Rain penetrating walls - is lime render the only solution?

[Mickey]

Jackpoint that is what alot of properties are like here in Cornwall and now I know why!! No way our CO would allow that though...we are still doing battle with the horrific rain, currently 4 trug buckets, 1 tupperware and a dehumidifier in situ. Speaking to our stonemason tonight to see when he can come and repoint the inside ...we did indeed have a hollow void which had been washed out due to years of neglect to our building but he filled that with lime I am hoping that there are not more voids but he did say to me that once he raked out what remained of the inside pointing which was satruated and pretty much fell out he could get the handle of the raking out tool completely into the gaps left up to the hilt. I am not a religious woman but after the weather we have had I am praying hard repointing the inside works! If one more person suggests to me "Oh you just need to slap on some of that waterproof silicon stuff" I am going to lose it!

Mickey

 

[jackpoint]

Haha, I would like a quid for every suggestion of "waterproof silicon stuff". Currently emptying our poor dehumidifier twice a day...


So who around here wished for a warm winter :roll: :lol:

 

[stuwlam]

Speaking to our stonemason tonight to see when he can come and repoint the inside ...we did indeed have a hollow void which had been washed out due to years of neglect to our building but he filled that with lime I am hoping that there are not more voids but he did say to me that once he raked out what remained of the inside pointing which was saturated and pretty much fell out he could get the handle of the raking out tool completely into the gaps left up to the hilt.
Mickey

Sounds to me like your wall may have quite a few hollow areas, so perhaps ask your mason about filling it with lime grout. We did this this summer on a large very unstable rubble wall after repointing inside and out. Its now drying out gradually (7 tons of materials went into it) but the change in the internal climate of the rooms where this wall is located is astonishing. Even with only a scratch coat of lime plaster on the inside at the moment they are much warmer and drier. You can see it on my blog here - have a look at the posts for weeks 6 to 12 http://oldlawnsrenovate.blogspot.co.uk/2013/09/the-restoration-week-six.html

On the question of rain penetration through brick my money would be on dodgy pointing. Water can travel an enormous distance sideways and downward in a wall so the site of internal damp might bear no relation to the origin on the outside. We saw this for real when our stone wall was grouted - grout would appear out of pinholes in the pointing several metres away from where it was being poured into the wall and it would even appear in adjacent brick joints having tracked from the stone wall around the corner of the building into the brickwork! in one room it even tracked along a beam in the wall and finally dripped out of the ceiling about 4 metres INTO the room on the inside! If the house is going to be left as brick (assuming your Mrs wins the argument) then it'll probably benefit from extensive repointing anyway, so you may find that that solves the problem. Good luck!

 

[88v8]

Speaking to our stonemason tonight to see when he can come and repoint the inside ...we did indeed have a hollow void which had been washed out due to years of neglect to our building but he filled that with lime

Sounds to me like your wall may have quite a few hollow areas, so perhaps ask your mason about filling it with lime grout.

Interesting. Our walls here - coursed rubble, external cement pointing by PO, are and have been providentially dry on the inside. Even though there is no mortar as such between the stones, they were laid on a bed of clay which has dried out over the (400) years to such an extent that in places the wind whistles right through the 18" walls, or did before the internal lime pointing.
In essence, they are two walls, or at least two skins, with the interspace filled with nothing or nothing much. I had assumed that this 'cavity' was what kept the inner wall dry, and I must say that filling it would be the last thing I'd do, especially as the process is irreversible.

As to the OP's problem, first step I guess, complete hackout and repoint. If there is a dpc then you can repoint in cement if you don't mind the look, or perhaps that bastard mixture involving hydrated lime and white cement. If it doesn't work then hang tiles would be a good solution although you would lose that detailing around the windows. Not clay hangers, they're jolly heavy, but those pictured would be good.

Makes our ground-level dampness problems look relatively minor :shock:

Ivor

 

[jackpoint]

My God, you said the 'C*' word :shock: :lol:












*Cement

 

[Penners]

http://www.cliff-colman.net/Flanders&Swann.htm

 

[stuwlam]

Interesting. Our walls here - coursed rubble, external cement pointing by PO, are and have been providentially dry on the inside. Even though there is no mortar as such between the stones, they were laid on a bed of clay which has dried out over the (400) years to such an extent that in places the wind whistles right through the 18" walls, or did before the internal lime pointing.
In essence, they are two walls, or at least two skins, with the interspace filled with nothing or nothing much. I had assumed that this 'cavity' was what kept the inner wall dry, and I must say that filling it would be the last thing I'd do, especially as the process is irreversible.

Lime grouting in our case WAS the only feasible solution and since its a totally breathable lime mixture I have no worries whatsoever about filling the internal spaces in the wall. I suspect that 400 years ago the internal space in your wall (like ours) was filled with all kinds of cr*p which has long ago consolidated or been washed down to the base of the wall. The outer pointing in cement suggests that this wall was once upon a time full of holes on the outside which would have let in rain and that will have washed out the internal fill. Internally pointing to stop the wind doesn't give any strength to the wall. In our case what was left without the "core" material in the middle was a VERY unstable outer skin of stone which you could move by leaning on it once the render was removed and a very unstable internal skin held together only by plaster. Now its full of breathable lime and pinned outer to inner skin with stainless steel ties - its going nowhere and is good for another 400 years - and breathing like it should.

 

[Mickey]

Many thanks Stulam I have been an avid reader of your blog and totally agree with you on the application of lime grout, your building is looking great. Our bedroom gable has received some of this treatment already when our stonemason found a void during repointing. Sadly the mirror image living room gable is now leaking which it never did before we removed the cement smearing and pointing and replaced with lime, it's frustrating since I know we did the right thing but it has caused us more problems. Both problems occur over the 'head' of the windows where the wall is thinner anyway our walls according to our listing are/where! rubble filled. Problem is compounded by all of the plasterboard dry lining being foil backed which sends the water in all directions. On the upside the sun is out today in Cornwall.

 

[stuwlam]

Many thanks Stulam I have been an avid reader of your blog and totally agree with you on the application of lime grout, your building is looking great.

Thanks, we thnk so too