John -

I will check the mortar - there is one interior spot upstairs that has both
new and old section exposure inside the house.  As I mentioned earlier, I
believe the age difference between the two sections to be small.  I don't
recall seeing anything in the abstract to lead me to believe otherwise.

And Ohio isn't that far away, considering where some of these other folks
live!

- Pam

-----Original Message-----
From: john burnell [mailto:[log in to unmask]]
Sent: Wednesday, January 01, 2003 9:07 PM
To: [log in to unmask]
Subject: Stone House BP List



    Hello -- from my far away distance in cyberspace, I may be able to offer
some small guidance to your house issue.

    It is obviously difficult to know exactly what is happening here, but
here are a few things:

    Examine the mortar around the cracks.

    Find a spot in the wall -- wherever -- that you suspect is the original
mortar.  It will be soft -- you can scratch it with your fingernail.  If the
mortar where the cracks are occuring is this softish mortar, then your
problem might be structural.  Lime mortar, which surely your house was built
with (almost every masonry building pre-1880s or so is lime mortared) tends
to have some flex, and can move and actually re-seal itself so long as the
movement is gradual enough.

    Again, if the mortar around the cracks is scratchable, then your problem
is likely structural.


    The other thing to look for is cement-based (or Portland) mortar around
the cracks.  This will mean that it has been repointed sometime this past
century by a mason who knew no better.  Portland has little to no flex and
will crack at the slightest movement -- and a traditional masonry structure
such as yours is built to handle movement.  If the mortar around the cracks
is Portland -- which you cannot scratch (it is also often a grayish color as
well) then you simply may have a repointing problem.


    This is the first thing I might look at -- the mortar joints, and then
go from there.
    I'm not entirely clear as to the age of the "new" section of your house
-- again, that can also tell you also what type of mortar and what type of
structure is likely.
    Feel free to keep in touch if you need further feedback.


Best wishes,

John Burnell

Kent, Ohio

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