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    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    I had an issue with driving rain hitting a gable wall and coming through to the plaster work.

    Brick built 1930s cavity wall house. Had insulation blown in during the last 6 yrs.

    Last time I thought the issue was an air brick allowing water in, so I cemented this up and no issues until last week. The brick was located to the left of the first floor hall window. No use for it anymore.

    I will load some pics tonight but thought I would start the thread.

    The water had entered a slightly different place this time. It is directly over the lintel of the hall 1st floor window. The water has tracked down the side of the window as well. There is another patch as you go down the stairs and this looks like it is around the top of the storage cupboard which is built into the gable under the stairs. There is a third patch close to the ground floor window at the bottom of the stairs.

    So I have 3 distinct areas where I think water is getting in.

    Now I had this wall repointed 5 yrs ago and I realise now it wasn’t done that well. The guy was basically ripping out only 10mm with his disk. I can see a lot of vertical perps need redoing.

    I need to check the wall more closely with my ladder but just haven’t had time to do this yet.

    So my thoughts are it’s the pointing. Also will there be a damp proof course above the window where a lot of water damage is happening? Could I retro fit some weep vents to allow water out?
    •  
      CommentAuthordjh
    • CommentTimeFeb 24th 2020
     
    Posted By: marsadaySo my thoughts are it’s the pointing.

    Unless there's a path directly from the roof or guttering?

    Could I retro fit some weep vents to allow water out?

    I would guess so, but others will have more expert views. I do think it would be worth drilling a test hole just above the lintel to see how much water comes out.

    Oh and I can recommend StormDry, although to be fair I've only used it indoors in showers.
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020 edited
     
    I dont think it is the roof, but i do need to get on the ladder. I will maybe do a pilot hole.

    Will look at storm dry, but if this is a brick sealer i have heard these are not the best products to use.

    I will see if these photos load. This photo = top of stairs.
      internal window.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    this photo lower down stairs
      lower stairs.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020 edited
     
    this photo bottom of stairs by window
      bottom stairs.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    external window with leak above
      external 1.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    same window looking more upwards
      external 2.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    close up of downstairs window lintel top where the damp patch is on the external right side just above lintel
      external 3.JPG
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    internal attic shot. Roof in good condition and walls dry inside the attic space
      internal roof.JPG
    • CommentAuthorCWatters
    • CommentTimeFeb 24th 2020
     
    I'm thinking the leak is at some height above the first floor window and it's running down inside to the cavity tray/DPC above the window. Then across the insulation to the inner leaf. The cavity tray should slope down to the outside which accounts for the damp patch being a bit higher up on the inside than where the cavity tray appears on the outside.

    Normally with an empty cavity there would be weep holes just above the cavity tray to let it escape. Not sure if they are still recommended with a cavity full of blown insulation.

    What type of insulation is it?

    Aside: I have to travel over next few days so may not get time to follow this up.
    • CommentAuthormarsaday
    • CommentTimeFeb 24th 2020
     
    It’s the blown soft fibres I think

    If the pointing is rubbish higher up it might be that.

    Or I wonder if the edging of the tile roof has eroded and so rain drives in front here and then tracks down into the cavity.

    Hopefully I can get up there later this week to have a look and I might get some more photos
    • CommentAuthorphiledge
    • CommentTimeFeb 25th 2020
     
    Theres only a fairly small area of exposed gable above the stair landing window so you would need a fair bit of very localised penetration to get enough water in for it to run down to midway up the stairs. Im not sure where the third window is as you say its "bottom of the stairs" but there seems to be a wall where the stairs would finish??

    As the landing window is under the lower section of the gable roof, thats where there will be more water running over the roof covering. If youre able to access the roof my suggestion would be to check the roof covering along the lower half of the verge. A cracked, damaged or missing slate in this area could allow water to run straight into the top of the cavity

    As far as cavity trays over lintels are concerned, Im not sure they were fitted to houses of that era??
    • CommentAuthorGreenPaddy
    • CommentTimeFeb 25th 2020
     
    My theory would be that the gable is generally letting water through, and shows itself where there is a bridge in the cavity.

    The damp is above the lintel, ideal bridge, and not condensation from within, as that would tend to be the shape of the lintel itself.

    The high internal leaf is dry, so I'm thinking not coming from above, or at least not pouring down the cavity face of the internal leaf.

