How to fix rising damp & penetrating damp - (PART 1). Lower floor, remove render.

How to fix/solve 'rising damp' problems in a solid wall (no cavity). Penetrating damp? Chemical injection damp proof myth?!!! I show how to lower a path, install a french drain, install a channel drain, and connect a foul sewer. On this Victorian house, previous chemical damp proof did not work but some simple cheap methods did. I hope you find this video helpful.
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Rising Damp fix Part 2 - • How to fix rising damp...
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#risingdamp #fixrisingdamp #penetratingdamp

[@tanyaroyredcar]

Totally spot-on advice. The cause of much "rising damp" - which is in fact a term created by the damp-proofing industry. We had a driveway which was higher than the internal flooring. Previous owners had tried all sorts, had "tanked" a 400 year old building, injected it with chemicals, removed lime plasters, introduced gypsum plasters etc and simply made the problem worse. We removed the plasters and cement from inside and dug a french drain outside. Problem has gone. This summer we plan to replaster in lime inside and the building will be back to original.

[@POUSEaroundtheHOUSE]

Sounds like you have it nailed. I think lime plaster internally is the way forward. I've yet to do that to mine, but to be fair dropping the path and french drain seems to have done the trick! Thanks for the feedback and good luck with your project.

[@TheAudiostud]

Right I'm here and thank you so much this is exactly what we've got

[@POUSEaroundtheHOUSE]

No problem.

[@ganymede4563]

I had exactly the same problem. The person who had the house before me had added a layer of concrete to the path, then a layer of tarmac, then another layer if tarmac, so the path was level with the skirting boards inside. These were rotten and had colourful mould behind them. It's all sorted now, and it's really satisfying seeing it dry out. Great video mate!

[@POUSEaroundtheHOUSE]

Hi there, apologies, for some reason I only just saw this comment you left. I didn't get a notification 7 month ago! Really great to hear you fixed your problem. As you said, really satisfying to see a cheap robust fix make such a difference to the interior and great when you do it at little cost all on your own! Thanks for your feedback, god luck and thanks for watching!

[@khw_]

I know this is an old comment, but what you described is exactly what we’ve discovered in our back room and I’m a bit clueless! Did you fix it the same way, by lowering the outside level/making a trench? Thanks

[@MarcusT86]

Been behind on my video watching for a while Pouse. Going through new vids again but old favourites like this. I’ve got a semi detached cavity wall build. No damp as of yet but as part of the renovation I want to ensure I’m doing what I can to prevent any in future. My old concrete path around the house is less than 150mm below the DPC so eventually I want to break it out and lower it with a nice patio path. I noticed in a response you said you used a Titan breaker for yours. I was thinking I’d need to do the same but I’m terribly paranoid about breaking concrete so close to my foundations and lower brickwork. Not hitting them but just the immense vibrations. Is this being paranoid? Haha

[@POUSEaroundtheHOUSE]

If you have a cavity wall and no damp issues then I probably wouldn't mess around as it sounds like it's ok, but if you're doing a new patio and just want to lower the new patio a touch then fair enough. If you're really worried, try grinding a length of concrete near the house first so when the concrete breaks it will break out to that line and not try to pull in close to the house. You can finish the rest off once the bulk is removed and carefully take it out up to the house. But you have to be a bit careful as you never know what lies beneath, main water pipes, sewer, gas, so just take your time. Also foundations on old house can sometimes be very shallow. But just remember if it ain't broke sometimes...don't fix it!

[@MarcusT86]

@@POUSEaroundtheHOUSE thanks for the advice again buddy!

[@charlotteblakey7967]

Very helpful, the outside path on the side of our house is above floor level and we're getting rain water coming in! Unfortunately we don't own the path (back of other houses) there seems to be a small channel between house and path but as we don't own the path I'm unsure what to do next and how to fix the water issue inside :/

[@POUSEaroundtheHOUSE]

Sounds like a pain. Well best of luck with it, hope you get it sorted. Thanks for watching.

