Finishes, Explained, Part 3: Venetian Plaster and Specialty Finishes

Stand close to a Venetian plaster wall and you can see into it. The coats show through each other, and the last one has been polished by the trowel, which gives the wall a depth flat paint doesn’t have. It is slow, hand-made work. It usually costs more than paint, and it needs care around water.

What goes into the air while it dries? California caps the VOCs (the compounds a coating gives off as it dries) for each type of coating, and decorative finishes get a higher cap than wall paint. A cap is a ceiling, though. It says nothing about what a given product contains.

Flat wall paint is held to 50 grams per liter, and faux finishing coatings, the decorative category, to 350. The lime plaster data sheet cited below lists its own VOC content at less than 1 gram per liter.

What it is

Traditional Venetian plaster is aged lime and fine marble powder, tinted and trowelled on by hand in thin coats. The last coat is worked until the blade polishes it, and the layers showing through each other give the depth.

Is it the same as limewash? No. Both can be lime-based, but limewash is a thin brushed coat with a matte, chalky look. Venetian plaster is built up in trowelled coats and polished. Products differ by maker, so we follow each maker’s data sheet for primer, coats and drying times.

How it goes on, and how long it takes

Expect three coats, each thinner than the last. These figures are from one maker’s lime plaster.

The first coat evens out the wall, and it must not be shiny or the next coats won’t hold. The third goes on while the second is still damp and is trowelled to a polish. Together they come to about 0.8 to 1.2 millimeters. The same sheet gives 3 hours to dry to the touch and 48 hours below the surface.

Can it go over a painted wall? Often, yes. The data sheet we cite calls for a painted wall to be brushed down and given a coat of the maker’s primer first, and we check the wall during the assessment. The rest of our steps are the same as for any coating system.

1. We check the surfaces and specify the coating system for each one.
2. The wall gets a Level 5 skim coat, sanded flat.
3. Where the system calls for it, a primer goes on for adhesion and even absorption.
4. Then the plaster goes on by hand with a steel trowel, to the maker’s instructions.

Which rooms it suits

It suits walls you see up close and in raking light, in living rooms, entries, dining rooms and powder rooms. On bathroom walls, in kitchens and on splashbacks, the data sheet we cite calls for a final coat of wax or soap. Keep it out of showers, where water runs down the wall.

Other specialty finishes

Our other fine finish work is for wood. That means sprayed lacquer and conversion varnish on cabinets and millwork, and Fine Paints of Europe Hollandlac for a mirror-like gloss on doors and trim, as Part 2 covers. If you have another finish in mind, ask us. We’ll tell you plainly whether it’s work we do.

Is Venetian plaster right for your wall?

Samples on site are the best way to judge it. Lime plaster changes through the day as the light moves, and it suits old houses and plain modern rooms alike. Its look also varies with the hand that trowels it, and it needs care around water and stains.

That’s the last part of the series. Part 1 covers color drenching and sheen, and our interior painting page covers the rest of the work. When you’re ready, request an estimate or call us at (650) 961-7415.