    Doesn't take much water at all, to show up as a stain internally, so doesn't need to be a huge leak.

    I'm with djh on this one. Get in there, do a bit of drilling/poking about. I might even take a brick out at the offending areas. There's no better certainty than getting a look inside...but it is good fun guessing.
    • CommentAuthordickster
    • CommentTimeFeb 25th 2020
     
    Outer skin gradually gets soaked to 100% wetness in prolonged periods of wet driven rain. Then for every drop of water on outside, a drop of water forms on inside, would normally run down ventilated cavity and eventually disperse/evaporate. Now bridging across insulation.

    I have this problem on old properties that I manage, though without the insulation. Damp appears at bottom of cavities on inside (no lead trays), where cavity meets solid ground floor wall and/or above windows (again no trays).

    We coat outer skin with silicon waterproofer with seemingly no ill effects. Pointing all good.

    Just old age and increased porosity of outer skin, which should act as a raincoat over inner skin.
    • CommentAuthormarsaday
    • CommentTimeFeb 25th 2020
     
    Thanks all for the comments. All useful stuff.

    I am there tomorrow with my big ladder so will be able to inspect the roof and take some photos.

    Dickster's comment make sense.

    I want to see the pointing though close up. If it has failed (which i have seen lower down it has) then my first job is to repoint this gable. I have my own tower so not an expensive job in terms of money outlay, just time.
    • CommentAuthorrevor
    • CommentTimeFeb 26th 2020
     
    I guess you are in a fairly exposed area and the wind has driven the rain into the cavity . The problem of filling cavities particularly in an exposed district is than prior to filling any moisture inside the cavity would evaporate with the ventilation. The mortar on the wall ties will hold moisture and will track through to the inside via the wall tie. When we were building there were numerous reports in our local paper of houses becoming damp after filling with insulation done for free by the energy companies who had been threatened with fines if they did not use profits to improve the insulation in homes. However my previous house in a sheltered urban area was filled with insulation and that was not an issue and neither was my MIL's house. Here my architect told me they had to remove the outer skin of a property to remove the insulation and if one was to build a brick faced house here BC insist on a 75 MM clear cavity. That no doubt does not make good reading so I hope repointing will solve the issue but I suspect the bricks are porous to some extent anyway.
    Just a thought that might be worth considering and would solve your issue and that is to batten out the wall and add a rain-screen cladding which could be timber or cement based boards. You seem to have some room under the verge. Around the windows would need some thought but not unsurmountable and creatively done could give your house quite a facelift. Pointing is very labour intensive so the cost of this would go quite a way towards my suggested solution.
    • CommentAuthorKenny_M
    • CommentTimeFeb 26th 2020
     
    I also have an old house, although sandstone and whinstone, lime pointed walls, rather than brick. Last weekend I also had water ingress, some staining in an upstairs south/west facing room, and a pool of water on the fireplace hearth in the same room.

    A significant amount of water was coming down the stack, which is capped, but it coming down the stack doesn't completely explain where the staining is.

    I'm holding off on doing anything for the moment to see if I get a repeat. Not sure where you are, but the wind and rain we had here at the weekend was biblical. Dickster makes a good point about saturation. Not sure whether it is that in my case, or the combination of wind and excess rain, driving water in directions it wouldn't normally go.

    If you had the same levels of weather it might be an idea not to jump in and spend too much time and money and time in case it is a one off. Obviously if there is pointing or other work that obviously needs done then there is no point in ignoring it, but in my case I can't see any issues, and we've had more 'normal' heavy rain since and no repeat so far.
    • CommentAuthormarsaday
    • CommentTimeFeb 26th 2020
     
    We are urban, but this gable does get the weather more than the front and back.

    I have been up the ladder today and a lot of the perp joints have not been done very well and so i have quite a few holes. I am going to do the pointing myself so the cost is about £20-£50 depening on the amount i rip out. I have my grider with discs and own scaffold tower, so just my time. I wont be doing the whole area, but i think all in all it will be 2 days work.

    The roof is good, so no issues with water tracking down from here.
    • CommentAuthormarsaday
    • CommentTimeFeb 26th 2020
     
    <blockquote><cite>Posted By: Kenny_M</cite>I also have an old house, although sandstone and whinstone, lime pointed walls, rather than brick. Last weekend I also had water ingress, some staining in an upstairs south/west facing room, and a pool of water on the fireplace hearth in the same room.

