爱男馆你的私人小站 爱男馆你的私人小站 ,乡下美母在线观看 乡下美母在线观看 ,青春娱乐视频分类官网 青春娱乐视频分类官网

Damp patches appearing on walls

Discussion in 'Just Talk' started by MJG1989, Dec 21, 2020.

  1. MJG1989

    MJG1989 New Member

    Hi - first time poster here. Appreciate any help or advice people can give :)

    We've moved to a new house last week. It is semi-detached, built in 1910. It is brick with a white paint/coating of some sort. Over the course of the week we've painted most of the walls upstairs and down. In the front room (which has a bay window and fireplace) there are two dark patches that have appeared on the walls.

    The first came around 24 hrs after painting. It is slightly colder to the touch and although the wall isn't wet, the paint feels slightly chalky compared to the dry paint on the rest of the wall. The patch is on an external wall, and on the other side there is a plant growing up the outside of the building. The dark patch is around halfway up the wall and there is a pattern to it that roughly seems to match the structure of the branches of the plant.

    The second patch appeared around 48 hrs after painting. It is lower down the wall, around an inch above the skirting board. However, this is on an internal wall, with the other side of the wall being under the stairs. Poking around under the stairs I've since found that under the wall between floorboard and skirting board there was a load of carpet underlay that had been shoved in. When this was removed a clear draft blew through, so I'm assuming it was shoved in as a slapdash way to prevent the draft.

    Both patches are roughly similar in size - around 30-40 cm wide.

    The floorboards and skirting boards are dry beneath both.

    Based on what I've read online, I think the problem may be condensation forming on the walls and then not having adequate opportunity to evaporate due to lack of ventilation (caused by the plant and underlay squashed under the wall) in the affected areas. Would other posters agree that is likely, or could there be another cause.

    We also noticed when painting upstairs that the corners of walls on the outside of the house took forever to try or didn't dry on their own. Again, I think this indicates moisture settling in cold spots and preventing paint from drying. It has rained a lot but we've not seen any evidence of water coming down the corners of the house from the guttering. The wet corners haven't re-appeared since drying.

    The house was unoccupied for several months before we moved and there aren't ventilation grills above the windows, except the bathroom.

    I've tried opening windows and keeping the temperature steady since the dark patches appeared. No further patches have emerged in the 4-5 days since and the existing dark patches haven't changed. They may have decreased slightly but hard to really be sure.

    I suppose my questions are: Is my theory about the condensation and lack of ventilation plausible and of not what is likely to be causing this issue? Could there be a more serious problem (e.g rising damp)? Should we get an expert in? How should we address the dark patches that have appeared on the walls?

    Any advice is welcome. Thanks in advance to anyone able to help.
  2. Joe the Plumber

    Joe the Plumber Screwfix Select

    "Rising damp" is a chemical salesman's bulls**t, designed to frighten the unsuspecting into having unnecessary work done to their house. Any 'expert' in it
    is a cowboy. There's nothing else you need to know about that.

    However, everything you do need to know about damp is here:


    With any dampness issue, all you need to do is find and eliminate the source of the water and the problem will be solved.

    I'd lose the plant. Anything growing up the side of a building is asking for trouble. If it's got a coating on the outside of the wall, check
    if that's got cracks in it which could allow water in but not back out again. Bricks like to breathe, so coating them
    in anything is never a good idea.
  3. kitfit1

    kitfit1 Screwfix Select

    @Joe the Plumber has given you very good advice. One thing to always keep in mind with a house of your age and type is that if it has a cavity at all, it will only be 12.5mm/25mm at most. Water ingress from the outside is par for the course with this type of construction and as Joe has said, coating the outer bricks in render or paint only hides and delays the issue, it will never stop it. Find where water is getting in and then eliminate the source, ultimately that is the only answer.
  4. Bob Rathbone

    Bob Rathbone Screwfix Select

    Could be interstitial condensation, as the warm dam air penetrates the brickwork from inside to out, the temperature drops and at some pint the dew point will be reached and condensation will occur within the building fabric. This will eventually show itself by a wet patch inside. Take steps to eliminate sources of moisture in the air, fit a cooker hood venting to outside, an extractor fan over the bath or shower and perhaps a de humidifier on the landing.
  5. MJG1989

    MJG1989 New Member

    Thanks all. That is helpful advice.

