end result is yellowing damp patches on and around the fire place. If you have solid walls and suffer with penetrating damp then I would recommend ‘Storm Dry’ (no I am not sponsored by them, I’m just a building inspector). This is a breathable membrane which is applied to the exterior of the masonry which is totally water proof but allows the masonry to breathe and release moisture from within the wall itself. It is also guaranteed for 25 years and drys clear and colourless. If you have cavity walls and you have areas of damp, remove a brick on the outer leaf where the damp area is and check that the cavity is not blocked. If it is then clean it out and maybe replace the brick with an ‘air brick’. If the cavity is clear then look under the floor to the internal leaf and make sure the dpc is not breached by previous ‘builder’ activity. Any joist ends should be checked as well where there is a breach to check there is not rot to the joist end. The ultimate dpc failure test is to do a ‘Speedy test’ although this test equipment is usually only used by remedial treatment companies.

Cracking rant! We had rising damp in our old utility room- the walls were literally damp to touch when we moved in. DPC was being bridged by some badly laid concrete. Cut out the edges, and left a gap between the slab and the building. Left the plaster as we knew the room was going tk be replaced. Dried out within weeks and stayed bone dry for 4 years until I knocked it down.

Thanks Roger, your rant has brightened my Sunday morning!

Dehumidifiers work well removing damp & dry air feels warmer handy in a bathroom

Love your videos. Great presenter 👍🏼

I think you’ve missed the point. Moisture will only wick up a porous material. If you put an engineering brick in a bucket of water the exposed bit will stay dry as opposed to a thermalite block which the water will travel up. Same story with mortar, Portland cement is pretty much waterproof. As you say, almost any structure built in the last 200 years has a DPC whether slate or plastic. I’ve yet to come across a building that was actually suffering from riding damp. It’s always been raised ground levels outside, poor drainage/gutters, leaking pipes etc, drying washing inside, modern showers, leaking roofs. Most of it can be solved by simple stuff like lowering ground levels. Dealing with rain water ventilation etc. So in a way I’d agree rising damp is a myth. The products like dry rods, injection creams, galvanic system etc are 100% snake oil.

I had a damp issue in my last house, solid brick Edwardian end of terrace. The council had relaid pavement ok the side of the house prior to us buying. I didn't realise that this would cause an issue when I bought the house, but the level of the pavement, outside was higher than the floor in the house. So yeh, damp in the walls. I spent blinking hours on the internet researching the issue and came to the conclusion that there wasn't much that could be done. Previous owners put an injected DPC in the walls, but this just trapped the moisture between the floor and the injected DPC, so any plastering between these would just blow eventually. The council were never in a million years going to install a French drain between the pavement and the house to stop prevent the issue. I sold the house and the new occupants tanked the wall, I would be interested to see what that did, I would imagine that it would damage the bricks eventually as there would be literally nowhere for the moisture to go.

Good vid as always Rodger, more rants please👍😉 I still can't seem to find that crashed spitfire on the moon😂

Rant so so worth listening too. You have probably solved one of my issues.

01:51 Is that tall building tilting, or is it just my imagination? 14:57 This actually does sound really interesting. Kind of wish you'd shown some pictures or just talked more about preventive methods.

I just love ypur videos amd appreciate your passion. I would love to work with-for you and enjoy your skill, knowledge, passion, and personality. Thank you

Some people say I have a dry sense of humour. I think it is damp.

I have a problem with falling damp, i have been told this is due to gravity....the moisture can't escape because it is stopped by the damp proof course.

It all started with a tv dicumentary in the 1990,s which said it was a ventillation problem .They placed a stack of bricks in a tray of water six inches high and the moisture etc never went up the stack of bricks.

We indeed got a lot of rising damp in Amsterdam mate

bba certificate so it does work… yes like grenfel cladding , cavity wall insualtion, etc

The end shot of the moon is pretty funny

Brilliant. Thank you.