Month: August 2017

Gypsum Is Not Talc

I’ve mentioned gypsum block before: it was the masonry-style predecessor to gypsum board, a manufactured pre-fab substitute for rough-coat plaster and lath. The picture above (click to enlarge it) is from an early 1960s building. That’s a standard gyp-block partition in a mechanical room, serving as a fire-rated divider between two spaces. “Gold Bond” was …

Gypsum Is Not Talc Read More »

Classic Damage Nicely Illustrated

It’s easy to come to the wrong conclusion here: it certainly looks like the mortar in the joints between the stone is being squeezed out, so that it projects from the stone face. Mortar of any kind doesn’t act like that – it’s not putty – but this is hard mortar with portland cement binder …

Classic Damage Nicely Illustrated Read More »

Scroll to Top