Hi,

I'm planning to do a bit of exterior redecoration. We have a bay window which is a triumph of the victorian cowboys who built this place. Its foundations are (I think) two courses of bricks sitting on nice London clay. Consequently it's not very stable. The last time it cracked up it was shored up using helical bars. They're better than nothing, but there is still some movement, and things have cracked up a bit since the last repaint (about six years ago).

Anyway, as the options seem to be either underpinning it, or just filling the cracks every few years, I'm opting for the second. So the question is what's the best thing/technique to use to fill it. Here are two photos:
http://imageshack.us/g/254/imag0181g.jpg/
One shows the cracked rendered plinth. The other one shows a crack in the sill - it sounds pretty hollow underneath and I suspect when I give it a whack a large chunk of it will fall away leaving a big hole.

Cheers!

Martin

In message ,
Martin Pentreath writes
Hi,

I'm planning to do a bit of exterior redecoration. We have a bay window
which is a triumph of the victorian cowboys who built this place. Its
foundations are (I think) two courses of bricks sitting on nice London
clay. Consequently it's not very stable. The last time it cracked up it
was shored up using helical bars. They're better than nothing, but
there is still some movement, and things have cracked up a bit since
the last repaint (about six years ago).

Anyway, as the options seem to be either underpinning it, or just
filling the cracks every few years, I'm opting for the second. So the
question is what's the best thing/technique to use to fill it. Here are
two photos:
http://imageshack.us/g/254/imag0181g.jpg/
One shows the cracked rendered plinth. The other one shows a crack in
the sill - it sounds pretty hollow underneath and I suspect when I
give it a whack a large chunk of it will fall away leaving a big hole.

How old is the house? If it's been there a long time, and there's no
sign that anything will collapse, I would be tempted to repair things
with something flexible, so at least the cracks won't reappear (or at
least so they will only appear at the junction of the flexible and
non-flexible parts - so you will know where they are).
--
Ian

On Wednesday, August 29, 2012 12:55:54 PM UTC+1, Ian Jackson wrote:

How old is the house? If it's been there a long time, and there's no

sign that anything will collapse, I would be tempted to repair things

with something flexible, so at least the cracks won't reappear (or at

least so they will only appear at the junction of the flexible and

non-flexible parts - so you will know where they are).

--

Ian

Hi Ian,

The house was built around 1880. But anyway, there aren't any structural problems with the rest of it - it's just the bay window that has no foundations. So really I'd already decided that it's just a filler job. I'm wondering what the best filler is to use for this, and particularly for the sill, which I think will be left with a gaping hole after I've removed the bit that's cracked away.

In message ,
Martin Pentreath writes
On Wednesday, August 29, 2012 12:55:54 PM UTC+1, Ian Jackson wrote:

How old is the house? If it's been there a long time, and there's no

sign that anything will collapse, I would be tempted to repair things

with something flexible, so at least the cracks won't reappear (or at

least so they will only appear at the junction of the flexible and

non-flexible parts - so you will know where they are).

--

Ian

Hi Ian,

The house was built around 1880. But anyway, there aren't any
structural problems with the rest of it - it's just the bay window that
has no foundations. So really I'd already decided that it's just a
filler job. I'm wondering what the best filler is to use for this, and
particularly for the sill, which I think will be left with a gaping
hole after I've removed the bit that's cracked away.

Having done, in the past, a fair number of body repairs on my
ever-rusting bangers, I'd be tempted to use up some of my car repair
materials (fibreglass matting, resin and paste). I suppose 'Plastic
Padding' is maybe the most appropriate (especially the flexible type).
However, there are probably better 'genuine' building materials for the
job - which others will advise on.
--
Ian

Ian Jackson wrote:
In message ,
Martin Pentreath writes
On Wednesday, August 29, 2012 12:55:54 PM UTC+1, Ian Jackson wrote:

How old is the house? If it's been there a long time, and there's no

sign that anything will collapse, I would be tempted to repair things

with something flexible, so at least the cracks won't reappear (or at

least so they will only appear at the junction of the flexible and

non-flexible parts - so you will know where they are).

--

Ian

Hi Ian,

The house was built around 1880. But anyway, there aren't any
structural problems with the rest of it - it's just the bay window
that has no foundations. So really I'd already decided that it's just
a filler job. I'm wondering what the best filler is to use for this,
and particularly for the sill, which I think will be left with a
gaping hole after I've removed the bit that's cracked away.

Having done, in the past, a fair number of body repairs on my
ever-rusting bangers, I'd be tempted to use up some of my car repair
materials (fibreglass matting, resin and paste). I suppose 'Plastic
Padding' is maybe the most appropriate (especially the flexible type).
However, there are probably better 'genuine' building materials for the
job - which others will advise on.

One thing I discovered about 'genuine building materials' is that they
have only one overriding advantage. They are cheap.

One would be far better off with - say - a house made of GRP lined with
PU foam, and self colored gel coat on the outside, than rendered.
Especially if it were epoxy and not polyester. Bolts would be better
than nails.


Beams of Titanium would be far better than wood. etc.

I leave you to draw the obvious conclusions.


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On 29/08/2012 17:14, Ian Jackson wrote:
In message ,
Martin Pentreath writes
On Wednesday, August 29, 2012 12:55:54 PM UTC+1, Ian Jackson wrote:

How old is the house? If it's been there a long time, and there's no

sign that anything will collapse, I would be tempted to repair things

with something flexible, so at least the cracks won't reappear (or at

least so they will only appear at the junction of the flexible and

non-flexible parts - so you will know where they are).

--

Ian

Hi Ian,

The house was built around 1880. But anyway, there aren't any
structural problems with the rest of it - it's just the bay window
that has no foundations. So really I'd already decided that it's just
a filler job. I'm wondering what the best filler is to use for this,
and particularly for the sill, which I think will be left with a
gaping hole after I've removed the bit that's cracked away.

Having done, in the past, a fair number of body repairs on my
ever-rusting bangers, I'd be tempted to use up some of my car repair
materials (fibreglass matting, resin and paste). I suppose 'Plastic
Padding' is maybe the most appropriate (especially the flexible type).
However, there are probably better 'genuine' building materials for the
job - which others will advise on.

Nothing better than car body filler IME, preferably a cheap 3.5 litre
job from a trade outlet. £15 ish IIRC