External wall insulation on solid wall & cavity wall insulation on cavity gable walls

[dazzler9000]

Hi everyone. The main walls in my house are solid and need to have external wall insulation applied. I'm contemplating applying the foam insulation myself, as it looks like a DIY job, and I see there are some training courses available at reasonable prices. I'd then get in a pro to do the rendering.

I've been told by a couple of people that I'd need to get cavity wall insulation installed for the gable ends. This makes sense, but I don't know if it's necessary? I've spent a fair amount of time researching it, and I only see negativity on the subject. I appreciate that's how reviews tend to be, but all I keep reading is that the cavity needs to be left empty.

I'd appreciate the thoughts of other forum members/pros.

 

[Wayners]

Have you watched skillbuilder on YouTube regarding insulation.
Also the cork insulation that's come on the market looks an interesting product. They say it's better inside than out.
I don't know enough to advise you.

 

[^woody^]

There is nothing wrong with cavity wall insulation that is done correctly. This includes the cavity suitability assessment, along with the wall general condition. There are lots of tick-tockers who know jack about it.

For EWI or CWI, be aware of possible condensation/mould issues and you would normally need to assess the house ventilation and ensure it is suitable else adapt it. There is specific detailing required for EWI at floor level, openings and roof level, and these need to be done correctly.

Either requires building regulations, EWI may require planning permission and there may be certification issues when you come to sell if you DIY. Also check with your insurer particularly for EWI.

 

[dazzler9000]

Have you watched skillbuilder on YouTube regarding insulation.
Also the cork insulation that's come on the market looks an interesting product. They say it's better inside than out.
I don't know enough to advise you.

Hi, apologies for the late reply. Yes, I've seen it and various others, hence me contemplating the DIY route, it really doesn't look that difficult.

I've also seen the cork render, but again, I'm not sure about it, to know if it's a proven solution.

 

[dazzler9000]

There is nothing wrong with cavity wall insulation that is done correctly. This includes the cavity suitability assessment, along with the wall general condition. There are lots of tick-tockers who know jack about it.

For EWI or CWI, be aware of possible condensation/mould issues and you would normally need to assess the house ventilation and ensure it is suitable else adapt it. There is specific detailing required for EWI at floor level, openings and roof level, and these need to be done correctly.

Either requires building regulations, EWI may require planning permission and there may be certification issues when you come to sell if you DIY. Also check with your insurer particularly for EWI.

Thanks Woody, I've heard mixed views on CWI, but most negative. I may get somebody out for a survey.

It's crazy that to improve the thermal properties or my house, I need to ask for permission. How do I even start that process?

As mentioned, my plan was to CWI the gable ends and over the garage and then clad the brick with the slate that I'd used in my porch. Can I assume I'd definitely need planning for this?

My concern is that if the CWI does cause issues, there would be no way to rectify as id covered it with slate....

I'm aware of the ventilation issues that may arise as my house is already very wet.... Ideally I'd like to get MVHR, but I don't have an airtight house, so I don't know if ai could even get that installed....