Venetian plaster is the term used to describe the decorative application of materials in the tradition of the Renaissance architecture of Venice, Italy. Builders in Venice needed a way to make buildings sturdy and visually appealing while still being lightweight enough to avoid sinking into the mud below the city. However, its origins are much older, dating to ancient Roman times. We can see evidence of it today in the villas of Pompeii and in various Roman structures.
Traditional Venetian plaster is a putty of marble flour and slaked lime. The lime and marble are ground to a very fine powder, allowing the plaster to be troweled on in thin layers, almost as thin as paint film.
Venetian plastering is a beautiful finish that can create a unique and beautiful surface ranging from glossy marble to warm and worn. It is now a much sought after finishing technique, particularly for high-end projects.
Care of Unsealed Venetian Plaster
If the plaster isn’t sealed, use a rag and warm water to clean. Gently rub out the dirt. If that doesn’t work, use a rag, water and a touch of soap, or fine grit sandpaper. Wet the area, and then use the sandpaper.
If an oily spot is stubborn to water and soap, use clear spirits, not oily spirits like Turpentine (test a small spot first.) If all else fails, add water to the same color plaster as used on the wall, making a slurry or paint out of it, then dab the troubled area with slurry.
Care of Sealed Venetian Plaster
There are several types of sealers: Natural sealers, acrylic sealers, various waxes and glazes. Sealers are obviously made for extra protection against dirt, mold, mildew, water and other undesirables. Each sealer has pluses and minuses.
If the plaster is sealed with a natural sealer like olive oil sealer, wax, saddle soap or other natural sealers, use that product to try to clean with. If that doesn’t work, try the same methods as listed above for unsealed plaster, and then be sure to reseal the plaster with the same product.
Natural sealers, such as Vasari Olive Oil Sealer, are most commonly used in general areas including the kitchen. It can take dirt, wine spills and oil spills. It’s easy to apply, odorless, it breathes, is easy to fix or reapply, can be colored for glazing and enhances the color and richness of the wall.
Olive oil sealer will also deepen the plaster color by as much as 50%, so you can use less pigment. It is easy to polish to a high sheen, feels very nice and is very easy to clean. It is removable with water, which is advantageous for patches or changing the wall color. Lastly, it is completely natural.
If cleaning acrylic sealed plaster, use the same methods (with the exception of cleaning it with acrylic sealer), then reseal the spot if it had to be sanded. Acrylic sealers, like Vasari Acrylic Sealer, are meant for very water prone areas, such as near sinks, baths, near showers, toilets, etc.
It is not recommended to put plaster directly in front of water, such as shower stalls. With direct and frequent water contact, the plaster would need to be reapplied every 5 years or so and if this is neglected, it could be trouble depending on the substrate.
Acrylic Sealer is essentially a coat of plastic. If the look is too synthetic, you can easily mask it by applying wax, such beeswax or carnauba wax. Two coats of Acrylic Sealer will make the plaster extremely durable to the elements.
Waxes are very beautiful and the traditional way to go. Real waxes like beeswax and carnauba can add protection and give the wall a marvelous luster that is difficult to duplicate. With proper care and maintenance your Venetian plaster will last for years. This time tested plaster technique will bring an air of ancient art to your décor.