Hi all,
We are working through the ResCheck Web Energy Calculator using the 2009 IECC code for our small new home construction project in Wisconsin.

The windows we have for our new construction project are wood with 1/8” single pane low-e coated glass with an exterior wood storm window also with 1/8” single pane low-e coated glass. The windows were made at a small custom wood window manufacturer who provided the U-Value from the glass manufacturer only. A U-Value for the entire window unit is not available. The U-Value from the glass manufacturer indicated In the Window section of the ResCheck a Winter Night U-Value 0.654and Summer Day U-Value 0.501

On the ResCheck Web Energy Calculator for the Window section, it does not offer an option to add storm windows. This is all very new to me, so I’m wondering if someone is able to provide guidance if there is a way to determine a U-Value based on the information I have provided for the window and storm window. Also, if someone is able to provide guidance on how to correctly enter this data in ResCheck. 

Any input, guidance or suggestions would be greatly appreciated.

Thank you!