I like the new listserv motto...a propos!  So, regarding the painting of concrete, here are some thoughts on this fine Sunday morning.  

The Nashville Parthenon, rebuilt in 1926, is and was unpainted, except for the colorful plaster soffits.  John J. Earley designed the concrete mix with specifically colored aggregates to provide the color we see and never relied on coatings or additives.  Fortunately it has never been painted, so restoration didn't have to deal with paint removal.

Isn't it nice to have a material that doesn't require paint coatings for finishing?  Isn't better to let the material breath?  Aren't we glad that concrete doesn't rely on paint coatings so we have a cheap alternative?  

Even stucco doesn't require paint, such as all those early 20th century stuccoed foundations and Craftsman bungalows, and especially all those pre-Civil War Greek Revival buildings.  I live in one of the latter, and I know that removal of the paint is impossible without damaging the stucco, but yet the paint coatings have built up so much that the peeling paint pulls stucco with it.  Dilemma for me, if we decide to tackle repainting - or paint removal and then what- to restore the facade.

Paint is cosmetic, covers up stains, makes the surface look homogeneous, but it doesn't make it perform better.  Eventually it peels, or develops a build-up from successive coatings, and sandblasting has been used often to remove paint from concrete.  Coatings may then be needed to provide a seal or water repellent to protect embedded rebar.  

Fallingwater, built in 1936-39, has always been painted, although initially with a cementitious paint that was compatible with the concrete.  Paint has been completely removed twice and is now painted again to match the original color, but not with cementitious paint.  I've forgotten now what the current paint is, but someone will chime in with the data, I'm sure.

Ilene R. Tyler, FAIA
QUINN EVANS | ARCHITECTS
219 1/2 N. Main Street
Ann Arbor, MI  48104
ph: 734 663-5888
fx: 734 663-5044



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