Energy Efficient Windows

The IRS talks about 'windows'

definition of a window: "an opening in the wall or roof of a building or vehicle that is fitted with glass or other transparent material in a frame to admit light or air and allow people to see out." 

to me, a frame is not a window; a glass pane is a window. 

https://www.irs.gov/newsroom/energy-incentives-for-individuals-residential-property-updated-questions-and-answers

Q. What improvements qualify for the residential energy property credit for homeowners?

A. In 2018, 2019 and 2020, an individual may claim a credit for (1) 10 percent of the cost of qualified energy efficiency improvements and (2) the amount of the residential energy property expenditures paid or incurred by the taxpayer during the taxable year (subject to the overall credit limit of $500).

Qualified energy efficiency improvements include the following qualifying products:

• Energy-efficient exterior windows, doors and skylights
• Roofs (metal and asphalt) and roof products
• Insulation

ps: it's not a "deduction" - it is a credit for 10% of the material costs; not labor...not to exceed $2000 (i.e. a $200 credit).

I would say that the work qualifies.  However, you must be aware of:

1. there is a $200 lifetime maximum credit for efficient windows, if you used the credit before, your credit now may be limited.
2. there is a $500 lifetime maximum for all energy efficient improvements, if you used the credit before, your credit now may be limited.
3. the credit for windows is 10% of the cost of materials, not including installation.  If audited, you would need a cost breakdown from your contractor.
4. the panes must meet or exceed Energy Star version 6.0 certification.