Cavity closers and advice to my issue

[TimToos]

Hi all,

I am looking for some advice.

Having built my own house in 2018 (with help) I have an issue with mould and water around the windows and sills, especially in the bathrooms and kitchen (and bedrooms in a morning).

When I sealed up the cavity's around the windows and doors, I blocked up and cemented over. The issue now is that I have a massive cold bridge into the room.

The house is built from reclaimed stone with a breeze inner. When you feel around the window you can really feel the cold coming through as you get closer to the window.

What I am thinking of is every time I decorate a room is to remove the plaster board and the bridging blocks and then replace with proper insulated cavity closers. Thats all I can think of.

Obviously this is really annoying that I have done this. Is there any advice?

TIA

 

[Swwils]

This is a classic cold bridge as your describe, it must be very bad to produce these effects.

More ventilation will help alot, but may not solve the issue.

How far set back are the windows? If they are very close to the outer leaf face then you likely have totally bridged the reveal aswell, regardless of any close you retrofit.

It could also be solved by insulated plasterboard to reveals, but you might not have the depth on the frames to accommodate this before you end up with finishes over the glazing.

It's possible you have some direct air ingress from the outside, what do the outside joints look like?

 

[TimToos]

The total wall thickness from outside to inside is 18" (460mm). This is the stone, air cavity, insulation and block.
The windows are set back from the outside 50/60mm leaving a window reveal of roughly 300mm. The windows are PVC double glazed. To be honest the sealing looks good but I wouldnt bet its the best as we have had issues with the installer.
There's not enough window frame to accommodate insulated board unfortunately.
Do you this can be sorted?

 

[Swwils]

Your suggestion of removing the offending blocks and inserting a closer (many can be retrofitted) should make a massive difference.

Make sure the blocks were not required for whatever reason, your architect should provide the intended detail.

 

[TimToos]

We just put them in. At the time I felt we were making the house much stronger. Oh well, live and learn.
I think the best thing is to pull the plaster off and remove the blocks each time I decorate a room. In the meantime keep wiping them down to remove moisture, retreating and painting them each year.

 

[TimToos]

Many thanks for your advice. Would you agree with changing them like this or would you just do the lot in one go in the summer?

 

[Swwils]

Depends on what you would like to do, I suppose you will get quite good at it.

You do need to check the detail, the block might have substituted the additional wall ties around openings.

 

[TimToos]

Will do. Thanks very much

 

[Old Salt]

Pick the worst room first and see how it goes. Lots to be said for getting it over and done with once the weather improves, and think how cosy you will be in Christmas 2022.

 

[TimToos]

Just glad I can sort it. Had a few bed time thoughts recently on what the issue is and best way to sort.

 

[Swwils]

At least you don't also need to move the windows, that's what I'm facing!

 

[TimToos]

Oh no, really? Thats a much bigger job. What issues are you having?

 

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