Trying “Things” Out

The final air sealing scope of work was developed through blower door tests and physical trial and error.  The team developed a DRAFT air sealing scope of work.  It then implemented that draft scope of work in an unoccupied model apartment.  A follow up blower door test was completed.  With contractor feedback and the results of the blower door test in hand, the air sealing spec was improved, retested, and then finalized.  Because  air sealing results in over forty percent of the heating savings, this iterative process of experimenting, retesting, and refining was crucial to the success of the project.

Here are the final air sealing inspection and blower door test checklists:

Air Sealing Inspection Apartment Checklist

Blower Door Test Inspection Checklist

During design, air sealing concepts were actually installed in vacant apartments to see if they would work. A blower door test was used to determine if air sealing goals would be met with the installed air sealing measures.  The blower door test also helped the team prioritize which measures created the greatest reductions in air leakage.  The other benefit of actually installing the designed measures when they were still in “draft” form was that the contractor could help the designers figure out how to tweak the design to make it easier to install and save money.

Among many other measures, Building Science Corporation tested how effective the air sealing was at the joint between the demising wall and the exterior wall.


During exploration in the vacant apartment, it was discovered that once the medicine cabinet was removed in the bathroom, access was gained to a large pipe shaft that was causing major air leakage between apartments. Uninsulated hot water pipes were also clearly visible in this shaft.


During design, a contractor even installed a mockup of the super insulated panel to see how it would work, so that the design could be refined. Here, the panel insulates the wall and also serves as the roof parapet.