Patching Brownstone
by Lynette Strangstad
Brownstone is a red- to darkchocolate-
brown sandstone that was
widely used as a building material in
the 19th century. It is also a "soft"
sedimentary rock, usually with a
noticeable mica content.
Brownstone is susceptible to water
damage that is often seen as too
complicated and costly to repair once
it begins. But don't despair. Although
it does take time, there are practical
and effective techniques to restore a
brownstone facade.
The Problem
The most common cause of
damage and deterioration is the
presence of water during freeze-thaw
cycles. Crumbling pointing, open
joints, and cracks from settling all
contribute to the problem. Water
enters between stones, becomes
trapped, and freezes and expands-
further damaging the joints and
Along with