    The damp patch that appeared backs onto the cupboard under the stairs. The stairs are directly in front of the front door where it gets cold so it makes sense that this is a cool spot where condensation is forming as a result. We'll look at fitting additional ventilation measures and keeping the temperature steady.

    I've also done some additional exploratory work, lifting a floorboard under the stairs and pulling back the plaster. The brickwork behind seems fine and there is no sign of moisture under the floorboards. The condensation seems to be forming above this on on the wall. There are several layers of old paint (which have now started to lake away due to the dampness). Based on the info on the above link, I'm thinking that another factor that may be aggravating the situation is that the old paints are restricting moisture from escaping as well.

    Something we've also noticed is that the the driveway, which runs in front of and along the side of the house, slopes toward the house in one place, causing water to puddle at the foot of the building. This happens to be right at the roots of the plant on the outside of the building, which I mentioned above. Clearly we'll need to address this as I can't imagine it is doing the foundations any good, and could be contributing to moisture getting into the building.

    I should add, it looks like injection damp proof was put into the walls by the previous owner. Reading the HH info posted above, it seems this was useless and possibly damaging.
    MJG1989,爱男馆你的私人小站 爱男馆你的私人小站 ,乡下美母在线观看 乡下美母在线观看 ,青春娱乐视频分类官网 青春娱乐视频分类官网 Dec 23, 2020
    Joe the Plumber likes this.
  6. koolpc

    koolpc Screwfix Select

    Plus, if the house has been unoccupied for a long time and you move in and turn heating on, any dampness in the walls may be being drawn out.
  7. MJG1989

    MJG1989 New Member

    Thanks @koolpc yes, I expect that is also part of the problem based on what I can see on the HH site.

    Any ideas how long the drying process might take once any other issues are resolved?
  8. MJG1989

    MJG1989 New Member

    Hi again - thanks for your previous input. Much appreciated.

    Some good news and some bad. The wall under the stairs appears to be drying. There is still no sign of moisture coming in at that point, so I think it is condensation/moisture in the walls as above. Plan is to fit some additional ventilation and keep an eye on those problems spots for signs of condensation.

    On lifting the carpet in the front room we've also seen some signs of mould on the floorboards. This was beneath a blue plastic membrane. I've since lifted a floorboard and found the soil underneath is slightly moist. Nothing major but not totally dry. Seems that excess moisture is evaporating up and getting 'stuck' under the plastic and can't escpape.

    On the exterior wall where this occurs there is some sign of water build-up during heavy rain.

    I think the drainage channel around the outside is inadequate, and there is only a single air brick to allow moisture under the floor to evaporate.

    I'm thinking to get someone in to look at the drainage, and measures that could be taken to channel moisture away from the building on the driveway. Plus possibly fit some new air bricks.

    Any further advice very welcome!

    And of course, happy Christmas and new year :)
  9. Mr Rusty

    Mr Rusty Screwfix Select

    Not true - our 1902 has 2" cavities. Drawn on the original architects plans as 11" walls (as opposed to 9" solids). It seems up here in darkest lancashire we were ahead of the trend:D
  10. koolpc

    koolpc Screwfix Select

    Is that when they started to implement cavity wall construction? Did they use wall ties too in those days?
  11. Mr Rusty

    Mr Rusty Screwfix Select

    爱男馆你的私人小站 爱男馆你的私人小站 ,乡下美母在线观看 乡下美母在线观看 ,青春娱乐视频分类官网 青春娱乐视频分类官网
    Yes we have thick wire ties. They failed on the accrington brick front face wall and we had it rebuilt a few years ago. The rest are good, although we added a few new stainless ties fixed with resin during our refurb. around windows just for good measure.
  12. kitfit1

    kitfit1 Screwfix Select

    爱男馆你的私人小站 爱男馆你的私人小站 ,乡下美母在线观看 乡下美母在线观看 ,青春娱乐视频分类官网 青春娱乐视频分类官网
    Being tup norf, you would have needed it before us suverners :D
  13. toolz

    toolz Member

    What is "the plant"? Ivy? Wisteria? I'd happily get rid of ivy but not a wisteria!
  14. MJG1989

    MJG1989 New Member

    I think the plant is a honeysuckle

Share This Page

爱男馆你的私人小站 爱男馆你的私人小站 ,乡下美母在线观看 乡下美母在线观看 ,青春娱乐视频分类官网 青春娱乐视频分类官网