Option 6 Simplified
The new residential energy code has an entirely new options table. That means you need to review each option to evaluate which is the most practical for you. The first five choices specify specific practices or combination of practices that reduce energy use by about 8%. Option 6 allows one to use any combination of building envelope materials or methods as long as it produces the same 8% increase in efficiency. You get to design your own option.
Some have been reluctant to choose this option because it requires some calculation. That is no longer the case: Building Codes Division has a tool on their website that makes the option much easier to use. This tool will do all the multiplication and division for you and even has many types of construction loaded onto pull-down menus to make finding the U-factor of your proposed method even easier.
The tool is an Excel spreadsheet that only needs you to input the areas for each exterior building element and choose the kind of construction you wish to use from the pull-down menu. It will quickly tell you if you pass or fail, and by how much. This feature allows you to easily change a construction detail and instantly see the result, such as what would be gained by improving window U-factors from U-0.30 to U-0.28.
When you find the combination that shows compliance and works for you, simply print the spreadsheet and include it with your permit application.
Your HVAC contractor will also find the results useful so they can properly size the heating and cooling equipment, perhaps allowing smaller equipment than might have otherwise been chosen.
Before choosing one of the other options one should check out this tool. There is a good chance it can save money and/or make compliance easier. Here is a link to the tool: 2017 ORSC Residential thermal performance calculator.