Dear all, I have just demolished a section of garden wall at my property
that was being pushed over by some self seeded trees that should have
been removed years ago before they bacame a problem. The demolished
section was about 15ft long and is around 6ft6in high at one end,
reducing in a graduated fashion to around 3ft at the other (on account
of the slope of the land).

I arranged for quotes to re-build from a few bricklayers, but was a bit
shocked at the prices; all are around £1200-£1300. Is this way over the
top? When I have watched briccies working on a major construction, it
seems that they can throw up a wall in no time at all, but most of the
chaps who have visited me are saying its a 3-4 day job!

I am now considering DIY, but to make the job as easy and quick as
possible, I think I will use large conrete blocks rather than bricks and
then render the wall afterwards (part of the existing brick wall is
rendered anyway). I want the wall to be the thickness of two courses,
but rather than actually building two separate courses, could I just use
the blocks on their sides? I wonder whether there are any strength
implications to this, since the blocks are far easier to break with a
force from above when laid on their sides than when in their normal
orientation. Would I be running a much greater risk of cracks caused by
settlement if I use the blocks on their sides?


Thanks, Jim

Jim Walsh wrote:
Dear all, I have just demolished a section of garden wall at my property
that was being pushed over by some self seeded trees that should have
been removed years ago before they bacame a problem. The demolished
section was about 15ft long and is around 6ft6in high at one end,
reducing in a graduated fashion to around 3ft at the other (on account
of the slope of the land).

I arranged for quotes to re-build from a few bricklayers, but was a bit
shocked at the prices; all are around £1200-£1300. Is this way over the
top? When I have watched briccies working on a major construction, it
seems that they can throw up a wall in no time at all, but most of the
chaps who have visited me are saying its a 3-4 day job!

I am now considering DIY, but to make the job as easy and quick as
possible, I think I will use large conrete blocks rather than bricks and
then render the wall afterwards (part of the existing brick wall is
rendered anyway). I want the wall to be the thickness of two courses,
but rather than actually building two separate courses, could I just use
the blocks on their sides? I wonder whether there are any strength
implications to this, since the blocks are far easier to break with a
force from above when laid on their sides than when in their normal
orientation. Would I be running a much greater risk of cracks caused by
settlement if I use the blocks on their sides?




As it's so high I guess you'd need proper strength calculations for
both the wall and the foundations. and/or go way over the top with the
strength.

I want the wall to be the thickness of two courses, but rather than
actually building two separate courses, could I just use the blocks
on their sides?

It would be much easier and less labour intensive just to buy blocks of
sufficient width. Although 440x215x100 is the common block size, you should
be able to find 440x215x215 in stock at a builder's merchant and they will
order you some if they don't have any.

Don't forget to read up about how to design walls and their foundations. The
wall needs to be designed, not just thrown up. You also need to decide on
whether you want aerated or dense concrete. Personally, I would just use
aerated, especially as it will be rendered, so appearance is less important.
The only advantage of dense blocks is really just resistance to surface
damage and better appearance. In terms of structural strength, they're just
fine. They are also slightly less likely to kill you if the wall falls down.

Many of these blocks, such as the Celcon Standard 440x215x215 I would use
for this application, can not only be used externally, but are also suitable
for use in foundations, too.

Christian.

Jim Walsh wrote:
Dear all, I have just demolished a section of garden wall at my
property that was being pushed over by some self seeded trees that
should have been removed years ago before they bacame a problem. The
demolished section was about 15ft long and is around 6ft6in high at
one end, reducing in a graduated fashion to around 3ft at the other
(on account of the slope of the land).


Tell planning about it if it's that high or you could end up having it
removed, a garden wall fell down a few weeks ago and killed a child and many
arses have been kicked and ******** removed as a consequence.


I arranged for quotes to re-build from a few bricklayers, but was a
bit shocked at the prices; all are around £1200-£1300. Is this way
over the top? When I have watched briccies working on a major
construction, it seems that they can throw up a wall in no time at
all, but most of the chaps who have visited me are saying its a 3-4
day job!

It *is* a 3-4 day job.

I am now considering DIY, but to make the job as easy and quick as
possible, I think I will use large conrete blocks rather than bricks
and then render the wall afterwards (part of the existing brick wall
is rendered anyway). I want the wall to be the thickness of two
courses, but rather than actually building two separate courses,
could I just use the blocks on their sides? I wonder whether there
are any strength implications to this, since the blocks are far
easier to break with a force from above when laid on their sides than
when in their normal orientation. Would I be running a much greater
risk of cracks caused by settlement if I use the blocks on their
sides?

Or you could just use the trench blocks which are 2 feet long, ten inches
wide and nine inches deep, they're similar to thermalite and are easily cut,
carried and laid, they cost more than normal blocks but the wall is
completed in half the time.

"Jim Walsh" wrote in message
...
Dear all, I have just demolished a section of garden wall at my property
that was being pushed over by some self seeded trees that should have been
removed years ago before they bacame a problem. The demolished section was
about 15ft long and is around 6ft6in high at one end, reducing in a
graduated fashion to around 3ft at the other (on account of the slope of
the land).

I arranged for quotes to re-build from a few bricklayers, but was a bit
shocked at the prices; all are around £1200-£1300. Is this way over the
top? When I have watched briccies working on a major construction, it
seems that they can throw up a wall in no time at all, but most of the
chaps who have visited me are saying its a 3-4 day job!

I am now considering DIY, but to make the job as easy and quick as
possible, I think I will use large conrete blocks rather than bricks and
then render the wall afterwards (part of the existing brick wall is
rendered anyway). I want the wall to be the thickness of two courses, but
rather than actually building two separate courses, could I just use the
blocks on their sides? I wonder whether there are any strength
implications to this, since the blocks are far easier to break with a
force from above when laid on their sides than when in their normal
orientation. Would I be running a much greater risk of cracks caused by
settlement if I use the blocks on their sides?


Thanks, Jim

The BRE Good Building Guide (GBG 14) recommends that for walls of this
height in sheltered locations they should be 300mm in height. Once you get
to this thickness the orientation of the block makes little difference. It
also recommends for stability reasons that the minimum density of block
should be 1500kg/m3. In any case I wouldn't recommend rendering lightweight
block as I have seen the face of the block shear off leaving you with a
really awful looking wall. The foundation should be 550mm wide unless you
live in the north of Scotland and 275mm deep. If you do not live in a
sheltered urban area then a simple wall will not have sufficient strength.
This assumes that you have good firm soil to build off.

In answer to your question though. A 200 mm wide wall form from block on
side is 3 times stronger than a 100m thk wall. A wall formed from 2 leaves
of 100 block with no ties between the leaves is twice as stronger as 100mm.
A wall collar jointed 200mm thk wall (blocks tied at each coarse) is just
less than 4 times as strong as a 100 mm wall.

Darryl