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Establish Rough-In Measurements — Precise Sink Height Marking & Measurement

Beginner3 hours

Part of project

Install a Bathroom Sink: Plumbing & Height Guide · Step 2 of 2

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In this video

Using a tape measure, establish the heights for your pipes coming out of the wall or floor. A common standard is to set the center of the drain stub-out at 14 inches from the finished floor. The AAV vent stub-out should be higher, around 17 inches. The hot and cold water supply lines are typically roughed in at 20 inches from the floor. For a double sink, the water lines are often centered between the two drains. The hot water line is on the left and the cold is on the right.

Goal: Plumbing Pipes Installation (Standard)

  • These measurements are a general guide. Always confirm the requirements for your specific sink, faucet, and garbage disposal model before making final cuts.

Used in this video

  • Tape Measure (brand: none, Tool Type: Measuring Tools) — Measuring the correct height and spacing for all plumbing stub-outs
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FAQs

Beyond a tape measure, what other essential tools will I need for this bathroom sink installation?

You'll typically need adjustable wrenches for plumbing connections, plumber's putty or silicone sealant for watertight seals, a level for proper alignment, and a drill with appropriate bits for mounting. A stud finder is also crucial if you're attaching a vanity or wall-mount sink to ensure secure fastening.

What are the most important safety precautions I should take before starting this sink installation?

Always shut off the main water supply to the bathroom or house before starting any plumbing work to prevent flooding. Ensure you are aware of any electrical outlets nearby and turn off power if needed, and wear eye protection when cutting or drilling. Be mindful of the weight of the sink or vanity when lifting.

What are some common mistakes beginners make during sink installation, and how can I avoid them?

A frequent error is not thoroughly understanding your specific plumbing diagram, leading to connection issues. Neglecting to 'dry fit' all components before final assembly can result in leaks or improper alignment. Always double-check your height markings against manufacturer instructions and local codes before making permanent cuts or attachments.

The project is rated 'beginner' and 3 hours. Is this realistic for someone with no plumbing experience?

While rated 'beginner' and estimated at 3 hours, a first-timer should allocate more time, perhaps 4-6 hours, for unexpected challenges or extra trips to the hardware store. Thoroughly reviewing your plumbing diagram and practicing dry fitting will significantly reduce frustration and help you complete the project successfully.

Transcript
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Now let's talk about laying this thing out. Now we have some standards and of course you've got your waterline here and I've already put my little valves on and a lot of people you might be wondering, well what's the second one? Why you got two hots over here? And typically we wouldn't come out and stuff out with the red. It would be white like this one over here. I didn't rough this one in some of the students did. But let's see what they got on their measurements here. Yep, the drain is supposed to be at 14 and the student event stuff out is supposed to be at 17 but they got 17 and a half. More on a vent is okay. And then your waterlines, they should sit at 20. And this is just what works best for us. I mean we've been doing it for a while.

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