Most homes in North America are made out of wood—primarily 2x4s and plywood. Stick construction has dominated the housing market for decades, mostly due to the abundance of relatively inexpensive lumber and the ease of building these types of homes.
What is sustainable (or not) about this method? Lumber comes from trees—a natural, renewable product considered to be carbon neutral because they absorb carbon dioxide from the atmosphere before eventually decomposing and releasing that CO2 back into the air. The problem is that wood can expand, contract, and decay—making it a less durable and potentially unhealthy building material. So, the home building industry’s solution to make it last longer has been to chemically treat lumber. But that solution has led to health issues, which has opened the door for new methods of treating wood. Before we tell you what you need to know about thermally treated wood, let’s review the problems with the conventional option.