Proposes to a) clarify certain provisions related to the application of the thermal envelope criteria; b) clarify and enhance provisions related to heat traps and hot water piping insulation and delete shower flow requirements which are addressed by preemptive Federal law; c) provide enhancements to the heating and air-conditioning equipment and systems provisions, most notably revising the acceptable processes for documenting and verifying equipment efficiency; d) revise requirements related to calculation of thermal properties of building envelope components; e) reference the 1989 edition of the ASHRAE Handbook-Fundamentals to provide consistency for the technical basis of Standard 90.2 and the framing factor criteria in the Handbook.