--- Ralph Walter <[log in to unmask]> wrote:
> I am surprised by your proposed use of, or
> consideration for use of, sealant
> in stone joints.

> The Great Man is of the opinion, which of course is
> also mine, that the
> sealant will trap any water which gets in, and will
> force the water to leach
> out or otherwise attempt to exit through the stone,
> and fuck up (as we say,
> technically speaking) the stone rather than just
> dribbling out from a mortar
> joint that could be much more easily repaired.

Hear this.  Agreed. One hundred percent. Provided we
are not talking about thin stone veneer (as I
understand that Philip Johnson's AT&T building was) -
see my previous post.

Now, if we are talking traditional stone masonry walls
- oh yeah - keep that sealant away, baby.

EXCEPT ...

For the horizontal joints between coping stones,
cornice units or projecting string courses where there
are no lead weatherings or other flashings present.
In situations like this, mortar will crack and allow
water into the stone much more quickly than sealant.
For my money, I'll specify a sealant joint on the top
surface and around the leading edge, then as soon as I
get past the drip, the transition to mortar will
occur.

And Ralph, just because we're down under, it doesn't
mean that the water drains upwards!

Cheers

david

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