Deductions & credits

Why is TurboTax indicating that I have a taxable gain of $8,584.00 (which is the amount of my depreciations) when I bought my home for $147,000 and sold it for $285,000.00. The gain is less than $250,000.00? I rented out part of my home during the years of 2015-2017. Does that make a difference?