If you run a home-based business or work from a home office, then you can get tax deductions for business-related expenses. For example, if you install a new roof over your house, the roofing cost of the section which covers your work area or home office can be deducted from your annual taxes.
If you have rented out a certain part of your home to someone, then the expense of reroofing that area will be deductible too.