cavity wall insulation bristles

[Marco1976]

Hi,

I'd like the know how do cavity wall insulation firms insert cavity barriers between semi detached houses. Do they take a few bricks out and stick them in from there or is it done via loft space?

Our semi is rendered on three elevations so if they had to access the brickwork they would have to hack off some of the render.

thanks

 

[Nige F]

one or two out @ top + bottom of wall. May be access to cavity from your loft so minimum would be a hole @ the bottom of the wall

 

[JohnD]

what do you mean by

cavity barriers

 

[r896neo]

the crowd i use just need a 20mm hole on each level and pull a brush through that expands as its pulled.