[@markjewell911]

should be sueing the council!!

[@alanyoung7532]

Good common sense approach. Very wise not to call in a so called specialist as some of these would have recommended a another injected DPC - because the first one has failed!. Building Research Establishment Digest 245 (Rising Damp - Diagnosis & Treatment) recommends dealing with all other potential sources of excess moisture before a detailed Rising Damp investigation is undertaken so you are in tune with best advice.

[@POUSEaroundtheHOUSE]

Thanks again Alan. I'm a great believer in process of elimination. Fix the obvious first and then go from there. In my case, it worked, but with solid (non cavity) walls like this there will always be an issue with cold, condensation especially when gypsum plaster is on the inside wall. The only way to overcome this completely in my opinion is to clad the outside with timber or slate to protect the wall from rain and warm it slightly, or possibly where there is room, build a cavity wall to the outside of this and insulate the cavity as with a modern block cavity wall.

[@alanyoung7532]

External cladding sounds favorite as you could possibly add a breathable thermal insulation between the battens. This technique is likely to become ever popular if we are to reduce our energy consumption. It will also reduce internal condensation.

[@MrOrangeman18]

I have a similar problem. But the outside is a lot lower then the kitchen. The whole rear tenament was wet. It's been re rendered and upstairs has dried. But the kitchen where all the cupboards have the plaster has all come away. I've been told only injection will fix it but after watching a lot of videos it seems like it won't do a lot. There's no drains or guttering against these problem walls and like I say the tennament is higher then the paths out side. Yet the walls where wet. Is it a case of let it dry out and starts again with plaster or what else would you recommend. Many thanks

[@POUSEaroundtheHOUSE]

I'm not an expert in this field I'm just going on my own experiences and research on old properties, but you may find if you have a solid wall, the walls stay cold especially closer to the floor as the cold from the ground keeps the temperature down. This means that if your kitchen has lots of moisture in it (which kitchens usually do from cooking and washing etc) then the air will often condense on the cold walls appearing as damp when actually you have condensation. If you have cupboards over the wall the moisture never really escapes. The bricks remain constantly damp and cold and they never really dry out. Gypsum plaster and cement render trap moisture in the bricks and don't allow them to breath, and all this combined with possible penetrating damp from driving rain on the outside causes 'damp' walls. The real solution is to strip the render and plaster, let it dry out and then use lime plaster and render which is breathable. But I know that is often not often a cost effective solution. Something I've seen done in the South Wales valleys is to slate your wall (on the outside) like a roof, using roof batterns on the wall and nail slates to the batterns (just like a roof) which provides a waterproof wall so driving rain can't reach the brick. I drilled ventilation holes through my walls behind my kitchen units which helped the air to circulate. You could also try Peter Ward on youtube as he seems to know about improving damp in old buildings. Hope that helps. Good luck and let me know how you get on. Thanks for watching!

[@pjroberts2010]

My DPC is the same level as the ground outside. It's new build house, timber frame. I'm not sure what I can do. I believe the DPC needs to be a min 150mm above ground level but i'm not sure if this applies to new build timber frame. If I laid a path, stones, patio etc around the house it would cover the DPC. A builder recommended me to dig approx 1ft by 8inch wide footing around the house and fill it with concrete covering the DPC. I would grateful for any advice :) The damp proof has been approved by building regs but i'm thinking building regs made a mistake.

[@POUSEaroundtheHOUSE]

I'm no expert so I wouldn't like to give advice on timber frame. Although I would have thought you want your DPC 6 inches above ground level. My house is solid brick (No cavity) so penetrating damp was an issue. It may not give you any problems on timber frame. If you can lower the garden around it that would be one option. Maybe speak to building control, if they say it's wrong, get in touch with housing company to put it right if it's still under warranty. Sorry if that hasn 't helped. Best of luck with it.

