ADU or not ADU, that is the question

[Jack Crabb]

I'm appraising a property with a converted attached-garage area that may or may not warrant classification as an ADU, & I'd appreciate others' thoughts on how they would address the configuration.

The area was reportedly converted from an attached garage to finished living area in 2018. It contains approximately 578 SF & includes a small kitchen/living area, bedroom & full bath, with its own exterior entrance.
The converted area is also internally connected to the remainder of the dwelling through a shared laundry room containing a shared half bath. There are no locks on the doors or other apparent physical separation between the converted area, shared laundry room & primary portion of the dwelling. All areas of the dwelling are on the same electric meter & water supply line.

The assessor continues to identify the converted area as garage; however, the owner reports the conversion occurred in 2018. I've requested the applicable permit/inspection information from the local building department to determine how the conversion was permitted/classified, but they advise that responses may take up to seven days, if indeed it was permitted. The appraisal is currently due tomorrow.

Assuming the permit information is not available prior to completion, I'm interested in how others would approach this, particularly given the unrestricted interior connection & shared laundry/half-bath arrangement.

I've included an image of the sketch showing the existing configuration for reference (the area in question is shaded).

Thanks!

 

[TerryRohrer]

There are a number of citations in this thread that seem to address your situation.

Post in thread 'Basement ADU?'

Aug 17, 2026

Is a finished basement with separate access that includes a bedroom, kitchen and bathroom considered an ADU if there is also unrestricted access from the primary dwelling unit?​

Publication Date: 06/15/2026

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No, a defining characteristic of an ADU is its independence from the primary dwelling unit. In this scenario, the basement does not qualify as an ADU because of unrestricted access to the primary dwelling unit and lack of separation between the units.

Guide reference: Section 5601.2

There is a...

• alebrewer

• 

 

[Jack Crabb]

There are a number of citations in this thread that seem to address your situation.

Post in thread 'Basement ADU?'

Aug 17, 2026

Is a finished basement with separate access that includes a bedroom, kitchen and bathroom considered an ADU if there is also unrestricted access from the primary dwelling unit?​

Publication Date: 06/15/2026

• copy urlCopy Link
• printPrint

No, a defining characteristic of an ADU is its independence from the primary dwelling unit. In this scenario, the basement does not qualify as an ADU because of unrestricted access to the primary dwelling unit and lack of separation between the units.

Guide reference: Section 5601.2

There is a...

• alebrewer

• 

Thanks - Terry! That is helpful.

 

[J Grant]

I'm appraising a property with a converted attached-garage area that may or may not warrant classification as an ADU, & I'd appreciate others' thoughts on how they would address the configuration.

The area was reportedly converted from an attached garage to finished living area in 2018. It contains approximately 578 SF & includes a small kitchen/living area, bedroom & full bath, with its own exterior entrance.
The converted area is also internally connected to the remainder of the dwelling through a shared laundry room containing a shared half bath. There are no locks on the doors or other apparent physical separation between the converted area, shared laundry room & primary portion of the dwelling. All areas of the dwelling are on the same electric meter & water supply line.

The assessor continues to identify the converted area as garage; however, the owner reports the conversion occurred in 2018. I've requested the applicable permit/inspection information from the local building department to determine how the conversion was permitted/classified, but they advise that responses may take up to seven days, if indeed it was permitted. The appraisal is currently due tomorrow.

Assuming the permit information is not available prior to completion, I'm interested in how others would approach this, particularly given the unrestricted interior connection & shared laundry/half-bath arrangement.

I've included an image of the sketch showing the existing configuration for reference (the area in question is shaded).

Thanks!

Regardless of how an assessor classified it or what a RE agent or an owner says, we as appraisers have to classify it the way the appraisal standards/the client requirements. If for regulated loan purpose, reference Fannie on ADU; an expectation of privacy without direct interior access is the standard.

Even if the construction was done with building permits, it does not change the fact that, because of a shared laundry room and shared half bath, there is no expectation of privacy, so the appraiser should not categorize it as an ADU.

It is a finished garage that can be used as a living area. Describe, disclose, and adjust for it as indicated.

 

[Jack Crabb]

Regardless of how an assessor classified it or what a RE agent or an owner says, we as appraisers have to classify it the way the appraisal standards/the client requirements. If for regulated loan purpose, reference Fannie on ADU; an expectation of privacy without direct interior access is the standard.

