What insulation values do I need for my building?

This is one of the most frequently asked questions from our architectural clients. While the question seems straightforward on the surface, the answer depends on a myriad of critical factors. Everything from building materials to climate zone location – including the structure's orientation to the sun – has a dramatic effect on insulation requirements.

However, the most important factor we consider from an engineering perspective is whether the building allows for a prescriptive path or a performance-based calculation method.

Small-scale buildings with individual mechanical, electrical, plumbing, and fire protection systems are more inclined to be designed by a prescriptive approach. This is often more clear-cut, but the prescriptive path requires every component of the building to meet or exceed specific performance standards. For example, the roof may require a minimum R-value of 19.

The performance method is often more complicated and requires advanced calculations because it allows more flexibility and tradeoffs when selecting building materials. Large-scale buildings with numerous systems or diverse purposes present more ways to take advantage of the performance-based compliance method. It works so long as the design of the building as a whole is at least as energy efficient as a comparable baseline or reference building.