By: Robert Golda, Building Enclosure Associate
As building codes and energy codes continue to advance, especially as they are beginning to align with the latest versions of ASHRAE 90.1, the requirements for higher performing exterior envelopes is becoming the norm on many buildings across the country.
With more stringent U-values, and much lower Solar Heat Gain Coefficients (SHGC) for fenestration systems, the cladding industry is quickly reacting by providing more high performance systems for the typical building stock. In addition, strong research into the effectiveness of air barriers, and the demonstrated cost savings when they are properly designed and installed, continues to highlight the importance of the building envelope and its roll in energy performance.
When you think of the phrase "high performance building envelopes", many people think of double facades, or highly insulating opaque façade areas as seen throughout Northern and Central Europe. However, given the advancements in energy codes, high performance will also be applicable to most new buildings across the country.
Requirements for the continuous air and vapor barrier, together with requirements for continuous insulation within building envelopes will now, even for baseline buildings, be a significant improvement in performance when compared to buildings that were built 5 – 10 years ago. In addition, the lower SHGC requirements for glazing has also spurred advancements into the development of higher performing low-e coatings, which further improve the overall performance of even a typical glazed façade system.
Additionally, the ever-growing popularity of Inverted Roof Membrane Assemblies (IRMA) also allows for significant improvement in roof insulation and the overall longevity of the assemblies.
While we continue to look to our counterparts in Europe for continued developments in the realm of high performance building envelopes, we appear to be on the right track in the implementation of these systems for our projects stateside. With the growing popularity of Building Envelope Commissioning, more and more of these high performance envelope systems are being properly designed and executed, adding to the ever growing building stock for exemplar projects for us to turn to for inspiration as well as lessons learned.