Building Envelope Solutions

A few facts about the energy demands of our built environment:

Data from the U.S. Energy Information Administration illustrates that buildings are responsible for almost half (48%) of all GHG emissions annually.  Seventy-six percent of all electricity generated by US power plants goes to supply the Building Sector.”   Source:  www.architecture2030.org website

NIST (National Institute of Standards and Technology) investigated the impact of envelope air tightness on energy use and concluded, “The annual cost savings are largest in the heating dominated climates with potential gas savings of greater than 40% and electrical savings of greater than 25%.”

The data is pretty clear – the buildings we currently design and construct are poorly insulated, create inherent moisture problems and leak air.

Immediate Impact: Understanding that R-19 = R-7.1

The greatest single change designers can make is to move the insulation package and the air/moisture/vapor barrier package to the exterior of the structure.  In a construction environment dominated by steel stud exteriors, codes have enabled the false sense that R-19 fiberglass in a 6″ steel stud exterior wall actually provides an R-19 basis for the wall.  IT DOES NOT.

ASHRAE 90.1 2007 indicates that the Effective Framing/Cavity R-Value of a 6″ stud cavity with R-19 fiberglass is 7.1.  Simply adding 1″ of DOW insulation to the wall will increase the R-value by 70%!

For an expert analysis of this, read “A Bridge Too Far”, Joseph W. Lstiburek, Ph.D., P.Eng., Fellow ASHRAE.

Implementing Solutions:

There are many ways to build structures suited to client needs, from simple Tilt Wall boxes to high tech rain screen veneers.  Insulation selection and placement, control of moisture and sealing to prevent air movement are now known as critical factors to energy performance and indoor air quality issues.  This page is intended simply as a starting point and to get you thinking in the right direction.  Contact us to discuss your specific application and how we can assist.  The links to the right will take you to some resources, projects and solutions.

Questions to think about . . .

We know that sealing foams such as Great Stuff Pro Windows and Doors is recommended for residential applications to stop air flow around this high leakage area, why do we allow commercial windows and doors to remain paths for leakage?

Why do we design roof systems that we know will be completely thrown out after roughly 20 years when there are sustainable solutions?