Layers of Wood and Glue


Plywood seems like a simple technology. It is just alternating layers of wood and glue, right? A wood pulp sandwich. Mmmm, sandwich. Like sandwiches, not all are created equal.

It’s all about the ingredients. I used to only pay attention to the face veneer. What species? What quality? Is it clear or with knots? Rough, smooth or finely sanded? As I think more about this house project, the density of the core layer, the weight of the panel, and the type of glue used have become a consideration. Is the wood certified as sustainably harvested?

Since I am most concerned about indoor air quality (IAQ), the glue has become a real concern. Volatile Organic Compounds (VOCs) – as the name suggests, are something you don’t want, or should seriously reduce, in a building. Glues, adhesives (not the same thing), paint, sealants, fire-retardants, insulation and many other common building materials all can contain VOCs. Some carpets, and even furniture have been known for contributing to acute ill-effects.

An unacceptable accumulation of VOCs in a space is called Sick Building Syndrome by the United States Environmental Protection Agency (EPA). Like new car smell, the off-gassing of some of these materials can be immediately noticeable, take a very long time to finish their bombardment and certainly are not something I want in my new home.

After doing some research on materials, I thought it would be interesting to share this. This weekend I was gathering some components to finish up a dog house project. Of all places, Home Depot carries a series of plywood products under the brand PureBond®, that are formaldehyde-free. These are manufactured by Columbia Forest Products in the U.S.

If you’re considering a furniture, casework or tiny home project and want to avoid the off-gassing nature of this chemical, this might be a good choice. These are CARB P2 compliant and contributes to LEED® EQ 4.4 and other green building standards.


{images: “Buttered Toast Sandwich” – by NPR | “Vegas Strip Burger” – (cc) Sean | other images – by Columbia Forest Products –}