I believe the next big change in building codes will be the widespread use of conditioned attics. The concept is just so logical that it is almost a no-brainer. Here is how it works:Currently, most homes in America utilize a “vented attic”. This involves vents in the soffits and vents high up in the roof to allow airflow through the attic. This of course means the attic will be 0 F on a 0 F day and probably 130+ F on a 100 F day (with high humidity). The only thing that separates those wildly swinging temperatures from your home is typically blown or batt insulation. If you’ve been up in your attic, you probably noticed large gaps in the insulation around can lights, penetrations, etc. This means huge amounts of air are either going out into the attic or getting sucked in to your home. Aside from the massive energy loss/ indoor air quality issue, many people have the HVAC units and ducts in the attic. Imagine how much harder your air conditioner has to work if it is sitting in a room that is 130 + F!
In a conditioned attic, foam insulation is blown onto the backside of the roof sheeting. The thermal envelope moves from the ceiling to the roof rafters and therefore the entire attic is now “conditioned”. Soffit vents and roof vents are no longer needed. Penetrations through the ceiling have no effect, HVAC units and ducts now operate in an environment within a few degrees of the living space below. With this one change, a multitude of problems are solved and the home becomes drastically more energy efficient with better indoor air quality. As a bonus, it is now easier to create a finished living space (if the roof pitch is high enough) or at least more conditioned storage space.