MASTERCOAT PLASTER Instructions
SAFETY FIRST
KEEP OUT OF REACH OF CHILDREN. AVOID EYE CONTACT. SEEK IMMEDIATE MEDICAL ATTENTION IF INGESTED OR EXPOSED TO EYES. AVOID PROLONGED EXPOSURE TO SKIN. WEAR SAFETY GOGGLES AND GLOVES WHEN WORKING WITH PLASTER. WEAR OSHA APPROVED RESPIRATOR WHEN WORKING WITH DRY MIXES OR WHEN SANDING PLASTER. FOR MSDS (MATERIAL SAFETY DATA SHEET), VISIT WWW.VASARIPLASTER.COM
Watch our instructional videos https://vasariplaster.com/pages/videos
GENERAL
Mastercoat is our thickest and heaviest textured plaster with minimal or matte sheen, but can still be troweled smooth if desired. It can used on interiors as well as exteriors with in most environments or can be sealed to prevent weathering or staining. Mastercoat is a required to use as the initial coat for plaster / Tadelakt shower systems. It is used in place of cement based products, as it is highly resistant to cracking in the curing process. It compliments both traditional and modern settings. Mastercoat can be used on large scale areas replacing paint or can be applied on decorative areas. Mastercoat is made with lime, powdered marble and crushed limestone. Color combinations and creative styles are unlimited. Vasari plasters are very environmentally friendly, healthy and its qualities will improve with time. Vasari's hypo-allergenic products will breath with your space absorbing moisture, absorb carbon dioxide and naturally prevent mold and mildew growth. It can be used in conjunction with our other products such as Marmorino, Veneziano, Carrera or Lime Paint. Mastercoat should be applied in a minimum of 2 coats if applying over Vasari Mineral Primer or pre-existing latex paint or primer.
Vasari produces the highest quality lime plaster finishes. Our materials can be combined and applied in an infinite variety of styles and textures. Explore our website to find the best materials for your project.
COVERAGE
2 gallons: 20 square feet per 2 coats
Dry mix (makes 5 gallons): 50 square feet per 2 coats
SUITABLE APPLICABLE SURFACES
Apply Mastercoat over substrates that are clean, cohesive, free of contamination and as follows:
Gypsum Drywall: (Interiors Only) Drywall should be taped and smoothed to a level 3 or higher finish in accordance with Gypsum Association’s GA-214. Use only Mineral Primer or recommended latex or acrylic primers before applying Mastercoat.
Existing painted substrates: Vasari Mastercoat will adhere to previously existing painted surfaces as long as they are latex or acrylic (water based). We recommend scuffing the surface for better adhesion and wiping any dust before plaster application. Use Vasari Mineral Primer or recommended latex or acrylic primers before applying Mastercoat if necessary.
Existing texture: Mastercoat can be applied onto existing heavy texture such textured stucco and even directly over brick. Apply first coat to cover texture. Minor cracking might occur from excessive thickness, which is acceptable as long as there’s no delamination or peeling.
Preparatory work: Mask and protect adjacent surfaces and remove any dust from surface, especially after sanding. Mask about 1mm to 2mm from adjacent surface or trim to allow for thickness of plaster.
Primer: Vasari Mineral Primer (see ‘Mineral Primer tech data’) or Latex or acrylic primer is required over gypsum board, wood and other substrates with uneven suction or moisture absorption. Allow primer to dry before plaster application.
Exterior application: Using Mastercoat, apply directly over painted surface, primed surface or cement stucco system. Vasari Mineral Sealer may be required to prevent potential patina if there is high exposure to water.
Shower / Tadelakt application: Watch video about plastering showers here. Mastercoat is an ideal way to plaster a shower. Use it as the initial base coat for other Vasari plasters, or use it as the finish coat plaster itself. This will give you a coarser look and feel, unless you apply a coat of Marmorino or a smoother plaster on top. Consult ‘Shower Instructions Technical Data Sheet’ for more information on plastering showers. DO NOT USE CEMENT BASED MATERIALS IN PLACE OF MASTERCOAT, AS THEY WILL CRACK AND SHOW THROUGH THE FINISH COAT OF PLASTER.
APPLICATION
Mastercoat can be applied in a matte sheen with minor movement and variation, or can be burnished or smoothed to limestone like sheen and texture. It can also be applied with layers of heavier texture if desired.
1st coat: Using a trowel, apply thin to .5mm to 1mm thick strokes on to surface. First coat can be applied smooth or textured depending on desired look. The plaster can also be rolled or sprayed, and then back troweled. For a smoother finish, after the plaster has dried for 30-60 minutes, it can be flattened with a trowel. Allow at least 24 hours for first coat to completely dry.
2nd coat: Apply multiple thin or textured passes. Apply each pass over the previous only when it has slightly set and is no longer tacky or wet. When the plaster dries to a clay like dryness, after a few minutes, the plaster can then be burnished, or compressed. Keep a wet edge and terminate applications at natural divisions of surface such as control joints or corners.
Matte finish: On last the coat, apply multiple thin passes with the burnishing or compressing the material. As the plaster dries to a clay consistency, do not burnish the plaster. It’s sometimes a good idea to lightly sand the surface with a soft abrasive material like a sanding sponge or 300 grit+ sand paper for a softer suede like feel.
