Kitchen Plumbing Rough-In Cost (2026 Prices)
💰 Cost Breakdown
| Item | Low | Average | High |
|---|---|---|---|
| Basic Kitchen Sink Rough-In (Supply + Drain) Running hot and cold 1/2-inch copper or PEX supply lines and a 1.5–2-inch drain line with P-trap and vent to a single kitchen sink location. Includes stub-outs capped and pressure-tested for the finish plumber. This is the minimum rough-in for any kitchen. | $600 | $1,000 | $1,500 |
| Dishwasher Rough-In Adding a hot water supply line, drain connection (high-loop or air-gap installation per code), and an electrical junction box location for the dishwasher adjacent to the sink cabinet. Most codes require the dishwasher drain to connect to the disposal or sink tailpiece with a high loop to prevent backflow. | $200 | $400 | $600 |
| Garbage Disposal Rough-In Upgrading the sink drain rough-in to accommodate a garbage disposal — larger drain connection, continuous waste fitting if double-basin sink, and electrical box placement. The disposal itself is installed during finish plumbing, but the drain sizing and electrical access must be planned during rough-in. | $100 | $200 | $350 |
| Refrigerator Ice Maker Line Running a 1/4-inch copper or braided stainless supply line from the nearest cold water supply to the refrigerator location. A saddle valve is cheap but code-prohibited in most jurisdictions — a proper tee fitting with a quarter-turn valve is the right way. Short runs (under 10 feet) are straightforward; long runs through cabinets or walls add labor. | $100 | $200 | $350 |
| Gas Line for Range/Cooktop Running a black iron or CSST (corrugated stainless steel tubing) gas line from the existing gas manifold to the range or cooktop location. Requires a gas shut-off valve at the appliance, pressure testing, and inspection. Gas line work must be done by a licensed plumber or gas fitter in most jurisdictions. CSST must be bonded per code. | $300 | $600 | $1,000 |
| Kitchen Island Sink Rough-In Running supply and drain lines through the floor slab or subfloor to a kitchen island location. The vent is the challenge — islands can't vent vertically through a roof, so a loop vent, air admittance valve (AAV), or island vent fitting is required. Slab work (saw-cutting and trenching) adds $500–$1,500 to the cost. | $1,200 | $2,000 | $3,500 |
| Pot Filler Rough-In (Wall-Mounted) Running a 1/2-inch cold water supply line through the wall behind the stove to a stub-out at pot filler height (typically 18–22 inches above the cooktop). Simple if done during open-wall rough-in. Retrofitting into a finished wall adds $200–$400 for wall opening, patching, and tile repair. | $150 | $300 | $500 |
Basic Kitchen Sink Rough-In (Supply + Drain)
Running hot and cold 1/2-inch copper or PEX supply lines and a 1.5–2-inch drain line with P-trap and vent to a single kitchen sink location. Includes stub-outs capped and pressure-tested for the finish plumber. This is the minimum rough-in for any kitchen.
Dishwasher Rough-In
Adding a hot water supply line, drain connection (high-loop or air-gap installation per code), and an electrical junction box location for the dishwasher adjacent to the sink cabinet. Most codes require the dishwasher drain to connect to the disposal or sink tailpiece with a high loop to prevent backflow.
Garbage Disposal Rough-In
Upgrading the sink drain rough-in to accommodate a garbage disposal — larger drain connection, continuous waste fitting if double-basin sink, and electrical box placement. The disposal itself is installed during finish plumbing, but the drain sizing and electrical access must be planned during rough-in.
Refrigerator Ice Maker Line
Running a 1/4-inch copper or braided stainless supply line from the nearest cold water supply to the refrigerator location. A saddle valve is cheap but code-prohibited in most jurisdictions — a proper tee fitting with a quarter-turn valve is the right way. Short runs (under 10 feet) are straightforward; long runs through cabinets or walls add labor.
Gas Line for Range/Cooktop
Running a black iron or CSST (corrugated stainless steel tubing) gas line from the existing gas manifold to the range or cooktop location. Requires a gas shut-off valve at the appliance, pressure testing, and inspection. Gas line work must be done by a licensed plumber or gas fitter in most jurisdictions. CSST must be bonded per code.
Kitchen Island Sink Rough-In
Running supply and drain lines through the floor slab or subfloor to a kitchen island location. The vent is the challenge — islands can't vent vertically through a roof, so a loop vent, air admittance valve (AAV), or island vent fitting is required. Slab work (saw-cutting and trenching) adds $500–$1,500 to the cost.
Pot Filler Rough-In (Wall-Mounted)
Running a 1/2-inch cold water supply line through the wall behind the stove to a stub-out at pot filler height (typically 18–22 inches above the cooktop). Simple if done during open-wall rough-in. Retrofitting into a finished wall adds $200–$400 for wall opening, patching, and tile repair.
📊 Factors That Impact Cost
New Construction vs. Remodel
High ImpactNew construction rough-in with open framing costs 30–50% less than remodel work. In a remodel, the plumber must open walls or floors, work around existing structure, and often reroute existing pipes that conflict with the new layout. Wall and floor repair after remodel rough-in is an additional cost not included in plumbing quotes.
Foundation Type (Slab vs. Crawlspace vs. Basement)
High ImpactSlab foundations require saw-cutting and trenching concrete to relocate drain lines — adding $500–$2,000 to the project. Crawlspace and basement foundations allow drain access from below, making layout changes significantly cheaper. If you're on a slab, keeping the sink in its current position saves the most money.
Pipe Material
Medium ImpactPEX supply lines cost 40–60% less in materials and labor than copper. PEX is code-approved in most jurisdictions and is the standard for new residential construction. Copper remains preferred for exposed runs and some high-end applications. For DWV piping, PVC or ABS is standard and cost-effective.
Number of Fixtures and Appliance Connections
Medium ImpactA minimal kitchen (sink only) is the cheapest rough-in. Each additional connection — dishwasher, disposal, ice maker, pot filler, gas range — adds $100–$600. A fully loaded kitchen with an island sink, pot filler, and gas line can reach $5,000+ in rough-in costs alone.