Paint and Coatings

Summary

Paint and coatings are pigmented or clear liquid films applied over primed substrates to color, protect, and clean surfaces, in water-based and solvent-based types and a range of sheens. Specify the generic type, MPI gloss level, primer, and VOC limit instead of a brand name or a word like eggshell, since sheen names vary between manufacturers.

Cols

Image

MPI: Master Painters Institute, which publishes product standards and an approved products list
Gloss level (G1 to G7): MPI scale of sheen measured at 60 degrees under ASTM D523
Primer: first coat that seals the substrate and bonds the finish
VOC: volatile organic compound content, in grams per liter
Latex and acrylic: water-based coatings that form an elastic film
Alkyd: oil-modified coating with a harder film, used for trim and high-wear surfaces
PVA primer: polyvinyl acetate primer for new drywall, patches, and joint compound

Standards

Gloss levels

G1, matte or flat: about 0 to 5 gloss units
G2, velvet
G3, eggshell: about 10 to 25
G4, satin: about 20 to 35
G5, semi-gloss: about 35 to 70
G6, gloss: about 70 to 85
G7, high gloss
Manufacturers use different ranges and names, so specify the MPI gloss number

Test standards and rules

MPI: product standards and the Architectural Painting Specification Manual
ASTM D523: specular gloss
40 CFR 59 Subpart D: national VOC limits for architectural coatings, 250 g/L for flat and 380 g/L for nonflat coatings; state and local limits can be lower

Materials

Water-based latex and acrylic: most interior walls and ceilings
Alkyd: trim, cabinets, and high-wear surfaces
Epoxy: strong, wear-resistant coatings for concrete and floors
Polyurethane: tough films that dry quickly
PVA primer: drywall and joint compound

Detailing

Specify the substrate, primer, number of coats, and gloss level for each surface
Match the gypsum board level of finish to the sheen; glossy and dark paints need Level 5
Use sealers and primers made for the substrate, such as masonry, wood, or metal
Check VOC limits, local rules, and any project rating system
Confirm dry film thickness and recoat times on the product data sheet

Uses

Specific uses

Walls and ceilings in all building types
Trim, doors, and cabinets
Steel and metal surfaces
Floors and concrete (epoxy)

Pros and cons

Pros

Low cost per area and easy to change
Wide range of color and sheen

Cons

Shows joints and defects at higher sheens
Needs repainting over time
Surface preparation sets the result

Manufacturing and cost

Construction

Surfaces are cleaned, patched, primed, and finished with brush, roller, or spray in coats
Coats are checked for coverage, sheen, and film thickness

Main manufacturers and suppliers

Trade associations: Master Painters Institute and American Coatings Association.

Sources

UFGS: 09 90 00 painting and coating, MPI gloss levels, https://ufgscriteriadocreport.tpub.com/09900/099000024.htm
Master Painters Institute: standards by group, https://www.mpi.net/Listing_testing/MPI Standards by Group.pdf
Legal Information Institute: 40 CFR Part 59 Subpart D Table 1, https://www.law.cornell.edu/cfr/text/40/appendix-Table_1_to_subpart_D_of_part_59
EPA: architectural coatings national volatile organic compounds, https://www.epa.gov/stationary-sources-air-pollution/architectural-coatings-national-volatile-organic-compounds
Shipshape: interior paint, https://shipshape.ai/help/interior/interior-paint
National Gypsum: five levels of gypsum board finish, https://nationalgypsum.com/ngconnects/blog/building-knowledge/gypsum-board-finish-levels