Crumbly, soft bricks and leaky walls *PIC*

[Anonymous]

Here's a shot of the gable end following removal of much of the cement pointing from the area of oldest bricks. I had managed to re-point and repair about a quarter of the area by the end of today.

As you can see, behind the cement there were some large cracks and some very loose bricks (which are now holes).

Quite a bit more work to be done but it will have to wait until the weekend now.

 

[Anonymous]

This is very interesting brickwork though! I presume the cracks are old and the wall is stable now?

 

[Anonymous]

No not advertising blurb just hopefully helpful information, which is no different to what the spab themselves say copied below

"Q. Which lime should I use?
A. The SPAB generally advocates the use of repair materials that match those used originally. Our forefathers appreciated that the more hydraulic a lime the greater its strength, but the lower its permeability and flexibility; so, the right balance needed to be struck for the particular job in hand. The slow set and workability of non- hydraulic lime, for example, is ideal for internal plasterwork. Where, however, extra durability in early life is required, say with a moderately exposed external wall, a weak hydraulic lime (or, if unavailable, a non-hydraulic one with a pozzolanic additive such as tile dust) might be appropriate for pointing or rendering.
Whereas lime putty was employed historically for plastering inside, mortar for masonry seems to have been produced more cheaply by dry-slaking. Some companies produce dry-slaked mixes."

Chemical analysis of old mortars in our area back this up with the vast majority being feebly hydraulic with some of moderate strength even some plasters were hydraulic.

 

[Anonymous]

It's a very complex subject, with a great deal of difference of opinion.

I'm off to catch a train, so can't discuss!

 

[Anonymous]

Out of interest... Do SPAB buy advertising on this site?

Please dont take that the wrong way Evelyn - Im not about to rant against you or SPAB.

 

[Anonymous]

*** This is very interesting brickwork though! I presume the cracks are old and the wall is stable now? ***

I think the cracks are very long standing and there's no ongoing movement. They had previously been filled/rendered over with cement. Lining most of the inside of the wall is an inner wall of concrete blocks that was built when the staircase was moved about 15 years ago. This means that the holes do not go right through to the inside and there is some additonal structural strength there.

I'm intending to stitch the cracks back together as I go. So far I've only had a relatively narrrow crack to repair and that one has come out OK. The wider ones will be more of a challenge but the end result has to be better than what was there before.

As you can see from the pictures, these bricks are part of the original terrace and the wall was once an internal one. At some point, the roof height was dropped and the rebuilt section formed a much lower and very tiny cottage with just one bedroom built right up into the roof space.

 

[Anonymous]

Simon and Rob provide free links to certain conservation organisations. These are of course registered charities, not businesses.

I think it is possibly time tribute was paid to them for this very generous gesture!