Frequently Asked Questions (FAQs)

Topics - Commercial - Federal - Manufactured Housing - Multi-Family - Municipal - Residential
Copies of the International Energy Conservation Code (IECC) can be purchased from the International Code Council website. Copies of ASHRAE standards can be purchased from the ...
Topics - building envelope - windows - windows - fenestration - Commercial - sprandel systems - u-factor
Fenestration is considered anything that transmits light, however, COMcheck cannot calculate fenestration without having a wall associated with it. In this case the wall is entirely fenestration therefore, the square footage would be the same for...
Topics - Commercial - Residential - status of state energy codes
Code adoption takes place at the state, and in some cases municipal, level. To determine the code in a particular state, visit the Status of State Energy Code Adoption page.
Topics - Commercial - Residential - code
The IECC addresses mixed occupancies by stating that commercial occupancies must comply with the commercial portion of the code and...
Topics - building envelope - Commercial - software
If multiple users are putting information into COMcheck, each may fill out the appropriate section independently. However, all sections of the building must show compliance to the same code or standard (e.g., cannot show envelope compliance to IECC...
Topics - lighting - lighting - exterior - lighting - interior - Commercial
Exemptions and allowances for lighting are an option that must be activated in COMcheck. To activate the exemptions and allowances, take the following steps: Select either the Interior Lighting or Exterior Lighting Tab Go to the Options menu and...
Topics - addition - alteration - Commercial
COMcheck determines compliance for additions in the same manner as new construction. When entering an addition, only the new portions of the building need to be shown in the software. COMcheck will perform trade-offs between envelope assemblies...
Topics - building envelope - Commercial
COMcheck computes an envelope index that is a reflection of the difference between a 'design' building energy performance factor (EPF) and a 'code' or budget building EPF.  The total building load (made up of cooling, heating, lighting, and...
Topics - building envelope - Commercial
Louvers are best treated as un-insulated portions of the wall. You can add them as a separate wall type (for example, if they are metal, metal building would probably be most appropriate) with no insulation but a wall area. COMcheck will do the...
Topics - windows - Commercial
When entering your fenestration in COMcheck the pop up window has three options to enter your fenestration.  Choose the second option called Product Performance in accordance with NFRC.  If you do not have a pending product number, enter NA and...
Topics - building envelope - Commercial - 40% WWR glazing limitations
The Scope and Application sections of the 2009 IECC address use of ASHRAE 90.1 (2007) as an alternative.  See below for the text.  It is appropriate to use ASHRAE 90.1 as an alternative when your building exceeds 40% glazing, although it does not...
Topics - building envelope - walls - windows - fenestration - windows - glazing - Commercial - calculating above-grade wall area
COMcheck implements the calculation based on the definition of above and below-grade walls in the applicable code.  The calculation for percentage of glazing in ASHRAE Standard 90.1 and the IECC are different as the IECC only looks at above grade...
Topics - Commercial - space conditioning - ASHRAE
ASHRAE’s space conditioning types include: conditioned space, unconditioned or semi-heated space. ASHRAE’s definitions for these types: space: an enclosed space within a building. The classifications of spaces are as follows for the purpose of...