Masonry primer

Definition

An alkali-resistant primer made for portland-cement stucco, concrete block and concrete. It seals the porous surface and tolerates the high pH of fresh cement.

Why It Matters

Fresh stucco and fresh patches run around pH 12.5 to 13. Anything above about 9 is too alkaline for a finish coat to hold, so new stucco and patches need about 28 days to cure and a masonry primer before paint. Skipping it is why patches discolour or let go within a season.

Simple Example

A stucco crack repair on a Damonte Ranch house is left to cure for four weeks, primed with a masonry primer, then painted to match.

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