In simpler times, you could build a house with very little insulation. This was possible because of the low cost of energy. It allowed buildings to “breathe” while allowing them to dry out naturally. With rising energy prices, increasing awareness of environmental impacts, and high comfort demands, we cannot build in this fashion any longer. The home construction sector has decided to create the technology that will solve all the problems associated building tightly. The Home Performance movement is a result of this. You can see https://bendhes.com/ for more information.
The fundamental idea is that “a house” is a system. In other words, it’s a collection of systems which interact and affect each others. At the heart of these systems’ interactions is air pressure. Building components like the clothes dryer, exhaust fans, and ventilation hoods all create negative pressures. These systems are required to expel moisture and contaminants from the buildings. Understanding how these pressures interact with other systems in a building is also important. An unbalanced home can worsen the effects of these pressures on appliances. Negative pressures can be dangerous for water heaters and furnaces.
BPI-trained Building Analysts test appliances in Home Performance Assessments under “worstcase” depressurization. This is to ensure that they will not malfunction. Analysts are able to use the blower test in Home Performance Assessments, which allows them to see how much of the building’s air sealing can be done and how tight it should be. After sealing the building, analysts can use the blower to measure any air leakage to ensure natural ventilation.
While high-tech insulation might have very high Rvalues (which are great for energy savings), some varieties don’t breathe. Therefore, experts in home performance must think about how the building will handle moisture so that mold is not a problem.