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harry harry is offline
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Default Bricking up an external door

On 4 Oct, 23:08, Tim Watts wrote:
On 04/10/10 22:26, Andrew Gabriel wrote:

In ,
* *writes:
door.


Opening up the cavity is no big deal.


I will need to hold back the existing cavity wall insulation whilst cutting
back. I believe that it will be a wool filled insulation.


That will probably just stay put.
Be thankful it's not tiny polystyrene balls...


Yes - I can personally confirm that wool (or blown fibre) does not tend
to fall out - much at least. It's worth having a bit of glass wool to
hand (old tank jacket is a good source if there's one down the tip) and
just stuff a bit back as you go. But mostly it is pretty stable.


Mineral wool cavity wall insulation (blown and bats) are treated with
a moisture repellent to prevent water tracking across the cavity. Get
proper cavity wall bats from your local builder's merchant.
The benifit of opening the cavity is it removes a thermal bridge to
the cavity that would otherwise be left. There is no other advantage.
There is a vertical damp proof course in the brickwork.
Modern houses tend not to have a brickwork return in window and door
openings. They have a cavity closer that is usually plastic with a bit
of insulation attached. These are cheaper to install and remove the
thermal bridge. There is no point in removing this. If you feel the
need to attach your new brick/blockwork to the old you can buy screw-
in "wall starters".