Can you cost segregate an ADU that you built on your primary residence?

[Owen Schwaegerle]

Hi BP Fam,

We are currently doing a garage conversion to an ADU on our primary residence. Adding a lot of value has been great, and rather than take the depreciation over a long period of time we'd like to cost segregate it. Does anyone know if you can cost seg an ADU on a primary?

We are currently house hacking by renting out a 900 SF addition on our house as a midterm rental. Once the ADU is complete we will be midterm renting that as well. We want to make sure to get the highest number of deductions possible since we are on a shared meter. Are we able to deduct the total utilities etc for this home on a % basis of the square footage?

Would love to hear your thoughts!