Interior Fix for Bay Window Corners Damp

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Botty Fissure

Botty Fissure

New Member
Hello to everyone, I'm new here and ready for advice/a roasting.

As you'll see from the photos, we have had two damp areas, and these have been present for the past two years. We have now had the bay repointed outside, and a few weeks after that, I coated the brickwork with Stormdry. I wonder if a second coat is worth it but can't seem to find any info at all about two coats. So now I'm trying to fix the inside. I have 3 ideas and would really appreciate some advice on the best thing to do here.

So here are my ideas:

Clean all this brickwork off as best I can. Coat the brick in neat PVA. Fill it all in with sand and cement. Another coat of PVA. Do two coats of Thistle Multi Finish. Sand and then use a Toupret fine filler to clean it up and repeat as needed.

Clean all the brickwork as above. Cut some 9.5mm plasterboard and dot & dab it with standard Pink Grip—I'm guessing that stuff won't bridge damp due to its makeup. Fill the gap around the edge with ______? and mesh tape. Repeat as needed.

Paint the bricks with Safeguard Drybase. Fill with Hardwall—will it stick to the DPM?—and then finish with Multi Finish. And would I need any PVA at any point? To me, this method is a lot more desirable to carry out.

I'm a semi-keen DIY dude and can be pretty good when I put my mind to it. The nearest task I have done to this is fix up an old cracked and flaky bathroom ceiling. I realise that the rad will hamper me a lot in getting a decent finish on both sides.

What would you all suggest, please?

Much obliged! ✌️
 

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Monkey Boy said:
I reckon window is the problem
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Hi MB, Thanks for the reply. How so? If it was the window then surely there would be signs of damp on the brickwork, considering it's been hammering it down recently. That board has been off for weeks now. Cheers
 
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Hi Cockney,

Thanks very much for your reply.

I’ve added some images from outside. The sill cracks has been ground out and filled—it still needs painting. The silicone between the window trim and the sill has been redone with CT1, and the silicone around the windows has been checked. The corners have been repointed with a lime mix and painted with Stormdry a few weeks later. The building dates back to the 1880s.

What would you suggest as the best approach for fixing this up inside? The damp was slow and gradual, and although I’ve done everything I can to prevent moisture from coming in, I still want to create some kind of barrier inside to stop anything from reaching the surface. Oddly, the bricks don’t seem damp. There’s quite a bit of air coming in when I put my hand there, so maybe that caused the moisture?

Whatever I do, I assume I need to fill the gaps between the bricks with sand and cement to stop this. I’ve gathered a few ideas from the web, but I’m still unsure which is the best one for this particular problem.

Here’s what I’m currently thinking:

1. Fill the brickwork with sand and cement—maybe add SBR?
2. Paint that with Safeguard Drybase—possibly apply Blue Grit after?
3. A few coats of Multi Finish.
4. Sand and use a fine filler to smooth it out, as I won’t get it perfect on the first attempt near the radiator sides.

This building really takes a beating from the weather. It rained heavily last night, and it’s been frequent lately. However, nothing seems wet where I’ve cut the wall out—just draughty.

Can someone please help?

Cheers!✌️
 

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  • Interior Fix for Bay Window Corners Damp
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  • Interior Fix for Bay Window Corners Damp
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Right where the baypoles are.. Chances are its the bay roof if there is one but you should realise those areas where the windows join are hollow and if its a supporting bay of anykind those hollow baypoles should project through the cill onto the brickwork, which means even if the cill isnt one welded peice, there will be holes in it at those corners. get a hosepipe on the outside, start directing it at the lowest point of the cill mitre and have someone as a spotter on the inside, work upwards from there until you get ingress. That will be your issue.
 
Chris W said:
Right where the baypoles are.. Chances are its the bay roof if there is one but you should realise those areas where the windows join are hollow and if its a supporting bay of anykind those hollow baypoles should project through the cill onto the brickwork, which means even if the cill isnt one welded peice, there will be holes in it at those corners. get a hosepipe on the outside, start directing it at the lowest point of the cill mitre and have someone as a spotter on the inside, work upwards from there until you get ingress. That will be your issue.
Click to expand...
Hi Chris, Thanks for the reply. We (the three freeholders) have already spent the budget on the exterior work. We got done by a builder for £800 to repoint only parts of the exterior. The quote that came back too late - the guy we wanted to use - was the same money to repoint the whole of our level, including the baypoles and everything above it. All I'm asking is how I can fix the inside. All the exterior work is finished and the scaffolding is coming down. If you look at the original post you'll see the images for the interior work, which relate to the question asked. Thanks
 
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Botty Fissure said:
Hello to everyone, I'm new here and ready for advice/a roasting.

As you'll see from the photos, we have had two damp areas, and these have been present for the past two years. We have now had the bay repointed outside, and a few weeks after that, I coated the brickwork with Stormdry. I wonder if a second coat is worth it but can't seem to find any info at all about two coats. So now I'm trying to fix the inside. I have 3 ideas and would really appreciate some advice on the best thing to do here.

So here are my ideas:

Clean all this brickwork off as best I can. Coat the brick in neat PVA. Fill it all in with sand and cement. Another coat of PVA. Do two coats of Thistle Multi Finish. Sand and then use a Toupret fine filler to clean it up and repeat as needed.

Clean all the brickwork as above. Cut some 9.5mm plasterboard and dot & dab it with standard Pink Grip—I'm guessing that stuff won't bridge damp due to its makeup. Fill the gap around the edge with ______? and mesh tape. Repeat as needed.

Paint the bricks with Safeguard Drybase. Fill with Hardwall—will it stick to the DPM?—and then finish with Multi Finish. And would I need any PVA at any point? To me, this method is a lot more desirable to carry out.

