Notification Window


A step by step guide


An Ontario version of the envelope trade-off software COMcheck is now available for your use. This software replaces the software ENV-STD formerly issued with ASHRAE Standard 90.1, but not issued with the 2010 release. 



COMcheck can be used to demonstrate compliance with OBC 2012, SB-10 January 2014 revision in situations where the designer wishes to propose an alternative to the prescriptive envelope requirements of Division 2 or (3) of SB-10. COMcheck also can be used to demonstrate compliance to the prescriptive requirements for interior and exterior lighting and mechanical system efficiencies. Consult with your local building official with regard to the use of these other features by your consultants.


Any project with a whole building window-to-wall ratio greater than 40% cannot use the Prescriptive Option. These projects are required to demonstrate compliance with SB-10 by the Building Envelope Trade-Off Option of performance calculation method (whole-building energy models, using software such as EE4, eQuest, IES-VE, HAP or TRACE).


Visit to get access to the software;

Select the version of the software appropriate for Mac or Windows operating systems;

Download the appropriate version. 

Web Version

Alternatively, one can use the web version. Go to the URL

Click on "Start COMcheck-Web"

Under the "Code" input in the top left corner, select "Ontario"  (under Local Codes, below North Carolina 2012);

Complete the inputs similar to the stand-alone version.

Stand-alone Program Set-up

The US version of COMcheck has been modified to include the Ontario locations referenced in OBC, but requires a specific set-up on first use. Once the reference code has been identified the program will open each subsequent time using the correct code, unless another code has been selected. Ontario version is current for 2012 OBC and Chapter 2 of DIV.2 of SB-10.

The set-up to establish OBC 2006 SB-10 as the base-line is as follows:

  1. Launch the program on your computer;
  2. From the "Code" menu in the header of the program window, select "Ontario" (in the 3rd section down under 2010 North Carolina)
  3. Gather your project information and convert to inch-pound measures if necessary.
  4. Complete the input tables entering areas of assemblies and their constructions as required.
  5. Build assemblies using the pick lists;
  6. Enter the entire assembly U-value. 

Please note: If not using the assemblies built into the program, this approach one would need to provide supplementary documentation showing the calculated U-value for the assembly. The Canadian program FRAMEplus, or the US DOE programs HEAT and Window6 may be used for verification. Consult with your local building official to establish which program is acceptable.Data that is inputted must be imperial. To convert from metric to imperial a link to a conversion program has been provided under the Code selection menu. Click on ‘Units converter’. To obtain metric data conclusions, use the Units converter to convert the data output from imperial to metric.

Additional Resources

Online training videos and a downloadable manual are now available!

Click here to access the the Building Energy Code Program Online Training videos. No registration is required.

Download a PDF software guide here.


COMcheck User Guide