Top coats: If desired, plaster can be finished with a sealer, wax or numerous decorative finishes depending on the desired look and required durability.
Lime Paint / Lime Wash: Vasari Lime Paint can be thinned with water and applied in a thin if not translucent manner on top of Mastercoat for subtle or dramatic decorative color finishes.
Colorants: Colors are sold separately for Dry mix and can be chosen from our color chart. Wet mix plasters are sold pre-tinted. Mastercoat can also be tinted to almost any color. Can be tinted with water based or dry pigments. For pure beautiful white, use untinted Mastercoat. Multiple colors can be applied simultaneously for more creative finishes. Dry mix plasters require one tint packets for 5 gallons of plaster.
As a basecoat for thicker application: Mastercoat is an excellent plaster for smoothing or eliminating particularly rough or textured areas. It can smooth out brick in 2 coats, for example.
SHELF LIFE & STORAGE
Do not store in direct sunlight and protect from extreme heat and cold. Store Vasari Plaster products in a cool, dry place. When properly stored, Vasari ‘wet mix’ plaster products’ shelf life is 5 years from purchase date. Vasari ‘dry mix’ plaster products’ shelf is 2 years from purchase date. Wet mixes should be stored with a generous layer of water on the top of the bucket as to not dry out the material. The plaster might slightly thicken over months and years depending on climate conditions and colorant.
DO NOT FREEZE. If frozen, allow up to 48 hours to thaw, thoroughly mix plaster with a drill, and apply.
CARE AND MAINTENANCE
All Vasari products can be cleaned using water in most instances. Solvents such as paint or lacquer thinner and mild detergents can be used to remove stubborn stains. Do not use acidic cleaners or bleach.
Sealers: Sealers are optional depending on necessary water and resistance. Use Vasari Mineral Sealer for protection against dirt and stains. Use Vasari Wax for more protection or to achieve a higher luster of sheen. Seal exteriors with Mineral Sealer to reduce water stains or patina.
DRY MIXES
Mastercoat is sold in dry mix form only, except for sample quarts. Add plaster to clean water and mix with 1200rpm drill and a 30” paddle mixer until homogeneous paste consistency is reached. Use about 9 quarts of water for every bag of dry mix Mastercoat. Use warm or hot water if you don’t have a 1200rpm mixer.
Plaster will slightly thicken within a few hours or days to a more workable consistency if mixed too thin. Darker colors will require more tint making the plaster thinner, making thickening time longer.
ADDITIONAL INFORMATION
Flame Spread: ASTM E84, rating of 5; UBC Class I. NFPA Class A. Smoke development 0.
Sound: ASTM 423-07; SAA: 0.09; NRC: 0.10. ASTM 90-04; STC:31
Mold Resistance: 0% mold growth, per test results from procedure ASTM D3273-00
Incompatibility: Salt, chlorides, aluminum, hydrogen fluoride and inter-halogens.
Granulation Size Range: 75-150 µm (microns) / 0.15 -0.20 mm
Ph Factor: 11 Ph
VOC & LEED: 0-VOCs, Up to 8 LEED Point Certified.
Hazardous: No known hazardous waste or by-product. No known hazardous decomposition of product or byproducts are known to have occurred.
Health Hazards: Do not ingest or inhale powdered materials for prolonged periods of time. Acute gastric or bronchial irritation will result if ingested or inhaled. Consult your physician if condition worsens or if condition is lasting more than 6 hours.
Flash Point: None
Composition: Custom processed aged lime, powdered marble, particles of minerals and other natural elements make up the composition of Mastercoat. Small percentage organic additives and resins are included to help improve the technical application of the product.
Avoid: Avoid continual contact to the skin and avoid contact with the eyes.
Never add other paints or solvents.
Areas not recommended for Mastercoat: Inside tubs, sinks, countertops and floors. Avoid salt or chlorine exposure.
Dry Time @ 77 °F (25 °C) @ 50% RH – To touch 24 hours. To re-coat 24 hours.
Dries by evaporation, coalescence
Mastercoat weights and measures:
DRY MIX (makes 5 gallons) 50lbs. (22kg.)
1 QUART 3.8 LBS. (2kg.)
WARRANTY
Vasari expressly warranties Mastercoat to be fit for the ordinary purpose for which they are intended for a period of 20 years for non-wet interiors installations, and 10 years for exteriors from date of installation when applied and used in accordance with manufacturer’s instructions within six months of purchase.
WARNING! If you scrape, sand, or remove old paint, you may release lead dust. LEAD IS TOXIC. EXPOSURE TO LEAD DUST CAN CAUSE SERIOUS ILLNESS, SUCH AS BRAIN DAMAGE, ESPECIALLY IN CHILDREN. PREGNANT WOMEN SHOULD ALSO AVOID EXPOSURE. Wear a NIOSH approved respirator to control lead exposure. Clean up carefully with a HEPA vacuum and a wet mop. Carefully clean up with a HEPA vacuum and a wet mop. Before you start, find out how to protect yourself and your family by contacting the National Lead Information Hotline at 1-800-424-LEAD or log on to www.epa.gov/lead
For more technical information, application videos, MSDS, ASTM, LEED, creative design ideas and ordering the best lime plasters, lime paint and tadelakt on Earth, visit WWW.VASARIPLASTER.COM.