[@pjroberts2010]

@@POUSEaroundtheHOUSE Thanks the for the reply. I'm unable to lower ground level because the step from the house would be too high. I think the developer messed up the DPC. Was reading DPC needs to be min 150mm (2 bricks) above ground level to avoid splashback, i can only guess its the same for all houses. I'm awaiting a reply from building control because they signed it off , but i think they made a mistake. I'm not going to cover it as the builder recommended as it will trap moisture. Thanks for all the detailed videos they are really helpful.

[@roberthamilton2334]

Hi buddy, I have a kitchen floor moulded and very damp nobody can find a pipe leak. If I put in a french drain like yours would it drain away moisture away from center of kitchen floor. I can't dig as far as footings because I can't get a soak away, but probably go down 400 or 500 mm like yourself for a drain? Thanks in advance!!

[@rubyg8389]

I have a question, I'm in an old terrace house on a bank so my yard is built up higher than my floor inside my living room by probably half a meter but level to my kichen floor. Do I need to dig down to the floor level of my living room?

[@pjroberts2010]

How can you install a french drain with drains and gutters in the way around the property?

[@POUSEaroundtheHOUSE]

I didn't have a drain this side of the house hence why I was able to add a French drain then add a channel drain. Thanks for watching.

[@df6756]

good work. I have a road at the side of mine, same issue. should I dig the road up. it's higher than my floor level. can the council sue me?

[@POUSEaroundtheHOUSE]

I think you need a solicitor to answer that question! But yes ideally any floor level outside the house should be at least 6 inches below the inside floor level. Best of luck and thanks for watching!

[@alexquinn9213]

I want to have my patio to the door sill but that would mean going above the dpc. Do you think there is anyway to do this safely?

[@POUSEaroundtheHOUSE]

Hi Alex, if you are just putting a step in front of the door, then you shouldn't get a damp problem as the door is metal/uPVC and glass which won't absorb moisture. But I would never bring the patio above DPC level. I guess your talking about having the outside floor level flush with the inside floor level? It looks nice but usually isn't very practical! If you have a cavity wall, again it's not good practice but you may get away with it (but I wouldn't advise it), but if you have a solid wall (i.e. no cavity) then I would avoid at all costs. Hope that helps. Let me know how you get on. For regular vids please subscribe, good luck and thanks for watching!

[@jillratcliffe7119]

Was there a damp proof course below ground level which was breached when the concrete was put down or did you install one after?

[@ratclifferob]

Hello i have moved house and the external wall has had small drill holes filled in, should these holes have been filled in or was they there to let air in ? I have a bit of mold on the wall where the chimney fire place has been filled in behind my couch. There is also 2 small air vents that are not blocked on the same external wall.

[@twinnydb]

Hi, Great job by the way. From what I have seen so far regarding DPC, I am very sceptical that any of that actually works. This video, as well as other I have watched makes far more logical sense! I have a very similar problem with water splashing onto the brickwork from the driveway outside (same level as my floor boards) and causing damp through the walls, however I also have a basement below our floor level which is saturated, particularly the walls on that same side. It would seem that water has been penetrating through those walls for decades and the walls of the basement have been covered with a cement mixture and this has simply not allowed the bricks to breathe. If I want to install a french drain, would you suggest digging down to the foundation level? Or Installing one outside as well as within the basement (with a sump pump).

[@POUSEaroundtheHOUSE]

Hi Twinny, to be honest I'm no expert in this field, I've just done a lot of research on this, used some logic and combined it with some diy skills and mine seems to be doing a great job. If you have walls all the way down to the basement with proper foundations below basement level, then in theory if you can afford to loose a bit of space around the side of the house, you could dig down to basement level on the outside of say a paths width so you can walk around it. This would remove all the soil / earth from the outside of the wall and it would no longer be under ground. This would stop water penetrating. However you would still need a way to get all your surface water outside back up to the drains and digging this deep could cause you basement walls to collapse if they're not solid or structurally sound. Just a thought! If I had the room around the house, that's what I would do. Could even put a door in the basement to the outside then. I'm getting carried away now! Hope that helps. Let me know what you decide to do and how you get on. Thanks for watching!