Even if the construction was done with building permits, it does not change the fact that, because of a shared laundry room and shared half bath, there is no expectation of privacy, so the appraiser should not categorize it as an ADU.

It is a finished garage that can be used as a living area. Describe, disclose, and adjust for it as indicated.

Thanks for your response!

From what I've read, which I feel is quite a lot at this point, Fannie Mae leaves the phrase "expectation of privacy" open to interpretation. I haven't found anything in Fannie's guidance that specifically defines that as requiring a lockable door versus simply having physical separation by a door. That's one reason I came to this forum, to see how other appraisers interpret & approach that particular issue.

In my house, a closed door means privacy regardless of whether or not it's locked...

 

[glenn walker]

Thanks for your response!

From what I've read, which I feel is quite a lot at this point, Fannie Mae leaves the phrase "expectation of privacy" open to interpretation. I haven't found anything in Fannie's guidance that specifically defines that as requiring a lockable door versus simply having physical separation by a door. That's one reason I came to this forum, to see how other appraisers interpret & approach that particular issue.

In my house, a closed door means privacy regardless of whether or not it's locked...

Expectations of Privacy ? That's a new one because hundreds of homes in my area have Jack & Jill shared bathrooms with shared doors in bedrooms. Privacy is having a Lock on the door. Frankly if this isn't a ADU i have no idea if what a ADU even is. What are you going to call it ? Lmao )

 

[Mike Ault]

Expectations of Privacy ? That's a new one because hundreds of homes in my area have Jack & Jill shared bathrooms with shared doors in bedrooms. Privacy is having a Lock on the door. Frankly if this isn't a ADU i have no idea if what a ADU even is. What are you going to call it ? Lmao )

if you can legally rent it out, then it's an ADU. If you can't, then it's "guest quarters". The Santa Ana FHA HOC used to tell people on their website that the "expectation of privacy" doesn't even require a bedroom door, you can simply hang a sheet in the doorway. My standards are a little higher than that, but theirs weren't at the time.

 

[glenn walker]

if you can legally rent it out, then it's an ADU. If you can't, then it's "guest quarters". The Santa Ana FHA HOC used to tell people on their website that the "expectation of privacy" doesn't even require a bedroom door, you can simply hang a sheet in the doorway. My standards are a little higher than that, but theirs weren't at the time.

I have a ADU and anytime someone is living on your property you lose some privacy. Luckily I use it as a Safe Space after Uncle Billy passed but how about bathrooms in Master Bedrooms those certainly don't offer any privacy. Lol )

 

[Mike Ault]

I have a ADU and anytime someone is living on your property you lose some privacy. Luckily I use it as a Safe Space after Uncle Billy passed but how about bathrooms in Master Bedrooms those certainly don't offer any privacy. Lol )

Quite often we used to tear those detached converted garage apartments down because they detracted from the value of the front house for exactly the reason you mentioned.

 

[Tom4value]

I'm appraising a property with a converted attached-garage area that may or may not warrant classification as an ADU, & I'd appreciate others' thoughts on how they would address the configuration.

The area was reportedly converted from an attached garage to finished living area in 2018. It contains approximately 578 SF & includes a small kitchen/living area, bedroom & full bath, with its own exterior entrance.
The converted area is also internally connected to the remainder of the dwelling through a shared laundry room containing a shared half bath. There are no locks on the doors or other apparent physical separation between the converted area, shared laundry room & primary portion of the dwelling. All areas of the dwelling are on the same electric meter & water supply line.

The assessor continues to identify the converted area as garage; however, the owner reports the conversion occurred in 2018. I've requested the applicable permit/inspection information from the local building department to determine how the conversion was permitted/classified, but they advise that responses may take up to seven days, if indeed it was permitted. The appraisal is currently due tomorrow.

Assuming the permit information is not available prior to completion, I'm interested in how others would approach this, particularly given the unrestricted interior connection & shared laundry/half-bath arrangement.

I've included an image of the sketch showing the existing configuration for reference (the area in question is shaded).

Thanks!

I don’t know the the general laws in TN but here in MA, every community has their own laws on ADUs. Some allow them by right, others don’t allow them at all. My own town doesn’t recognize them at all. You have to get a special permit to convert the property from a 1 family to a 2 family (and meet the qualifications). So from where I am sitting, tell the client and ask for an extension.

Fannie Mae qualifications assume that what they want is legal.