On 17 Aug, 09:25, PeterC wrote:
Last Autumn there was a mention in a thread about 1950's brickwork being
porous.
About that time I had to drill a couple of holes in the gable wall - it
faces SW - and the debris was like a crumbly paste rather than dust for
about 15 - 20mm in.
The bricks are heavily patterned - a vertical herringbone groove - which I
think are Rustic(?) from c. 1950.

Is it worth treating the wall and, if so, what sort of gunk to put on it?

There are 2 possibilities on this page

http://www.everbuild.co.uk/products/...s/26,Surface-T...

although the solvent-based one looks a bit nasty!

Any suggestions please?
--
Peter.
The gods will stay away
whilst religions hold sway

Dear Peter
Brick is supposed to be porous. If it is not causing any problem do
not treat it. If, however, it is accumulating water to the extent
that you are getting frost damage or loosing heat badly then I see no
reason why you cannot treat the brick. All treatment ideally should
be reversible in accordance with good SPAB practice and the idea of
putting on a layer of silicone is not a good one. If , however, you
can infuse the silane based products mentioned but others in this
thread it is naturally removed over a period of decades and as far as
we know can do no harm. BRE did work with silanes some 30 plus years
ago on statues that were degrading (I think limestone but cant
remember)
I know the firm Safeguard, having bought from them for 35 years or
more and they are reputable and have their own research PhD a chap
called Eric ? with whom I have spoken in the past and you could do far
worse than them
http://www.safeguardeurope.com/appli...enetration.php
If you are interested

Chris