When you are bricking up an external door are you supposed to "open up" and
expose the existing wall cavity or do you just brick up the gap (with it's
own cavity)?



--
Adam

ARWadsworth wrote:
When you are bricking up an external door are you supposed to "open up" and
expose the existing wall cavity or do you just brick up the gap (with it's
own cavity)?



You probably will find the cavity exists anyway on a modernish house
right up to the frame.

I would definitely open it up and remove alternate half bricks etc to
get a good continuos cavity and brick key. But then it would be my house.

Quick'n'dirty if I was a builder on a budget..

On 04/10/10 19:46, The Natural Philosopher wrote:
ARWadsworth wrote:
When you are bricking up an external door are you supposed to "open
up" and expose the existing wall cavity or do you just brick up the
gap (with it's own cavity)?



You probably will find the cavity exists anyway on a modernish house
right up to the frame.

I would definitely open it up and remove alternate half bricks etc to
get a good continuos cavity and brick key. But then it would be my house.


Yes - it's not hard.

Angle grinder (really! ;- ) to cut the mortar between the half bricks,
and remove. You can key both sides in an hour or less. Hammer and
bolster would work too but not quite as quick.

Pack mortar in tight with a bit of wood on these when building up the
wall and it will be a very strong joint.

I did the same to extend a wall by a foot (also a door opening that was
moved along a bit).

Quick'n'dirty if I was a builder on a budget..

They will be... Metal strip if you're lucky (though that is a fairly
strong solution) or a couple of nails banged in if they are really cheap
*******s.

On 04/10/10 20:58, Tim Watts wrote:
Pack mortar in tight with a bit of wood on these when building up the
wall and it will be a very strong joint.

I forgot to add - when I did my wall extension, I also inverted the new
bricks where they keyed in so I had a frog facing a frog - fully packed
with mortar.

That's probably over engineered for a full doorway bricking up but as I
was adding a little wibbly bit on the end of a wall, it was necessary to
make the joint really solid...

Tim Watts wrote:
On 04/10/10 19:46, The Natural Philosopher wrote:
ARWadsworth wrote:
When you are bricking up an external door are you supposed to "open
up" and expose the existing wall cavity or do you just brick up the
gap (with it's own cavity)?



You probably will find the cavity exists anyway on a modernish house
right up to the frame.

I would definitely open it up and remove alternate half bricks etc to
get a good continuos cavity and brick key. But then it would be my
house.

Yes - it's not hard.

Angle grinder (really! ;- ) to cut the mortar between the half
bricks, and remove. You can key both sides in an hour or less. Hammer
and bolster would work too but not quite as quick.


I guess that there is already some sort of vertical DPM in place around the
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.


They will be... Metal strip if you're lucky (though that is a fairly
strong solution) or a couple of nails banged in if they are really
cheap *******s.


It might be the metal strips for the external part of the wall. It is not
brick but concrete bricks. The idea is to brick up the old door and then
render the new brickwork to look like it was concrete bricks.

--
Adam

In article ,
"ARWadsworth" 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...

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

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.

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".

On 4 Oct, 19:42, "ARWadsworth" wrote:
When you are bricking up an external door are you supposed to "open up" and
expose the existing wall cavity or do you just brick up the gap (with it's
own cavity)?

--
Adam

Further to above, if your house is very old it may have no insulation
at all in the cavity. If it is very new it may have a "partial fill"
system, ie ridgid boards fastened to the inner leaf of brickwork by
clips on the wall ties. This is only likly on houses less then ten/
fifteen years old.
Things will start to become apparent when you remove the door frame.

On Oct 5, 10:30*am, harry wrote:
Further to above, if your house is very old it may have no insulation
at all in the cavity.
Cavity? What is this cavity of which you speak?

http://www.aecb.net/forum/index.php?topic=561.0 suggests cavity wall
construction moved east across the country between mid-19th and
mid-20th century. I'm from Cambridge, and would have guessed they
became common in the 50's.

Cavity wall insulation didn't become required until the 70's, which is
hardly "very old". In fact, it wouldn't surprise me if the majority
of our housing stock predates cavity wall insulation.