Damp PROBLEM in bay window and surrounding area

Pjsimpson

New Member
I have a damp problem on and around the bay window at the front of my house. I've had a damp survey done which has flagged high exterior ground levels - which I'm getting reduced - I'm also going to install three new air vents as all have been concreted closed.

I've removed all of the interior plaster and previously installed cement based tanking due to there still being a damp problem with it in place - I reckoned It would be no harm removing and replacing, I just needed to see what situation I was dealing with, if anything at all above the dpc.

The thing is now I need to put something back in its place, I don't know whether to use another cement based DPC then have it rendered and plastered, or use an egg box plastic DPC and then Dot and Dab over the top.

I was thinking that it might work if I use a physical DPC and then Dot and Dab with a polystyrene backed plasterboard for added insulation. I have read extensively about all of the options available, my issue is that the bay has crumbly brickwork - therefore using a slurry would be best to hold it together and to waterproof - but then the wall will just be holding water and eventually will have to be fixed again, something I really can't be bothered dealing with in the future.

A physical DPC therefore sounds like the right way to go, but because the wall is slightly crumbly I don't know whether drilling hundreds of holes into it will help the situation! I need advice from somebody who has dealt with this sort of situation before and had a good outcome, any advice or experience would be welcomed.
 

Stevieo

Royal Spin Doctor
I have a damp problem on and around the bay window at the front of my house. I've had a damp survey done which has flagged high exterior ground levels - which I'm getting reduced - I'm also going to install three new air vents as all have been concreted closed.

I've removed all of the interior plaster and previously installed cement based tanking due to there still being a damp problem with it in place - I reckoned It would be no harm removing and replacing, I just needed to see what situation I was dealing with, if anything at all above the dpc.

The thing is now I need to put something back in its place, I don't know whether to use another cement based DPC then have it rendered and plastered, or use an egg box plastic DPC and then Dot and Dab over the top.

I was thinking that it might work if I use a physical DPC and then Dot and Dab with a polystyrene backed plasterboard for added insulation. I have read extensively about all of the options available, my issue is that the bay has crumbly brickwork - therefore using a slurry would be best to hold it together and to waterproof - but then the wall will just be holding water and eventually will have to be fixed again, something I really can't be bothered dealing with in the future.

A physical DPC therefore sounds like the right way to go, but because the wall is slightly crumbly I don't know whether drilling hundreds of holes into it will help the situation! I need advice from somebody who has dealt with this sort of situation before and had a good outcome, any advice or experience would be welcomed.
@dampworks
 
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