Stucco Painting in Toronto & the GTA

Should you paint stucco or leave it unpainted?

Leave it if the colour is still even and you like it after a wash. Paint it if you want a new colour, or if repairs and stains have left the wall patchy.

Unpainted cement stucco has three routes:

• Wash only. The finish stays as it is, which works while its colour is still even.
• Fog coat. Stucco trades spray on a thin, pigmented cement coat to renew faded colour. The wall keeps its cement finish, in a narrower colour range than paint offers.
• Paint. A full range of colours, and a film that sheds rain while letting water vapour out. The catch is that painted stucco needs repainting from then on.

Paint also changes the look a little. An industry bulletin notes that paint's thickness affects fine stucco textures, and its colour may not match unpainted panels. So paint whole walls or panels rather than patches. Our post on painting stucco covers synthetic stucco (EIFS), which follows its maker's own recoating rules.

Which stucco cracks can paint cover, and which need repair first?

Hairline cracks can usually be painted over; wider, growing or leaking cracks need a repair first. Cement stucco cracks a little as it shrinks and the house moves, and industry guides treat fine cracks as cosmetic. They are most common at the corners of windows and doors.

Crack	What it usually means	Before painting
Up to about 0.8 mm (1/32 inch), a credit card's thickness	Shrinkage or normal movement, and cosmetic	Paint brushed into the cracks hides them; patching isn't advised
About 0.8 to 1.6 mm (1/16 inch)	Wider than hairline, and worth sealing	Filled with sealant and an elastomeric patch, on one paint maker's sheet
Wider than about 1.6 mm	May let water reach the back of the stucco	Cut out and repaired before any coating goes on
Many new cracks, or cracks that return after patching	Possible movement in the wall or the house	A stucco contractor's opinion, or a structural engineer's

Industry guides advise against patching true hairline cracks, since a patch shows more than the crack. Hollow or bulging patches are a separate problem: they sound hollow when tapped, and loose stucco has to be repaired before paint. Any crack that lets water in comes first, whatever its width.

Is elastomeric coating better than regular paint on stucco?

Not always: elastomeric suits stucco with many fine cracks, but only at its full thickness, and it asks more of the weather. A 100% acrylic exterior paint suits most stucco repaints.

High-build coating:

a coating made to go on several times thicker than paint in each coat; elastomerics are the stretchy kind.

Here is how the two compare on one major paint maker's data sheets:

	100% acrylic exterior paint	Elastomeric masonry coating
Wet film per coat	About 0.13 to 0.15 mm	About 0.4 to 0.5 mm
Area covered per litre	About 7 to 10 m²	About 2 to 2.5 m²
Cracks it is rated to bridge	Not rated for it	Up to about 0.8 mm
Lowest air and wall temperature	1.7°C	10°C
Water vapour permeance	31 perms	32 perms

The elastomeric goes on about three times as thick, so a litre covers roughly a quarter of the area. It also asks for no rain for 24 hours after it goes on. Breathability depends on the product, not the category: these two sheets list almost the same permeance. Check the figure on the data sheet for the coating named in your quote.

Why can't stucco painting be priced from photos alone?

Because the details that move a stucco price are hard to judge in a photo. Crack widths, hollow patches, the surface under the old paint and the texture all need a close look.

• Cracks. A photo rarely shows whether a crack is 0.5 mm or 2 mm wide, and the repair differs.
• Hollow patches. They are found by tapping the wall, not by looking at it.
• The surface. Bare cement stucco, chalky old paint and EIFS each call for a different primer or coating.
• Texture. Rough stucco takes more paint than smooth, and an elastomeric system takes far more again.

That is why stucco usually needs a crew lead to see the walls before your written quote. Photos of each wall, with close-ups of any cracks, still come first: they show what to look at.