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Done all checks but still have some penetrating damp to third floor flat. Researched external barriers such as storm guard and storm dry which claim to still allow the wall to breathe. Does anyone know how effective these sort of barriers are ?
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Done all checks but still have some penetrating damp to third floor flat. Researched external barriers such as storm guard and storm dry which claim to still allow the wall to breathe. Does anyone know how effective these sort of barriers are ?
We bought a new house situated about 800 ft above sea level in the Pennines. The horizontal rain we got there saturated the outer wall bricks and in places we had damp patches where water crept across the wall-ties.
The builder applied silicone-based waterproofing fluid which was effective for the 4 years we lived there (yes, taking bricks out and cleaning/altering the wall ties is the proper fix for the problem)
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We bought a new house situated about 800 ft above sea level in the Pennines. The horizontal rain we got there saturated the outer wall bricks and in places we had damp patches where water crept across the wall-ties.
The builder applied silicone-based waterproofing fluid which was effective for the 4 years we lived there (yes, taking bricks out and cleaning/altering the wall ties is the proper fix for the problem)
Bad workmanship normally to blame in these situations. Lots of mortar dropped into the cavity as the wall increases in height which sticks to the ties (and faces of the stone if built in Peak Park approved methods).
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Thank you for these two helpful replies. The forum has never let me down !
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Do the checks include drilling into the cavity and using an endoscope?
Damp at third floor suggests cavity problems. Do you have cavity wall insulation?
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It is random stone , rubble filled. Victorian converted.
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As its solid walls it could be water from roof level - water getting behind soffits, guttering etc. and flowing into the cracks in mortar etc and into the rubble.
How the internal walls are treated is also important - if the walls can't breath they will trap moisture.
Plenty of info here:
www.heritage-house.org/
It would be worth getting a specialist building surveyor (not a damp proof company who just want to sell products) to have a good look.
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Thanks for this. Link is especially appreciated. The website is a mine of information.
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From reading the posts so far it seems that you have solid walls with an outer skin of stonework. On the 3rd floor you have two possible causes. Wind driven rain coiming straight at the wall will penetrate eventually. If the pointing and stone are on good condition there is little to be done apart from trying a breathable coating. However the weather has to be quite extreme for an extended period to penetrate fully into a solid wall of at least 12 inch thickness. The two most likely causes are the bottom three courses of slate, which are directly above the wall or the wind is blowing the rainwater over the guttering and into the wall. Check the slates for damage and adequate overlap. Second cause is that slate roofs generally do not have sarking or underfelt which bridges the gap between the bottom edge of the slate and the centre of the gutter. As the water spills from the slate and before it lands in the gutter the wind can blow it against tthe wall. No sarking, no protection from this problem. It is fairly easy the install a flashing, which can be inserted under the slate and finished in the guttering. Lead is best but there other materials which will do the job, including roofing felt. I would try this first. At least then you can be sure the water is going into the gutter as intended and not down the wall. If the damp still persists when the rain is wind driven against the wall, then consider the expensive coatings. Hope it helps.
Concrete
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I assume you have gone out in heavy rain and watched the wall and roof? I had a blocked gutter, and when the gutter filled up, water overflowed, and curled back onto the wall, soaking it. Not sure how water can curl round, maybe some surface tension effect.
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I assume you have gone out in heavy rain and watched the wall and roof? I had a blocked gutter, and when the gutter filled up, water overflowed, and curled back onto the wall, soaking it. Not sure how water can curl round, maybe some surface tension effect.
I have seen this too. Guttering usually has a fall towards the downpipe, but if the facia is not plumb the guttering may have a bias one way or the other. In other words it is lower on one side than the other. Difficult ot spot, even up close unless there is standing water in the gutter. Impossible to see from below. You may even need a spiriy level to determine which way the bias is. If it towards the wall, then a full gutter with more water coming off the roof will overflow also a bit of wind and the water can be lapped over the gutter edge onto the wall. You can only spot it when it rains hard. Not easy. Worth checking when the weather is good.
Cheers Concrete
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I was working in my modern brick built garage one night with a gale blowing heavy rain onto the gable end wall of the garage. I looked up and that whole wall was literally running with water - never seen anything like it! It wasn't coming in through the roof or under the roof, it was actually coming through the bricks.
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The outer skin of bricks on my 1970's house allows daylight through never mind water. And people wonder why they have damp problems after having cavity wall insulation installed.
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I was working in my modern brick built garage one night with a gale blowing heavy rain onto the gable end wall of the garage. I looked up and that whole wall was literally running with water - never seen anything like it! It wasn't coming in through the roof or under the roof, it was actually coming through the bricks.
I’ve seen that too. My 1969 built garage has a single skin wall, and water has run down the inside after penetrating. I guess the brick gets saturated first, then water runs down the inside.
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Luckily we don't get such severe weather often. Cavity walls in general are good at keeping water away from the inner skin. If water penetrates the bricks and mortar then it runs down the cavity. Cavities should have drain points built in, but not always, but the water usually drains away quite well. A period of milder dry weather afterwards and the brickwork can dry out. It can cycle like this for many years. As for cavity insulation. A detailed survey should be done first to examine the exterior brickwork and the cavity to see if they are suitable to be filled with insulation. Not only will some insulation transmit water through to the inner skin, but also wet insulation is useless because it loses its ability to insulate. Modern new builds incorporate insulation boards or battens in the cavity and they are held against the inner skin with securing clips at the wall ties.. That way you get the insulation and the cavity protection against water. perenial problem keeping buildings in a good state of repair. Pays dividends in the end.
Cheers Concrete
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