During this morning’s Technical Committee block, the CMA Technical Subcommittee undertook discussion of two ballots concerning spandrel area, with both going back to Task Group.
Ballot One: NFRC 100-2010 Ballot-Spandrel Considerations
Spandrel systems were included in the NFRC 100-2010, but without specifying how to model them. This ballot would add language and provide material for the Technical Interpretation Policy Committee (TIPC) to instruct the Lawrence Berkeley National Laboratory (LBL) to revise the simulation manual with modeling steps for calculating the U-factors of spandrel panel systems and recommend that CMAST steering committee initiate changes in CMAST to provide functionality to calculated U-factors of spandrel systems.
Jeff Baker (Westlab) presented a negative stating that no proof has been provided that this procedure would validate if tested. Baker moved and Marles McDonald (NCTL) seconded to find the negative persuasive and substantive. This passed by unanimous voice vote.
Ballot Two: NFRC 200-2010 Ballot-Spandrel Considerations
Spandrel systems were included in the NFRC 200-2010, but without specifying how to model them. This ballot would add language and provide material for the Technical Interpretation Policy Committee (TIPC) to instruct the Lawrence Berkeley National Laboratory (LBL) to revise the simulation manual with modeling steps for calculating the U-factors of spandrel panel systems and recommend that CMAST steering committee initiate changes in CMAST to provide functionality to calculated U-factors of spandrel systems.
Tom Culp (Birch Point) presented a negative stating that following consultation with several manufacturers one question that arose was whether a Solar Heat Gain Coefficient (SHGC) calculation is needed for spandrel area. The rationale here is that building energy codes treat spandrel area as a wall, where there are no SHGC requirements.
Additionally, the negative pointed out that while fritted spandrel glass and other opaque infills can be handled in a U-factor simulation where they are treated like clear glass, they are test-only products for SHCG, which causes excessive expense when there is no real demand or need for a SHGC rating for spandrel areas.
Accordingly, the negative recommended that a spandrel area procedure not be included in NFRC 200, and when the U-factor rating for spandrel is completed, the PCP make it clear that SHGC is not a required rating on the label certificate for spandrel area.
Brenden (AAMA) moved, and Mike Barklay (Enermodal) seconded to find the Birch Point negative persuasive and substantive. This passed by voice vote.
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