Unless you’re a home construction professional, you likely don’t know what the term “building envelope” means. But as a current or future homeowner, knowing what a building envelope is and how it works can be essential in preventing and recognizing issues. Key components of a building envelope are the foundation, wall assemblies, roofing systems, doors, windows, vents and chimneys. It protects the building and its occupants from the elements and also provides aesthetic appeal. The most important job a building envelope does is facilitating climate control.
The envelope keeps cold or hot air generated from furnaces and air conditioners in the home, which saves on electrical and gas bills as well as helps maintain a comfortable temperature for the home’s residents. Building envelopes can be either tight or loose. A tight envelope lets very little air leak out of the building. There are few air gaps due to specific construction and the use of sealants, caulks and air and vapor barriers. Loose building envelopes are less precise and have more areas where air and moisture can both exit or enter the home.
Aside from increasing energy costs, a loose envelope increases the risk of mold and mildew buildup. Ways to prevent damage or serious energy loss from an existing building envelope is to inspect it often and watch for signs of building envelope failure – such as excess moisture in the home or higher than expected energy bills.