1. exterior covering
2. 0.125-in felt building membrane
3. 0.625-in plywood sheathing
4. 5.5-in wood roof rafters @ 24 in o.c.
5. sloped air spaces + mineral fiber batt insulation
6. 0.5-in gypsum wallboard

Roofs with Expanded Polystyrene Insulation Construction:

1. exterior covering
2. 0.125-in felt building membrane
3. 0.625-in plywood sheathing
4. 1-in expanded polystyrene insulation
   
5. 5.5-in wood roof rafters @ 24 in o.c.
6. sloped air spaces + mineral fiber batt insulation
7. 0.5-in gypsum wallboard

Effective R-values:

Note: in the Home Energy Scoring tool metal roofs are modeled as composition shingles.