The Task Group members continued the work to review of the public review comments on Proposed Change 2061 and provide recommendations to the National Model Code Committee on Climate Change Adaptation (NMCC-CCA). 

The Possible Committee Actions (PCA) recommended by the TG in this meeting respond to many of CHBA's comments and those of BILD AB and CHBA-BC including to:

• clarify that the benefits of mechanical cooling would also apply in very hot periods during the shoulder season even though the proposed change says "in the summer months" 
• suggest adding wording to an existing Appendix Note (A-9.1.1.1.(1) that seasonally occupied residential dwellings may be exempt from 'mechanical cooling' because
      ○ they are often located close to other mitigating factors (wind,. shade, lake water)
      ○ they are often uninsulated and installing mechanical cooling is not advisable (cost effective)
      ○ their owners may have access to their primary dwelling with mechanical cooling
• suggest creating an appendix note to explain the difference between 'optional cooling' (design to 24°C for comfort) and 'required cooling' (design to 26°C to reduce the likelihood of heat-related illnesses)
• restate that the policy direction from the Board was to use the NBC to mandate cooling and that therefore portable cooling equipment (i.e. plug-in air-conditioners) were excluded because portable equipment is outside the NBC scope.
• suggest deleting a sentence in an Appendix so as not to suggest that additional airtightness and more thermal insulation are passive measures that could control indoor temperatures. This recognizes that internal gains in very airtight and well-insulated buildings can also contribute to adding to the overheating risk.
• clarify that applications to existing buildings and institutional care facilities were beyond the Board direction given to the committees (which was to develop a solution for new dwelling units only)
• recommend to its parent committee (the NMCC-CCA) to ask the NMCC on Climate Change Mitigation to reflect the mandatory cooling requirement (PCF 2061) in their respective proposed changes on solar heat gain coefficient for windows and peak cooling criteria for energy modeling (PCF 1823)
• revise the wording in an appendix note expressing the acceptable criteria for models in plain language as "models having the capability of predicting indoor temperature and being based on hour-by-hour simulations" rather than referencing ASHRAE 140.

Two more meetings are being scheduled

For more information, please contact Frank Lohmann