[@HalfManThirdBiscuit]

twinnydb You should check out Peter Ward’s yt channel. Damp proof wallies get short shrift from him!

[@karenrayner839]

The reason the chemical dpc did not work was because the render was left in situ, the water from the path was going onto the render and going round the dpc. The original render should have been removed before the dpc was installed and the wall treated with a tanking system if render was to be replaced. Dont get me wrong I totally support what you have done here and it should have been carried out at the same time as the dpc was installed. Chemical dpc treatments installed correctly with the necessary associated works will do the job.

[@POUSEaroundtheHOUSE]

Hi Karen, the problem I have with this system is it's always advised to tank and re-render. This is essentially what dries the wall out, then finishes the wall nicely with new render...all good you might think. Then 2 years later the damp is back. In my view because the creams don't really do a lot. Once gypsum plaster gets wet I've noticed it will hold the water like clay and I think that's one of the biggest problems. On a solid wall with no cavity, probably avoid render, and gypsum plaster is best and except the wall will always be cold and cause moisture vapour to condense on it. So good ventilation on the inside is essential, but keeping water off the outside is a good idea. I'm no expert but just going on my own experiences and that of friends. I've monitored my house carefully and know what does and doesn't work. Thanks for the comment.

[@TheNomadicTrader]

H mate - we have rising damp in our back room in a 1930's semi-detached. The drain at the side of the house apparently wasn't reconnected a while before we bought the property. As a result the ground underneath the suspended floor is saturated but not pooling. The house was build with a slate/mortar/slate DPC configuration which is being breached in certain places at different degrees. We're having the drain sorted, but I am also considering doing this myself next summer. There's no channel around the house or any obvious signs of well-thought runoff built into the design of the groundworks. I was wondering if there's anyway I could share some images and get your advise please? I've had a few 'specialists' survey us, but they have only recommended we DPC cream & install membrane 1m up the walls. Thanks in advance. Rob

[@POUSEaroundtheHOUSE]

Hi Rob, I'm not an expert by any stretch so I'd be reluctant to give 'advice' as such. However what I can say through my own experience is to do all the obvious things first. Get the outside ground level 6inces or more below the inside (or slate dpc if you have one). If you have cement render, it maybe be worth trimming it back to let your bricks or stone breath and dry out. The only problem with this is sometime the bricks underneath have been ruined by the cement so don't look great. Check all underground drainage and sewers and make sure they're not leaking into the ground. Keep gutters clean and unblocked. Often I believe it's penetrating damp, not so much rising damp. My house had already been injection damp proofed by a previous owner and the damp was above it. I would have a go yourself first and see what happens. Hope that helps. Thanks for watching and keep me posted on your progress.

[@TheNomadicTrader]

@@POUSEaroundtheHOUSE we've hacked off all the old plaster, turns out it was the old plaster retaining the moisture. Drawing in the moisture and not releasing it. Once it was back to brick we got the suspended floor up, cleared out all the junk under the floor (a void about 60cm), improved the ventilation, damp proof membrane around the bottom 1metre of the walls and dabbed thermal boards. It's finally finished and looks amazing. Whilst the floor was up we insulated it between the beams and replaced the old flooring with moisture resistant T&G

[@Fantusdrake]

What tools did you use to cut the path n drill path

[@POUSEaroundtheHOUSE]

A Titan angle grinder and a titan concrete breaker both from screwfix. Thanks for watching.

