Is a utility sink in under-stairs closet code compliant?

[rossn]

I'd like to add a utility/slop sink to be located in the space below a flight of stairs, near the garage. It's currently a closet with some radiant manifolds that aren't in use yet.

In the past, an inspector or contractor mentioned there was a related code violation with such an install. Something around head space may have been mentioned, but I've searched but cannot find any code surrounding clearances that would apply.

I do see:


But, was unable to find a definition for 'lavatory'... I'm not sure if that encompasses a utility sink.

Would an install in this space be code compliant? If not, please let me know the code reference.

I'm on IRC 2015, IPC 2015.

Thanks!!

 

[mark handler]

R305.1 Minimum Height​

Diagram
Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).

Exceptions:

1. For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).
2. The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.

 

[mark handler]

Just a note, you will need access the the Plumbing manifold, after the sink is installed.
How are you going to achieve that? rerunning the manifold to have required clearances?

 

[rossn]

Just a note, you will need access the the Plumbing manifold, after the sink is installed.
How are you going to achieve that? rerunning the manifold to have required clearances?

Hi Mark,

I really appreciate your help and guidance here - thank you so much.

Good questions...

As you can see in the below picture, there is space underneath the landing, as well. There is a door that enters that space from the end, that you may be able to make out in the picture. So, anything behind the sink would be accessible from that area, where there will also be additional plumbing run for the bathroom being added above the garage. Additionally, the lower manifold is around 40", so it would sit higher than the rim of the sink. I am envisioning a free-standing stainless, commercial-type sink in this space. The backsplash would rise above that 40" plane, of the manifold, but they are only a few inches deep, and there would be about 2" between the manifold and free-standing sink (for a 30" wide unit.... a slightly narrower unit could also be considered if that is a dealbreaker.

Based on your first comment, I am taking that the space would need to be 6'-8" - is that correct?

The head clearances in the space look like:
Clearance through doorway: 6' 11-1/2"
Ceiling immediately behind door: 8'-5"
Ceiling at very back (in front of the landing): 4'-6"

The sink could be positioned immediately behind the door (i.e. door must be open to use sink), and the ceiling height at the back plane of the sink assembly would be 6'-8" (assuming 29" deep sink assembly). This placement would render the rear space inaccessible from the position of the camera, but it would remain accessible from below the landing.

Given this updated information, do you think this would be considered acceptable? I believe that fundamentally it meets the intent of the code as it relates to clearance over the fixture and user of it.

One additional note - there will also be an electrical junction box further back on the wall with the manifolds, but it would remain accessible from the space behind the sink. In a worst case scenario, that J-Box could face the opposite side of the wall on the left, though my first preference is to have it in the space shown in the pictures.

Thanks, Mark!!