Hi

Im just about to start bricking up a doorway which will be a support
for an RSJ after I knock some of the existing wall through to form an
arch. I have been told by the structural enginner that I need to fully
bond the new brickwork with the old by toothing it in. Can anybody
give me some advice on how I go about doing this, do I remove every
second course and lay the new brick into the gap?

Also whats the best way to make sure I get a straight line, should I
use a plumb line or not bother due to the gap being so small?

Also what tool should I use to cut the bricks, I was planning on
hiring an electric cutter of some kind.

Thanks!

Richard

"Richard" wrote in message
om...
Hi

Im just about to start bricking up a doorway which will be a support
for an RSJ after I knock some of the existing wall through to form an
arch. I have been told by the structural enginner that I need to fully
bond the new brickwork with the old by toothing it in. Can anybody
give me some advice on how I go about doing this, do I remove every
second course and lay the new brick into the gap?

Also whats the best way to make sure I get a straight line, should I
use a plumb line or not bother due to the gap being so small?

Also what tool should I use to cut the bricks, I was planning on
hiring an electric cutter of some kind.

Thanks!

Richard

Just remove the half bricks at the end of every other course, so that you
can maintain the bond using full bricks.

Depending on the integrity of the wall, you may just be able to take them
out with a bolster, but using a grinder will give a neater finish (but will
produce more dust than you imagined possible!)

If you're doing anything more than light DIY it's almost always worth buying
a cheapish grinder instead of hiring one IMHO.

Alex

"Alex" wrote in message
...
"Richard" wrote in message
om...
Hi

Im just about to start bricking up a doorway which will be a support
for an RSJ after I knock some of the existing wall through to form an
arch. I have been told by the structural enginner that I need to fully
bond the new brickwork with the old by toothing it in. Can anybody
give me some advice on how I go about doing this, do I remove every
second course and lay the new brick into the gap?

Also whats the best way to make sure I get a straight line, should I
use a plumb line or not bother due to the gap being so small?

Also what tool should I use to cut the bricks, I was planning on
hiring an electric cutter of some kind.

Thanks!

Richard

Just remove the half bricks at the end of every other course, so that you
can maintain the bond using full bricks.

Depending on the integrity of the wall, you may just be able to take them
out with a bolster, but using a grinder will give a neater finish (but
will produce more dust than you imagined possible!)

If you're doing anything more than light DIY it's almost always worth
buying a cheapish grinder instead of hiring one IMHO.

Alex
Check with your engineer or BCO

All the houses round here with extensions that are toothed in seem to be
three courses chopped out then leave three etc etc With full new bricks top
and bottom of the tree courses Not as nice looking as every other brick but
guess there must have been a reason for this
Or there are metal channels you can bolt to the wall firfix etc

For removing the bricks you can drill out most of the mortar first then
clean out with a plugging or bolster chisel, an SDS drill is great for this
esp. if you have lime mortar

Steve

Richard wrote:
Im just about to start bricking up a doorway which will be a
support for an RSJ after I knock some of the existing wall
through to form an arch. I have been told by the structural
enginner that I need to fully bond the new brickwork with
the old by toothing it in. Can anybody give me some advice
on how I go about doing this, do I remove every second course
and lay the new brick into the gap?

Depends on his recommendation, I should ask. For maximum strength
alternate courses is best, but you can go every three or four.


Also whats the best way to make sure I get a straight line,
should I use a plumb line or not bother due to the gap being
so small?

A piece of batten would probably be fine.


Also what tool should I use to cut the bricks, I was planning on
hiring an electric cutter of some kind.

What are you cutting? To cut bricks, you can generally use
the edge of your trowel, or tap around them with a bolster
chisel for accuracy. If you mean to cut out the existing,
stitch drilling and/or a masonry saw would be OK and not
too dusty. A masonry saw is like an ordinary saw for timber
but with big TC teeth.


J.B.

Steve wrote:

Or there are metal channels you can bolt to the wall firfix etc

I don't believe these give the same strength of bond as toothing in.

--
Grunff

"Grunff" wrote in message


Steve wrote:

Or there are metal channels you can bolt to the wall firfix etc

I don't believe these give the same strength of bond as toothing in.

The three courses are the same height as a concrete block.

Use a boulster on that sort of toothing, a masonry drill and cold chisel
for every other course. I can't remember seeing an example of the latter
not intended to match face brick.


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

"Richard" wrote in message
om...
Hi

Im just about to start bricking up a doorway which will be a support
for an RSJ after I knock some of the existing wall through to form an
arch. I have been told by the structural enginner that I need to fully
bond the new brickwork with the old by toothing it in. Can anybody
give me some advice on how I go about doing this, do I remove every
second course and lay the new brick into the gap?

Also whats the best way to make sure I get a straight line, should I
use a plumb line or not bother due to the gap being so small?

Also what tool should I use to cut the bricks, I was planning on
hiring an electric cutter of some kind.

Thanks!

Richard

Why can't you use a mechanical fixing i.e. screwed on ties, wall starter, or
helical rods? These would hold the new work just as well.

The problem with toothing is that you can crack the toothed bricks very
easily when cutting the alternate courses. These cracks may be not be
visible on the surface but will crack further later. Also it can be very
hard to ensure the joints are full when you bond the new work, and so the
toothed brick remains unsupported. These can defeat the intended load
spreading of the bond.

Toothing tends to be frowned upon as a reliable bonding method - unless the
work is monitored and properly done.

However, if the work needs to be bonded as it will be seen, then cut out
with a disk cutter and avoid hammering, then make sure the joints are full
or pack with slate.

You don't follow a plumbline, but follow the bond of the existing wall. This
may mean spacing or cutting the new bricks to fit. If you mean horizontal
line, then you use a string line stretched across the opening for each
course.

dg