As we continue to see ‘foil bubble insulation’ used incorrectly as duct insulation, it is time to separate the facts from the fiction.  This is a critical issue as the improper installation of these products often increases the heat loss or gain by a factor of four,...

Part 5: Infiltration and Ventilation Air - Impact on Load Calculation This discussion is the fifth in a series on the design a residential HVAC system in accordance with ACCA Manuals J, D, and S, as requirement by the ICC mechanical and energy codes.  The focus is the...

Part 4: Fenestration Windows, Doors, and Skylights – Impact on Heat Loss and Heat Gain The IECC (International Energy Conservation Code) include this definition: FENESTRATION. Products classified as either vertical fenestration or skylights. Skylight. Glass or other...

Part 3: Thermal Factors R-values, U-factors & SHGCs – Consistency on all Construction Documents This discussion is the third in a series on the code requirements for the designing residential HVAC system in accordance with ACCA Manuals J, D, and S.  The focus here...

Part 2: Manual J Design Conditions In Part one, we introduced a series of discussions on load calculation, duct design, and equipment selection.  In this 2nd Part, we will discuss design conditions, opening with a review of several words and terms, as identified in...

Part 1: Introduction This is first of several discussions in a series on factors impacting residential HVAC design. Manuals J, D and S, the ACCA/ANSI Standards for Residential HVAC Design, are recognized by virtually all current Energy, Mechanical and Building Codes,...