Latex (Acrylic) Paint
Finishes: MATERIALS ENCYcLOPEDIA
Applications for this system
Interior and exterior surfaces
Not suitable for use on:
– Surfaces requiring vapor permeability
Binder (a blend of acrylic, vinyl and/or polyvinyl acetate)
Filler (including calcium carbonate, clay, barite and/or cellulose)
Additives (proprietary recipes protect many additives from being named)
Pigment (titanium dioxide in most paints, other pigments and dyes as required by color formulation)
Ratings Chart for latex (acrylic) paint
The ratings chart shows comparative performance in each criteria category. Click on the tabs below for detailed analysis of each criteria.
- HOW THE SYSTEM WORKS
- ENVIRONMENTAL IMPACTS
- MATERIAL COSTS
- LABOUR INPUT
- SKILL LEVEL REQUIRED
- SOURCING & AVAILABILITY
- INDOOR AIR QUALITY
- FUTURE DEVELOPMENT
Latex paint System
While “latex” is the common name for water-based acrylic paints, naturally derived latex (a milky substance found in certain flowering plants) is not used in the vast majority of household paint. The binder portions of the paint tend to be blends (dispersions) of acrylic (polymethyl methacrylate or PMMA), styrene-acrylic, vinyl and polyvinyl acetate (PVA), with different proportions of those three ingredients based on the paint’s intended use and cost. Fillers, which are inert bulking agents, are used to create a desired viscosity and texture. Pigment almost always includes titanium dioxide to create a white base, and natural or synthetic pigments or dyes to achieve the intended color.
There are different formulations of acrylic paint to suit particular applications. The higher the quality and durability of the paint, the higher the percentage of acrylic. Cheaper, less durable paints have more vinyl and polyvinyl acetate.
Due to a generally high level of environmental impacts and toxicity, this category of finishes would not be included in this book if not for the concerted efforts of a small number of acrylic paint manufacturers making serious attempts to reduce the toxic content of their products and clean up the manufacturing process. A sustainable builder should not consider using acrylic paint unless it is sourced from manufacturers with the highest verifiable standards.
Environmental Impact Rating
Harvesting and Manufacturing — High
Accurately assessing the environmental impacts of acrylic paint is difficult. A large number of elements go into any particular paint formulation, and it is beyond the scope of this book to trace each element from harvesting through manufacturing for such a wide product category.
The US Environmental Protection Agency states “Paint and coating manufacturing operations can produce hazardous air pollutants, including heavy metals. Mixing and cleaning operations can release some toxic air pollutants and volatile organic compounds (VOC). Chemicals in these substances can react in the air to form ground-level ozone (smog), which has been linked to a number of respiratory effects. Pigment grinding and milling emits particle pollution (dust), which can contain heavy metals and other toxic air pollutants.”**
Each stage in the harvesting and production of individual elements of an acrylic paint can have wide-ranging impacts, in particular air and water pollution. While North American regulations have stiffened in the past decade, the industries involved in providing materials for acrylic paint manufacturing and the paint manufacturers themselves are responsible for a wide array of toxic emissions that have serious environmental impacts.
A concerted focus has been placed on reducing the quantity of volatile organic compounds (VOCs) in the final paint product, but high volumes of VOCs are still emitted during production. At each stage of harvesting and production, air and water pollution may be created through off-gassing, cleaning and creation of by-products.
The recent trend toward low- or no-VOC acrylic paint is encouraging, but VOCs are not the only toxins in these paints. Even in “eco-friendly” paints, other dangerous compounds include, but are not limited to, ethyl acrylate, zinc pyrithione, benzisothiazolin, hexanoic acid, tetraethylene glycol, acticide, triclosan, nepheline syenite, methylchloroisothiazolinone and vanadium pentoxide.*
It is incumbent upon homeowners making an attempt to purchase acrylic paints with the smallest environmental impacts to do thorough research and distinguish between the claims of manufacturers that are greenwashing and those that are making real efforts to minimize impacts.
Transportation — Low to High
Check manufacturer proximity to job site and distribution network to ascertain impacts.
Installation — Moderate to High
Although acrylic paints are water-soluble, cleanup from application will have environmental impacts. Wash water sent to municipal wastewater facilities or septic systems can contaminate large volumes of water, requiring significant cleaning efforts or resulting in the dispersion of chemicals into the environment. In some municipalities, discharging paint-contaminated water into the sewage system is illegal, and in others it is encouraged as an alternative to dumping in storm sewers or the ground. In either case, contamination is likely to end up in the environment.
Hazardous Waste — All empty containers and used brushes, rollers and cleanup water should be taken to a hazardous waste recovery site.
Material costs: moderate to high
Labour Input: low
Most acrylic paint requires a two-coat application, with application labor similar to other brushed or rolled coatings.
No-VOC paints greatly reduce health effects for applicators. See manufacturer labels and MSDS sheets for specific product information.
Skill level required for homeowners
Preparation of substrate — Easy
None typically required.
Application of finish — Easy
Brushed and/or rolled application.
Sourcing & availability: Easy
Acrylic paints are widely available from paint specialty shops and building supply outlets. Nontoxic acrylics are not widely available, and may be sourced directly from the manufacturer or from sustainable building supply outlets.
Formulations for acrylic paints make them the industry standard against which other finishes are compared. Lifespan can be fifteen to forty years. Additional coats can be applied.
Indoor air quality: low to high
Any quantity of VOCs in acrylic paint will have a negative effect on IAQ, and for this reason only no-VOC paints should be chosen. Be aware that even a no-VOC designation does not mean there are absolutely no VOCs being released in the home. VOCs are not the only compounds that may off-gas from acrylic paint, and it is in the area of these potential air contaminants that the new breed of acrylic paints will have varying impacts depending on manufacturer. A homeowner concerned about IAQ will need to carefully research each brand of paint to determine what toxins may be in it and what risk of air contamination from those toxins may exist.
Resources for further research
Pharos Project database, see pharosproject.net
Fact sheets on reducing air pollution from paint and coating manufacturing issued by the US Environmental Protection Agency, see epa.gov/oaqps001/community/details/paint_manuf.html#4
Acrylic paints and manufacturing processes have been improved quite dramatically in the past decade, and efforts continue to be made by some manufacturers to work toward ever-cleaner paints. The result may eventually be acrylic paints that contain no harmful chemicals and are safely biodegradable, but it is equally possible that dangerous content can be minimized but never fully eliminated. Natural chemistry may provide solutions that are new formulations of existing sustainable finishes. This is an area in which the near future is likely to see a significant amount of change.
Tips for a successful latex (acrylic) paint finish
Acrylic paints are proprietary products. Follow the manufacturer’s instructions for successful application.