These tools are for informational purposes only. By using these tools you agree not to hold Guliker Design Group Inc. for any discrepancies or errors.

Spatial Calculator

Taken from table of the BC Building code.

Use this calculator to determine the allowable percentage of glazed openings in an exterior wall of a house.

If you are outside of the 10 minute fire response time, you need to divide your limiting distance by 2. If you are outside the 10 minute fire response time and sprinkler your house, you do not need to divide by 2. If you are inside the 10 min. fire response time, and sprinkler your house, you can double your limiting distance. 

If you shrink your browser window, the calculator will change to the mobile version which may be easier to use.


This calculator is based on the trade-off formula (shown below) from of the BC Building code.

Aip / Rip < total Air / Rir and Aip = Air 

– The first line of the spreadsheet is the variable area. 


This calculator is to convert RSI to or from R insulation value.