[@Fantusdrake]

@@POUSEaroundtheHOUSE sorry again the grinder I was using doesn't cut deep enough what type of saw else did you recommend

[@AutoFreak10]

Thanks for the reply and I have indeed subscribed to your channel. I live in a mid terrace house with solid brick wall at the front and then an extension at the rear which is only a few years old so fortunately for me, I only have one wall to be concerned about. I have 2 air bricks on the offending wall and the damp that I have inside the house is in line with these. I stripped the plaster off from the inside of the wall and lifted the floor boards and did indeed find that due to the ground level being to high, the air vents were badly blocked and damp. I will make the trenches that you show in your video and do as you did with the perforated pipe and gravel. I have noticed a strange thing being that although the vents were blocked and there was definitely damp coming inside from there, there is also one random wet patch on a brick that is about 3 high from my floor level and no other bricks below or above it are wet. I checked outside and found no holes that have been drilled etc but I found this strange and might have to get someone to look at that for me as I would hate to go to all the trouble of getting re plastered and then have another problem. The joys of houses eh ! :)

[@POUSEaroundtheHOUSE]

I have also stripped some render off the outside wall above the worst damp patches. This has not only allowed the bricks to dry out and breath a bit, but I discovered some large gaps between bricks where mortar was missing. I assume this is due to weathering many years ago, and instead of repointing, someone has rendered the hole lot with cement render. Now the render isn't great, water has got behind it and worked its way down through the missing mortar which maybe the problem you mention. So I have since pointed the gaps with a hydraulic lime mortar (1 lime: 2 Sand). Unfortunately some of my bricks don't look great under the render, and half of my render is now hacked off, but being dry is my main priority for now. I may consider some cedar cladding in the future on the most exposed wall to provide protection from driving rain, and smarten it up. I'm hoping that will keep the bricks dry, and leave a good air gap between the cladding and bricks which may do the trick. Old houses certainly have character, but they keep you busy!

[@tamariderr]

Great vid some very sensible points. I have a question tho.. if the cement render is impervious to water (hence the problems with cement based mortar / render compared to lime based) then why is water splashback able to penetrate and soak the underlying bricks? Thanks

[@POUSEaroundtheHOUSE]

Problem is it's not really fully impervious, it does get damp so moisture can work through even with waterproofers etc in my opinion although they probably help. But biggest problem is all render cracks, even tiny fine cracks and often higher up the wall, sometimes 'popping' and coming slightly away from the wall. Small amounts of water and moisture get in behind it but struggle to get back out so bricks can become damp, and then stay cold, which in turn encourages condensation also on the inside of the wall. I'm not an expert so please don't think this is professional advice but this is what I have learned from watching my own house and seeing other peoples, and to me most problems are just obvious practical solutions. Big problem with render is once it comes off, bricks underneath are usually a mess so it's working out how to cover them without creating the same problem. I'd also add if you have a cavity wall then damp usually isn't an issue. This wall of mine is solid 9inch wall with no cavity, typical of Victorian houses. Hope that helps. Thanks for watching.

[@tamariderr]

@@POUSEaroundtheHOUSE Yeah makes good sense. Thanks a lot for replying and keep the vids coming!

[@TheAmazingSpiderGuy_99]

@@POUSEaroundtheHOUSE Hi, we have a cavity in our house but we’ve noticed a false wall near the door that is in the gap where air gets in has some tide marks (think that’s what they’re called) and paint is coming off the wall. Wasn’t an issue previously. Will the cavity protect against the rest? (we’ve seen no signs of damp for a year since it was fitted otherwise) also what should we do to stop that issue with the false wall? Thanks.

[@evski77]

Hello and thankyou so much for doing these videos! I'm trying to do the drain next to the house as you show, digging and part filling with shingle. I'll take the shingle up to two bricks below DPC but how deep would you recommend the shingle layer should be and would you first put anything down to stop the surrounding rubble mixing with it? Thank you in advance for any possible answer :)

[@POUSEaroundtheHOUSE]

I would do a few inches deep. If you're using perforated drain pipe like me then enough to cover that. You could use a weed membrane underneath before putting the shingle in. Hope that helps. Best of luck with it.

