Farmhouse Sink Cabinet Prep
Updated February 20, 2026
A farmhouse sink doesn't drop into a standard cabinet like a regular sink. The front apron extends past the cabinet face, and the sink itself is usually deeper and heavier than a standard kitchen sink. That means the cabinet needs modifications: the face frame needs to be cut, the floor of the cabinet needs reinforcement, and the countertop cutout is different. This is mostly carpentry work, and it needs to be precise because the sink weight (a fireclay farmhouse sink can weigh 80-120 pounds) rests on the cabinet, not on the countertop.
Overview
A farmhouse sink doesn't drop into a standard cabinet like a regular sink. The front apron extends past the cabinet face, and the sink itself is usually deeper and heavier than a standard kitchen sink. That means the cabinet needs modifications: the face frame needs to be cut, the floor of the cabinet needs reinforcement, and the countertop cutout is different. This is mostly carpentry work, and it needs to be precise because the sink weight (a fireclay farmhouse sink can weigh 80-120 pounds) rests on the cabinet, not on the countertop.
What to Know
Tools & Materials
- Jigsaw or oscillating multi-tool
- 3/4-inch plywood (for support shelf)
- Cleats and screws
- Level
- Measuring tape
- Shims
- Wood glue and clamps
Step by Step
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Measure the sink and plan cuts
Get the exact dimensions of the sink from the spec sheet. Measure the apron height, overall width, and depth. Mark the face frame cuts so the apron will sit flush or 1/4 inch proud of the cabinet face.
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Cut the face frame
Remove the false drawer panel. Cut the face frame stiles (vertical pieces) and the center rail to accommodate the sink width. Reinforce any cut structural members with blocking behind them.
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Build the support shelf
Cut 3/4-inch plywood to fit inside the cabinet as a raised shelf at the height where the sink bottom will rest. Screw support cleats to the cabinet sides, then set and screw the shelf to the cleats. The shelf must be level and at exactly the right height.
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Set the sink and check alignment
Carefully lower the sink onto the support shelf. Check that the apron front is aligned with the cabinet face and the top rim is level and at the correct height for the countertop. Shim the shelf if needed for perfect alignment.
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Secure and seal
Apply silicone between the sink and the support shelf to prevent shifting. Some installers also use mounting brackets. Make sure the sink is rock-solid with no movement before the countertop goes on.
Pro Tips
- Order the sink before the countertop. The fabricator needs the actual sink (or exact spec sheet) to template the countertop correctly.
- Reinforce the cabinet floor even if you're adding a raised shelf. The extra support prevents the whole cabinet from sagging over time.
- Leave the drain and faucet connections accessible from below. Some farmhouse sinks are so deep that reaching the bottom from above is awkward.
Mistakes to Avoid
- Cutting the face frame before measuring the sink. Even farmhouse sinks from the same brand can vary by 1/4 inch.
- Not reinforcing the cabinet for the sink weight. A sagging cabinet means a sagging countertop seam.
- Setting the sink too high or too low relative to the countertop -- the countertop has to butt up against the sink rim at the correct height.
- Not having the sink on-site before the countertop template appointment.
When to Call a Pro
If you're not comfortable with carpentry or if the cabinet modifications are extensive (e.g., the cabinet is the wrong width and needs to be replaced), hire a cabinet installer. The countertop fabrication should always be done by a pro -- stone fabricators template and cut to the actual sink position.
Bottom Line
Farmhouse sink installation is mostly a carpentry project. Get the support shelf level at the right height, cut the face frame precisely, and make sure the cabinet can handle the weight. Do the cabinet prep before the countertop fabricator comes to template.