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 enter your proposed values. Note, test results should be submitted with the COMcheck report to verify the values entered.
If the product has not been tested or accredited, choose option 3. The code defaults come directly from the tables within the code. Code defaults use worst case scenario for fenestration values and most defaults do not meet the prescriptive requirements dependent upon climate zone. Best recommendation is to choose fenestration products that are tested and NFRC labeled that have better U-factor and SHGC ratings.