Simple And Effective

That’s the underside of the porch of a Brooklyn church. The brick wall is the wall of the main body of the building, the slab above is the floor of the porch between that wall and the street. A few things of note…

First, the brick below the porch slab shows signs of extended periods of wetness. My guess is that’s a combination of water running down the face of the building and water sitting on the slab drifting towards this edge. For a 130-year-old building and a cellar room that very likely has received zero maintenance ever, it doesn’t look so bad.

The slab above is what really caught my eye. It’s a single slab of sandstone – brownstone – that covers the entire porch area, or some 120 square feet. I don’t know exactly how thick it is, but if it’s as thin as 6 inches (it’s probably thicker) it weighs some 8,000 pounds. It has done its job just fine, even though we no longer use masonry as flexural structure in this manner. The peeling paint appears to be an old coat of whitewash. Since this area is protected from the weather and the stone is so thick that rainwater hasn’t been seeping though it, the whitewash would only get wet from condensation, which over the decades has been enough to remove most of it. The purpose of whitewashing the ceiling is simple: this room had one small window, barely above grade outside, and was built before electric light was available. A white ceiling helped illuminate it.

To recap: a stone slab and whitewash, instead of reinforced concrete and lights. It’s worked.