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
