Grassello Venetian Plaster
Extremely shiny Marmorino Polished Plaster for mirror effects
Grassello Venetian Plaster is a Marmorino containing very small marble powders. This allows achieving extremely shiny finishes. Unlike other Venetian plasters, its surface has no matt / polished areas but is uniformly polished. Grassello Fine is the ideal material to create mirror Venetian plasters finishes.
Furthermore, because Grassello polished plaster has practically no pores, it is very easy to waterproof, making it ideal for bathroom walls.
Because it is applied in very thin coats, Grassello Plaster has a very small consumption per square meter, and greater yield than other Marmorino Polished Plasters.
Of all the Marmorino Polished plasters, this finish made of finely ground lime and marble powders gives the most shine. The movement between the darks and the lights is gradual and the surface reflects the light very well, almost as in a mirror. Unlike other Venetian plasters, its surface has no matt / polished areas but is uniformly shiny.
Grassello Plaster is a natural mineral wall covering for fine decorative finishes on interior walls. It is highly appreciated for its aesthetic effect, unique when properly lighted. It is used in sophisticated environments, such as reception areas, offices, villas. Because Grassello Fine is practically pores-free, it is very easy to waterproof, making it ideal for bathroom walls, as an alternative to marble and ceramic. The textured chiaroscuro effect may or may not be visible depending on the application technique.
Packaging of Grassello Venetian Plaster
Stucco Grassello Plaster comes in paste form in 24, 16, and 8 kg buckets.
The product is white and can be tinted with our Colour System.
Yield of Grassello Plaster
24kg of Stucco Grassello (1 bucket) = 28 square meters
Composition of Grassello Venetian Plaster
Very aged, finely filtered slaked lime putty, special powdered marble granules sifted and selected according to granule size, water, and special additives (no more than 1,8% total in wet volume).
Application of Stucco Grassello Plaster
Note: This is a description of the normal application.
Tools necessary for application: Normal big trowel, good big trowel, medium size good trowel, soft cloth.
Protection of the work area: Apply masking tape and protective material over the baseboards and around windows and doors.
Don’t apply in temperatures below 5°C (41°F).
- Remember to have a strong light parallel to the wall and situated on only one of the two sides of the wall you are working on (usually on the same side other sources of light come from such as the windows). In this way the shadow of the trowel allows you to see the actual state of the finish. Every so often, during the second and third coats, the light should be moved so that the wall doesn’t dry out too much in one spot from the heat of the lamp.
- The first coat of Grassello Venetian Plaster can be either white or colored. The first coat is applied with a metal trowel using visible small strokes, which will be the underlying base for the final coats. This coat is applied thickly. The aim of laying the first coat is to obtain a thick, absorbent layer on which to spread the successive coats.
- To avoid problems removing the masking tape at the end of the job, it is best to replace all the tape when the first coat is almost or completely dry.
- When the first coat of Grassello Plaster has completely dried, normally by the next day, you should remove any ridges/reliefs with a spatula or sanding paper. Because Grassello Plaster contains lime and marbles powders of very small granulometric size, the second coat is applied very thinly. If the first coat is not perfectly uniform, the reliefs will be noticeable on the final finish.
- The second coat of Grassello Venetian Plaster is carefully applied with a large metal trowel using less material than in the first coat. Always keep in mind that the aim of this coat is to lay the smoothest and most uniform surface possible, being careful to avoid creating shiny areas. Since shiny areas can cause problems when applying the next coat, it is necessary to work with a light touch, without pressing too hard; maintain a 40° angle with the blade of the trowel. If the application of a single second coat does not give you a smooth, even surface, you should apply another coat immediately before the second coat dries. We suggest applying this additional second coat especially when the desired finish is to have little texture or when you want to achieve a superior, quality job.
- While you can apply the final, third coat as soon as the second coat begins to dry, most people prefer to wait for the second coat to dry completely because of the risk of peeling. Apply the third coat of Stucco Grassello Plaster in a thin layer to small areas (max. 1 square meter) with a medium-sized metal trowel. Normally, you should start high on the wall, on either the right (preferred by left-handed) or the left side (preferred by right-hand people) of the wall. Swiping on one trowel application after another; each time, the trowel swipes should be in a different direction than the previous one so that you obtain a harmonious design. At the beginning of each swipe, the trowel should be at a 30-35° angle to the wall moving toward the plaster you have already laid. As you continue the swiping movement, you immediately remove excess material by changing the angle of the spatula to 40-45° while moving toward the area you have previously laid. In this way, you keep the newly-laid plaster thin enough over the previous applications while polishing the area of contact between the newly-laid plaster and the area you have already polished. Since the material on your spatula dries out over time, occasionally you will need to scrape the thickened material off, disposing of it, and replacing it with fresh plaster.
- To achieve seamless application when moving from one section to the other you need to proceed both horizontally and vertically. Normally, the application should continue until the wall is completely finished. If the wall is large, you will need more than one person to apply the finish; otherwise, you risk leaving unsightly overlapping marks.
- With this coat, proceed to the final polishing, going over the surface repeatedly with a clean metal trowel moved in different directions. Be sure the edges of the trowel blade are always smooth by using P240-360 sandpaper. If 3 people are working, it’s best that 2 people apply the material with a quick polishing and the 3rd person only polishes. Before it dries, finish by buffing it with a soft fabric cloth.
- Important note: While applying the third coat of Grassello Venetian Plaster, but especially during the polishing phase be careful to move the trowel with the back of the trowel directly following in the path of the front of the trowel. That is, the movement of the trowel MUST NOT be perpendicular to the trowel’s handle, but parallel to it. If this is not possible, then the trowel’s movement on the wall should form a 45° angle with respect to its axis (the handle).
- The aim of the third coat is to obtain a smooth and shiny surface. Shiny meaning that the porosity has been reduced as much as possible. You need to understand that when the material begins to dry, it shrinks, opening up micro-pores. The more micro-pores there are, the less shiny the surface of Marmorino Polished Plasters will be. If the third coat is too thick, either by mistake or by necessity (in the case where the previous coat was not smooth enough), the finish might not be shiny enough. To avoid this, it may be preferable to apply the third coat in two layers. First, by applying a quick coat to a square-meter area without polishing, and then by applying another again, this time completing the polishing as described above.
- During application of Stucco Grassello Fine be sure the work area isn’t too damp or warm to avoid problems with application times.
- Once it is completely dry, after at least 24 hours, we suggest using our Natural Bee’s Wax, colored with the same pigment you used for the stucco. It makes a more refined, “richer” finish, and reduces light spots.
- Remember when you are applying our Stucco Grassello Plaster, it should not be too difficult. If it seems too difficult, stop, and try to understand what the problem is.
Protecting Grassello Venetian Plaster
Stucco Grassello Plaster, thanks to its smooth surface, is a finish that doesn’t get dirty easily. However, we advise the following protective treatments.
After a minimum of 24 hours, at least one coat of the following can be applied:
- Natural Bee’s Wax to obtain waterproofing and general protection against dirt. It makes the surface shinier. It is not recommended on Marmorino Polished Plasters of very dark colors.
- Marseille Soap waterproofing. This does not make the surface look shinier and gives a nice peculiar soft touch.
- Mineral Wax: this water-based paraffin wax gives the strongest protection to Grassello Fine has greater waterproofing power. It does not make the finish shiner.