Roger Hayter posted
Max Demian wrote:

On 28/11/2017 20:45, Jim GM4DHJ ... wrote:
Having seen loads of imperial brick buildings fall down that were
built 1890
to about 1910 way does everybody go on about how wonderful lime mortar is
......?

The Ca(OH)2 turns into CaCO3 eventually by absorbing CO2 from the
atmosphere, which is a lot stronger.

Hydraulic lime is much stronger to start with, as it has silicates and
such-like in it, and sets somewhat like Portland cement. I have noticed
that the advice from the experts has changed radically several times in
the last fifteen years, so I suspect that there is a lot we really don't
know about using lime.

What we and our neighbours have noticed is that different experts give
different advice on solving the same problem. That too has been going on
for years.

--
Jack