Dunn-Edwards EFF-STOP® Premium
Interior/exterior masonry primer-sealer
Product code ESPR00
Dunn-Edwards calls for at least 14 days of cure before priming new masonry. I wait 30. Painting stucco before it has cured leaves the pH too high, and that causes burnout on the underside of the paint film.
The data sheet calls for at least 14 days of cure on new masonry. I wait 30 days minimum, unless the wall has been primed with Eff-Stop, which shortens the time before you can paint.
If new stucco is painted before it has time to properly cure, the pH of the stucco is too high and it will cause burnout on the underside of the paint. Allowing stucco to cure naturally lowers the pH. Nothing about the paint changes while you wait—the wall does.
Efflorescence is the thing homeowners notice without knowing the word for it. What it looks like depends on how severe it is. It can look like faded paint, where the color is discolored. Or it can look like a white powdery substance on the surface of the paint that can be removed with a dry brush. If either of those is on your wall, that is what you are looking at.
On coverage, the sheet says 225 to 275 square feet per gallon. On rough new stucco it is probably 150 to 175. Fresh stucco is porous and it takes what it takes.
When a house is not ready, I explain the dangers of painting too soon and the benefits of letting the stucco cure properly first. That conversation is not always the one a builder or a homeowner wants to have on a schedule.
| Coverage | 225–275 sq. ft. per gallon (150–175 on rough new stucco, in our experience) |
|---|---|
| VOC | 20 g/L as supplied (5 g/L maximum reactivity-adjusted) |
| Dry to touch | 30–60 minutes |
| Recoat | 2–4 hours |
| Film build | 5.5 mils wet / 2.0 mils dry |
| Application | Brush, roller, or airless |
| Temperature | Do not apply below 50°F |
| Masonry pH | Rated for surfaces up to pH 13 |
| New masonry | Data sheet: at least 14 days cure. We wait 30. |
| Substrates | Plaster, brick, stucco, tilt-up concrete, poured-in-place concrete, concrete block, smooth trowel finishes |
Manufacturer figures from the Dunn-Edwards product data sheet. Coverage figures marked “in our experience” are ours, measured on our own jobs in the Phoenix valley. Sources: https://www.dunnedwards.com/product/eff-stop-premium/ and https://www.dunnedwards.com/wp-content/uploads/2015/01/EN-ESPR00-PDS.pdf. Dunn-Edwards® and EFF-STOP® are trademarks of Dunn-Edwards Corporation. We are not affiliated with or sponsored by Dunn-Edwards; we buy this product at retail like anyone else.