How do you calculate the cost of insulation material when the job was sold as a service?

Generally, the labor is part of the price.

 

If this is for a rental house, just list the entire amount paid for the insulation. See Schedule E - Internal Revenue Service for more information

 

If this is something else, what ?

This is for our primary residence.

You would need to get a breakdown from the service provider since they purchased the insulation.

 

Energy Tax Credits: Which Improvements Qualify

Equipment and materials can qualify for the Nonbusiness Energy Property Credit only if they meet the standards set by the Department of Energy. The manufacturer can tell you whether a particular item meets those standards.

For this credit, the IRS distinguishes between two kinds of upgrades.

The first is "qualified energy efficiency improvements," and it includes:

• Home insulation
• Exterior doors
• Exterior windows and skylights
• Certain roofing materials

If this is for the home energy credit on your primary residence, and assuming it qualifies, your cost is the total cost of everything. Materials, labor, delivery charges, etc.  The whole shebang. There is no need or requirement to separate out anything.