I'm a semi-keen DIY dude and can be pretty good when I put my mind to it. The nearest task I have done to this is fix up an old cracked and flaky bathroom ceiling. I realise that the rad will hamper me a lot in getting a decent finish on both sides.

What would you all suggest, please?

Much obliged! ✌️
Click to expand...

Fotty Bissure would have been a better choice
 
Botty Fissure said:
Hi Chris, Thanks for the reply. We (the three freeholders) have already spent the budget on the exterior work. We got done by a builder for £800 to repoint only parts of the exterior. The quote that came back too late - the guy we wanted to use - was the same money to repoint the whole of our level, including the baypoles and everything above it. All I'm asking is how I can fix the inside. All the exterior work is finished and the scaffolding is coming down. If you look at the original post you'll see the images for the interior work, which relate to the question asked. Thanks
Click to expand...
thats ok then didnt see the brickwork outside. you can plaster it back up now, I'd probably take the rad off, knock the existing off and s+c it with some waterproofer cos I'm not a fan of gypsum backing on a solid 9" external wall but condensation might still cause an issue on the returns so you could point and tank the lot and dab some thin insulated board on or you could just squirt some diy foam into the gaps under the cill and gob it up with hardwall or you could just point it up and have it as a 'feature' or you could dri-coat it or limelite it or possibly even run the carpet up the walls that'll look nice or you could put the chrimbo tree there and hide it with tinsel as its nearly chrimbo or you could move the rad forwards and build a kind of window seat there so you can watch the neighbours or you could clad it with 3mm thick matchboarding like they did in the 90s or even sappelle sheet like they did in the 70's (my dad was a huge fan) no hang on, artex - always a winner (y)
 
ChrispyUK said:
Click to expand...

Chris W said:
thats ok then didnt see the brickwork outside. you can plaster it back up now, I'd probably take the rad off, knock the existing off and s+c it with some waterproofer cos I'm not a fan of gypsum backing on a solid 9" external wall but condensation might still cause an issue on the returns so you could point and tank the lot and dab some thin insulated board on or you could just squirt some diy foam into the gaps under the cill and gob it up with hardwall or you could just point it up and have it as a 'feature' or you could dri-coat it or limelite it or possibly even run the carpet up the walls that'll look nice or you could put the chrimbo tree there and hide it with tinsel as its nearly chrimbo or you could move the rad forwards and build a kind of window seat there so you can watch the neighbours or you could clad it with 3mm thick matchboarding like they did in the 90s or even sappelle sheet like they did in the 70's (my dad was a huge fan) no hang on, artex - always a winner (y)
Click to expand...

Nice tune, Chrispy. I've sorted it for now, as my Mrs was getting dark. But if I decide to go any further, I'll probably go for the carpet idea, Chris. I saw a nice piece of shag propped up against a wall in an alley down the road, the dogs love it. If I don’t do that, I might just fill it in with some sand, cement, dog piss, scratch that up, and then do a few coats of Multi Finish. The only bit I’m slightly in the fog about is the timing and need for water and/or PVA. There's no f***in’ way the rad is coming off. #fridgemagnets
 

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Botty Fissure said:
Nice tune, Chrispy. I've sorted it for now, as my Mrs was getting dark. But if I decide to go any further, I'll probably go for the carpet idea, Chris. I saw a nice piece of shag propped up against a wall in an alley down the road, the dogs love it. If I don’t do that, I might just fill it in with some sand, cement, dog piss, scratch that up, and then do a few coats of Multi Finish. The only bit I’m slightly in the fog about is the timing and need for water and/or PVA. There's no f***in’ way the rad is coming off. #fridgemagnets
Click to expand...
Fukin G** rad that is mate, you'd best call a real man to sort it out .
 
Chris W said:
thats ok then didnt see the brickwork outside. you can plaster it back up now, I'd probably take the rad off, knock the existing off and s+c it with some waterproofer cos I'm not a fan of gypsum backing on a solid 9" external wall but condensation might still cause an issue on the returns so you could point and tank the lot and dab some thin insulated board on or you could just squirt some diy foam into the gaps under the cill and gob it up with hardwall or you could just point it up and have it as a 'feature' or you could dri-coat it or limelite it or possibly even run the carpet up the walls that'll look nice or you could put the chrimbo tree there and hide it with tinsel as its nearly chrimbo or you could move the rad forwards and build a kind of window seat there so you can watch the neighbours or you could clad it with 3mm thick matchboarding like they did in the 90s or even sappelle sheet like they did in the 70's (my dad was a huge fan) no hang on, artex - always a winner (y)
Click to expand...
That's got Universal straight of the brick all over it mate, problem being is finding some plasterer that can do that, these fine days.
 
Chris W said:
you wont have time if you use the dog piss, any shitbrained plasterer will tell you it sets it off too quick..
Click to expand...
I wouldn't use the dog piss, Chris. I couldn't do my own wall like that. I'm gonna use holy water to ward off the lords vengeful weather.

All jokes aside, as this post has blown a bit off course.

If I'm going to fill this all out with sand and cement, with this in it.


Would it be advised to add SBR to the surface of the dry sand & cement before going over with the Multi Finish, or what would be best for such a wall that takes an exterior battering, pls?

That question is for anyone that cares to spread the knowledge.

Cheers!
 

Attachments

  • Interior Fix for Bay Window Corners Damp
    IMG_4442.jpg
    1.7 MB · Views: 13
  • Interior Fix for Bay Window Corners Damp
    IMG_4443.jpg
    1.8 MB · Views: 11
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