Sink base cabinet sizes: 30, 33 and 36 inches
The sink base is the base cabinet that holds the sink, the faucet plumbing and usually the disposal. It is the same height and depth as any base, 34½ by 24 inches, but it has no drawer box at the top and no full back or bottom shelf where the pipes go. The standard widths are 30, 33 and 36 inches, and the sink decides which one.
Nominal sizes; always check the manufacturer's spec book for the cabinet and the sink maker's minimum cabinet size for the sink.
Standard sink base sizes
| SKU | Width | Height | Depth | Typical use |
|---|---|---|---|---|
| SB30 | 30 | 34½ | 24 | Small single-bowl sinks, tight kitchens |
| SB33 | 33 | 34½ | 24 | Mid-size sinks |
| SB36 | 36 | 34½ | 24 | The common size for a 33-inch double or large single bowl |
The SKU follows the base cabinet pattern: SB plus the width. The front usually has two doors under a false drawer front, because the sink bowl sits where the drawer would be. Some lines also sell 42- and 48-inch sink bases and sink bases with a tilt-out tray; look them up in the line you sell.
How to pick the sink base from the sink
A common rule of thumb is that the sink base should be about 3 inches wider than the sink's outside width, which is why a 33-inch sink usually goes in a 36-inch sink base. It is only a rule of thumb. Every sink maker publishes a minimum cabinet size for each model, and that number wins: undermount sinks with wide flanges, deep single bowls and sinks with built-in accessories can need more than 3 inches. Read it on the sink's spec sheet before the cabinet order goes out, not after the countertop is templated.
The faucet matters too. A wide faucet with side sprayers and a soap dispenser needs countertop behind the sink, which is set by the countertop and the sink, not the cabinet width.
Apron-front and farmhouse sinks
An apron-front sink shows its front face below the counter, so the cabinet under it cannot have a normal face frame across the top. Manufacturers sell a specific apron-front sink base for this, sized to the common apron sink widths. Using a regular sink base means cutting its face frame on site, which most lines do not cover under warranty. Check which apron sink base your line offers, and order the sink first: the cabinet is sized to the sink, and some apron sinks need extra support inside the box.
What goes next to the sink base
- The dishwasher, usually right beside it, in a 24-inch opening between base cabinets. Keeping it next to the sink keeps the drain and supply lines short through the side of the sink base.
- A drawer base on the other side, often a DB18 or DB24, for towels, flatware and cleaning supplies.
- A window above, in many kitchens. A window does not block the base band, but it can block the wall cabinets over the sink, so the uppers usually stop on each side of it.
How Cabinet Project uses these sizes
The "Starter sizes" line every new company gets includes SB30, SB33 and SB36 at 34½ by 24 inches, at list price 0 until you import your manufacturer's price list. In the layout editor the sink base is a box like any other; a sink is not an appliance, but the dishwasher is: it takes a 24-inch opening in the base band, gets the countertop over it in the drawing, and is never priced. A window placed on the wall blocks the uppers where its height reaches them and never the bases, so the sink base can sit right under it.
See the full chart in kitchen cabinet sizes, the rest of the base cabinets in base cabinet dimensions, and how to measure the wall the sink goes on in how to measure a kitchen for cabinets.
Questions
What size sink base do I need for a 33 inch sink?
Most 33-inch top-mount and undermount sinks call for a 36-inch sink base. The sink maker lists a minimum cabinet size for every model; use that number, not the bowl width.
What are standard sink base cabinet sizes?
The common sizes are 30, 33 and 36 inches wide (SB30, SB33, SB36), 34.5 inches tall and 24 inches deep, the same height and depth as other base cabinets. Some lines sell wider sink bases too.
Where does the dishwasher go relative to the sink base?
Usually right next to it, in a 24-inch opening between base cabinets, so the drain and water lines run a short way through the side of the sink base.