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Sink (top to bottom) depth for accessibility.

C

CAR

SAWHORSE
Joined
Feb 14, 2019
Messages
48
Location
Chicago, IL
I've been trying to find clear/direct wording on this. But for some reason I'm not coming up with it on my searches. Is the assumption correct that if one provides a side approach on a commercial project, the sink is not limited to the 7"(top mount) 5 1/2" undermount requirements and could install a taller sink? As long the countertop is at 34" AFF and the counter is 24" deep? Or does the sink have the same requirements, to avoid having a deeper reach inside (even with side approach)?

Thank you.
 
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The 1991 ADAAG and UFAS 4.24.4 limited sinks to 6 1/2" depth. I don't see this in the 2010 ADA Standards for Accessible Design.
 
There is no ADA requirement for commercial project sink bowl depth.

However, forward approach is required by 2010 ADAS 606.2 for both restroom lavatories and for kitchen sinks in kitchens that have a cooktop and/or oven. 2010 ADAS 606.2 requires the forward approach to have knee and toe clearance per ADAS 306, which is 27" AFF at the knees.
2010 ADAS 606.3 requires that the rim of the sink or top of the counter (whichever is higher) not exceed 34" AFF. therefore the maximum bowl depth (including bowl thickness) can be calculated as 34" - 27" = 7 inches. Note that your locally adopted code may be more restrictive than ADAS.

Answering your original question: If it is a kitchen sink AND if the kitchen does not have a cooktop or oven, then 2010 ADAS 606.2 exception #1 allows a parallel ("side") approach to the kitchen sink in lieu of a forward approach. With a parallel approach, knee and toe clearance is not required, and therefore ADAS has no limit on the bowl depth.

If you are doing a forward approach to a kitchen sink, and the sink is equipped with a waste disposal or a very low P-trap, this can often prevent knees and toes from going far enough forward for the hands to reach the faucet controls in their furthest open position, when the faucet is in back of the sink bowls. Using as shallow a sink as possible helps gain more clearance. s

See image below, and picture it with a waste disposal, which exacerbates the problem further:

1692815164394.png
 
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steveray said:
No depth applies that I am aware of....And be careful that the 34" max. is to the rim of the sink, not the countertop....
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Thank you. You're right. I was thinking undermount. Which is why I said countertop. I remember we had to lower an existing vanity in a restroom because the original buildout had a drop in sink that was a half inch above 34".
 
If you're going with a side approach, you don’t have to stick to that strict 7-inch or 5.5-inch sink depth like you would for a front approach. As long as the counter’s at 34 inches high and 24 inches deep, you should be in the clear to use a deeper sink.
 
If you're going with a side approach, you don’t have to stick to that strict 7-inch or 5.5-inch sink depth like you would for a front approach. As long as the counter’s at 34 inches high and 24 inches deep, you should be in the clear to use a deeper sink.
Also, I’d recommend checking out some bathroom taps that are easy to reach from the side since that setup can make it way easier for anyone using it.
 
Tim Mailloux said:
This bit me in the ass once and now I only specify under mount sinks.
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We spec all base cabinet countertops in public housing at 33 1/2" AFF to account for sink rims.
Lately the major cabinet suppliers around here have been using adjustable legs instead of fixed bases, so that they can make height adjustments in the field, prior to applying a base cover plate onto the legs.
 
The 34" limit is measured from the floor at the front of the counter to the top of the sink rim. If the floor slopes slightly from the wall to a drain you can't measure the height at the wall when installing the brackets to support the vanity.
 
Paul Sweet said:
The 34" limit is measured from the floor at the front of the counter to the top of the sink rim. If the floor slopes slightly from the wall to a drain you can't measure the height at the wall when installing the brackets to support the vanity.
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I just inspected a public housing rec room kitchen where this happend. The sink rim is 34 1/8”, and the cabinet sub used fixed bases instead of adjustable legs.
The flooring is vinyl plank. It is cheaper for them to thicken the floor +1/8” than to lower the cabinet bases.
 
Yikes said:
I just inspected a public housing rec room kitchen where this happend. The sink rim is 34 1/8”, and the cabinet sub used fixed bases instead of adjustable legs.
The flooring is vinyl plank. It is cheaper for them to thicken the floor +1/8” than to lower the cabinet bases.
Click to expand...
Been there....Done that....
 
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