ADU conversion to existing building on primary home property
Gregory McCarthyPro Member
Rental Property Investor · Portland, ME · Member since 2026 · 6 posts · 4 votesWe live in a development with no HOA, with approximately 170 lots in the neighborhood. I have a two-story, 1000 square-foot building in in the back of my primary homes property. It's currently empty and has electricity and insulated walls. It also stores our pool filter, pump and equipment for my pool. It was there when we bought the house five years ago and appears the original owner used it as a workshop. We want to turn this into a rental unit, but our we just realized our warranty deed may restrict this. It says the following:
1. These lots shall be used for single family residential purposes exclusively.
2.. No structure shall be erected on these lots except one (1) detached single family residentiai dwelling of not more than (2) stories in height, and such other building
• necessary and subsidiary to same such as a garage
3. No duplex residence, garage apartment or apartment house shall be erected or placed on these lots, and no buildings shall be altered or converted into a duplex residence, garage apartment or apartment house.
I know both our neighbors left and right have in law apartments in their basements, but they're not in a separate building. Are we dead in the water, or do we have any recourse to make this project happen? Any advice is appreciated. Thank you
We live in a development with no HOA, with approximately 170 lots in the neighborhood. I have a two-story, 1000 square-foot building in in the back of my primary homes property. It's currently empty and has electricity and insulated walls. It also stores our pool filter, pump and equipment for my pool. It was there when we bought the house five years ago and appears the original owner used it as a workshop. We want to turn this into a rental unit, but our we just realized our warranty deed may restrict this. It says the following:
1. These lots shall be used for single family residential purposes exclusively.
2.. No structure shall be erected on these lots except one (1) detached single family residentiai dwelling of not more than (2) stories in height, and such other building
• necessary and subsidiary to same such as a garage
3. No duplex residence, garage apartment or apartment house shall be erected or placed on these lots, and no buildings shall be altered or converted into a duplex residence, garage apartment or apartment house.
I know both our neighbors left and right have in law apartments in their basements, but they're not in a separate building. Are we dead in the water, or do we have any recourse to make this project happen? Any advice is appreciated. Thank you
Just sharing perspective from the property management side in Massachusetts. Based on what you shared, the language in the deed is pretty explicit around limiting use to a single-family residence and prohibiting separate dwelling units like garage apartments or converted structures. The fact that the building already exists and was historically used as a workshop helps from a use/history standpoint, but converting it into a separate rental unit is usually where things get tricky. What we often see in similar situations is that basement in-law units sometimes slide through because they’re within the primary dwelling and not considered a second structure, whereas a detached building is viewed very differently. That said, neighbors having in-law apartments can still be relevant context, even if not directly comparable. Practically speaking, the path forward usually involves confirming whether the restriction is actively enforced, whether there’s any amendment or variance process, or whether alternative uses (home office, guest space, storage, etc.) make more sense short-term. Before spending money, it’s worth validating expectations with the town and understanding enforcement risk so you don’t invest into something that can’t be used as intended. From a management standpoint, we always recommend getting clarity first, then working backward into feasibility.
Lucas-Howzer Property Management