[@evski77]

Thanks so much for taking time to reply, I'm actually removing a row of block paving by the back wall as we speak, it's level with the DPC. I'm uncovering the first two bricks height easy, but it's getting harder below that, so hence my question, as I understand those two bricks below DPC are best left uncovered and breathing even once back filled with the shingle. I did wander if to put some sort of edging along the block paving, to prevent erosion of material and gradual sinking of the paving there? A builder friend has just had a look and told me I'm digging too deep, and too wide and why not just install aco drain at the height of paving (which would be at the height of DPC) but I'm confused as to how that would prevent the moisture from splash back at that height. I had no intention of installing any pipe as I don't believe water runs towards the house, but it is a west facing wall with a lot of wind driven rain. Plus I admit I wouldn't have a clue where it comes to pipes....

[@evski77]

Ps I didn't realise you installed a perforated pipe under the shingle.

[@POUSEaroundtheHOUSE]

@@evski77 yes. There are 3 parts to the video. If you watch them all it will make sense. Maybe not necessary to put pipe in, it was just belt and braces to drain away any groundwater that collected.

[@AutoFreak10]

could I ask what you do with the trench after ? I have the same problem as yourself and am going to dig it out. I was thinking of putting metal draining grates in but would this also make the splash back ?

[@POUSEaroundtheHOUSE]

Thanks for watching my video. I hope to upload a better quality video of the work I carried out following this video. Please feel free to subscribe to receive updates when I upload them.I have used perforated land drainage pipe in the base of the trench, which drains to my main sewer, and back filled it with gravel/chippings to cover and protect the pipe but not as high as path level. I was lucky that my main sewer drain runs along the same side of the house so I was able to break into it which made the job a bit easier. I'm also lucky that my path slopes away from the house so I have fitted a drain (as you mentioned) on that side to take the rain water away off the path. So the perforated pipe serves only to take away ground water build up after heavy rain (like a land drain).As a general rule you want your drain/path level a minimum of 6 inches below your interior floor level, but the lower you get it the better really, in order to avoid splash back and penetrating damp. Alternatively, if feasible you could remove the path and lower the whole thing? Another thing I did was drilled the wall through to behind my kitchen unit and added a vent. although this lets a bit of cold air behind the units inside, it provides ventilation to remove any moisture as often what appears to be 'damp' behind units, is usually condensation on the very cold solid brick walls. Mine has vastly improved now and appears to be drying out nicely.Hope this was useful. Good luck!

[@mmuhiuddin]

​@@POUSEaroundtheHOUSE Does this splash back problem seem to always happen at the back of the house and not the front, even though at the front of the house (in an old Victorian terrace) is usually pretty much path level? Also, if the back path was less that 6" below floorboards (or perhaps even level) but there was a grated drain running along the bottom of the wall and then a soft surface on the path (e.g., gravel or artificial grass) to reduce splash back, could that also prevent the walls saturating with water? Thanks for all the great vid's

[@POUSEaroundtheHOUSE]

@@mmuhiuddin I think soft surface helps in my opinion but also get the outside lower than the inside floor where possible. Oddly the back of my house is solid brick no cavity, but the front of my house has a large cavity, so I don't get problems out the front. The other issue is solid walls are always cold so damp is sometimes condensation and if plastered on the inside it seems to hold the moisture causing damp spots. I think all properties have different issues but you just have to try a few things and monitor them. Hope that helps.

[@mikegert2199]

Pouse, why have you done all that work when there are far quicker & cheaper solutions to doing the job? You have made a mountain out of a simple solution. No professional builder would ever do it your way - its a bizarre bit of making work. But you post it on youtube as though its the bees knees?

[@jemmawhite3143]

mike gert what's the faster and cheaper soulotion? if not this

[@POUSEaroundtheHOUSE]

Hi again Jemma, I assume he was referring to Damp proof injecting with chemicals. As I said I've never seen it work, that's not to say it doesn't but you only have to watch my videos to see how damp was above the injection damp proofing that someone had done prior to me buying the house. The fact is the path was to high outside and there is no cavity in the wall so moisture simply works its way through the wall. Mine is now bone dry inside. Make sure your outside ground level is a good 6 inches below your inside floor level. Also check to see if you have a cement render on your walls. If this is 'blown' or coming away, it will retain moisture behind it and make your walls damp and cold. Hope that helps.