    A significant amount of water was coming down the stack, which is capped, but it coming down the stack doesn't completely explain where the staining is.

    I'm holding off on doing anything for the moment to see if I get a repeat. Not sure where you are, but the wind and rain we had here at the weekend was biblical. Dickster makes a good point about saturation. Not sure whether it is that in my case, or the combination of wind and excess rain, driving water in directions it wouldn't normally go.

    If you had the same levels of weather it might be an idea not to jump in and spend too much time and money and time in case it is a one off. Obviously if there is pointing or other work that obviously needs done then there is no point in ignoring it, but in my case I can't see any issues, and we've had more 'normal' heavy rain since and no repeat so far.</blockquote>

    There is a hole somewhere. The wind pushing the rain in odd directions has exposed this. Hope you get on top of it eventually.
    • CommentAuthorCWatters
    • CommentTimeFeb 26th 2020
     
    Posted By: marsadayIt’s the blown soft fibres I think


    There may not actually be a leak. It's known that cavity wall insulation can cause water to bridge the cavity. Installers are meant to tell owners if they believe the wall is unsuitable for cavity wall insulation...

    https://www.which.co.uk/reviews/insulation/article/cavity-wall-insulation/cavity-wall-insulation-damp-problems


    One of the contraindications is exposure to wind driven rain. I believe blown fiber is more susceptible to this than the coated bead type but not sure I can prove it with references.

    I think fixing any bad pointing would be a good move. If no other source of leaks can be found then some sort of sealer may help as others have suggested. Even rendering in summer might be worth considering.

    There is a whole industry set up to remove cavity wall insulation that has got wet and is causing problems but probably no need to go that far without further evidence of a problem.

    https://www.google.com/search?q=cavity+wall+insulation+removal&oq=cavity+wall+insulation+removal&aqs=chrome..69i57j0l3.13756j0j8&client=tablet-android-pega&sourceid=chrome-mobile&ie=UTF-8
    • CommentAuthorCWatters
    • CommentTimeFeb 26th 2020
     
    PS some bricks are remarkable porous. I once filled a bucket with as many bricks as I could, then filled it up to the top with water. They fizzed and popped and a few hours later all the water had soaked into the bricks and dissapeared. These were brand new bricks for our house.
    • CommentAuthorKenny_M
    • CommentTimeFeb 27th 2020
     
    Posted By: marsadayThere is a hole somewhere. The wind pushing the rain in odd directions has exposed this. Hope you get on top of it eventually.


    I agree that there is a hole, I am just saying that if its only this rare combination of weather that exposes it then it might not be worth the effort to resolve it. It could have been the ventilation on the cap, or the one chimney that is cowled and in occasional use taking in water and it transferring through on the inside. Worth keeping an eye on though.
    • CommentAuthormarsaday
    • CommentTimeFeb 28th 2020
     
    Yes the top capping maybe cracked. I had this on a house and it massively stained the wall as it broke through the roof in the attic (converted).

    I thought it was going to be the flashings, but when i got up there i could see a largish crack in the capping area. So just chipped away the loose stuff and refilled with cement. Been fine ever since.
    • CommentAuthorbxman
    • CommentTimeFeb 29th 2020
     
    If you are lucky and Energy Company Obligation (ECO) money was involved with the CWI

    you could possibly have financial help with removing it .
    • CommentAuthormarsaday
    • CommentTimeMar 5th 2020
     
    Been on the wall yesterday. The mix used to do the pointing is far to weak and not deep enough. I have ripped out some sections where i think water was getting in. Fingers crossed this will fix it. Longer term i will need to redo this full wall i think.

    My mistake when i renovated this house in 2015 was to leave the pointing to a local labourer. He said he could do pointing and i let him get on with it, while i worked away inside. I can see now the ganga affected his thinking as he was smoking all day practically !
    • CommentAuthorbxman
    • CommentTimeMar 5th 2020
     
    before you make the pointing material to strong please take some advise first in that connection .
  1.  
    marsaday - If you are going to repoint a high proportion of the wall putting on EWI may be just as quick and if the eaves restricts thickness even 5 cm will make quite a difference.
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