For simplification, I will make up some numbers, and pretend the room was rented out for 1 full year. In that case, would putting "zero" for personal days due to renting one bedroom of the five bedroom home, result in the IRS not realizing this was my principal residence? It was the only home I owned. I have never owned more than one home, and I continued to use it both to store all my and my son's belongings and furniture, my food, and continued to often sleep in and use the home. We both were just trying to reduce for some days, how much we had to commute. Also, will the new law treats it as non-qualified use - the same as if the entire house was non-qualified use - in such a way that it will affect the amount of capital gain that is taxable when I sell the home? I know that if I owned a home for 6 years, and rented the entire house for 2 entire year of the six years , that generally speaking the gain that can be excluded from tax is reduced then by 33.3%, as it was rented for one third of the time. However, in this case we are talking about renting out just a bedroom and attached bath where I maintained personal use of the rest of the house.
