(N. Thornton) wrote in message . com...
"Toby" wrote in message ...
N. Thornton wrote:
1:1:6 is very common, but has been widely criticised by the experts,
since the lime content causes thr cement to not checmically set
properly, and the cement clogs the pores preventing the lime going off
properly as well. The result is regular failures. But its still
commonly used. I expect it'll take another 10 years for the knowledge
to permeate.

So what would you suggest, or an expert recommend?

I'm no expert on this, I've just read a few papers on it, so I'd stick
my head in the sand and suggest asking an expert Seriously, when I
read it I was boggled with the complexity of what I thought was such a
simple thing.

I did discover one thing though, which is inclusion of 1% plastic
fibres increases longeveity by controlling cracks and increasing
strength under tension. The Victorians knew this principle, and it was
standard practice to include horsehair in their mixes because it
extended mortar life significantly.

I wish I could give us all a better answer. I still dont know what to
repoint the house with.


Regards, NT

Wickes (in their Good Ideas Leaflet no. 12 at
http://www.wickes.co.uk/scat/goodideas )
advocate the addition of plasticiser to standard mortar to get the
benefit of lime mortar; ie making it not too rigid or hard. Anyone
had experience of this or care to comment?

David