If you are referring to your personal residence, home
improvements such as your new roof would not be deductible unless they
are qualified energy efficient
If you make improvements which increase your home’s market value and/or
extend its useful life, you can add to the cost basis of your home, which
may reduce the capital gain when you sell your property.
In addition, you may be able to
deduct the sales tax paid for building materials for a major improvement to the
home if you itemize deductions and choose the sales tax deduction over state income
taxes paid.
See Home Improvements And Your Taxes