A proper sink installation includes more than setting the sink in place. It also covers the faucet, water supply lines, shutoff valves, the drain and trap, and a full leak test. A licensed plumber makes sure all of these work together so you do not face leaks or slow drains later.
Key takeaways
- Pick your sink and faucet first, so the plumber can plan the pipes.
- Old shutoff valves and supply lines should be checked or replaced during installation.
- The drain and trap need to be sized and sloped correctly to avoid clogs.
- A garbage disposal or dishwasher adds extra connections.
- A good installer tests everything before leaving.
A new sink can change how your kitchen or bathroom looks and feels. But what is under the sink matters just as much as what you see on top. This guide explains what installation involves, how to prepare, and when to call a plumber.
What does sink installation include?
Installation is more than lowering a sink into a hole. Here is what a full job usually covers.
- Turning off the water and removing the old sink and faucet.
- Checking the cabinet and countertop cutout.
- Setting the new sink and sealing it.
- Installing the faucet and connecting the supply lines.
- Fitting the drain, strainer and trap.
- Connecting a garbage disposal or dishwasher line when needed.
- Testing for leaks and checking water flow and drainage.
Our residential plumbing team handles kitchen and bathroom plumbing upgrades from start to finish.
Which sink type fits your space?
| Sink type | Good to know |
| Drop-in | Rests on the countertop, easy to replace |
| Undermount | Sits under the countertop for an easy-wipe look, needs a strong countertop |
| Farmhouse | Large front-facing basin, needs a cabinet made to hold it |
| Pedestal | Common in small bathrooms, pipes may be visible |
| Vanity sink | Built into a cabinet, hides plumbing |
| Bar or prep sink | Small extra sink that needs its own water and drain lines |
Tell your plumber the sink type before you buy. Some sinks need cabinet changes or extra support, and that can change the plan.
What should you prepare before installation day?
- Choose your sink, faucet and any extras like a soap dispenser.
- Make sure the countertop and cabinet match the sink type.
- Clear out everything under the sink.
- Know where your water shutoff valves are.
- Tell the plumber about any slow drains or past leaks.
- Plan for a short time without water in that area.
If you are not sure which parts you need, ask us before you shop. See our services page for everything we install and repair.
What parts make up your kitchen plumbing?
Shutoff valves and supply lines
These control and carry water to the faucet. Old valves can stick or leak. A new installation is the best time to replace them.
Drain and trap
The curved pipe under the sink is called the trap. It holds a little water to block sewer smells. A poor drain setup can lead to slow draining and clogs. If your kitchen drain is already slow, our kitchen drain cleaning can clear it before the new sink goes in.
Garbage disposal
A disposal needs power and a drain connection. If you want one, tell us before installation so we can plan it. See more on our residential plumbing page.
Dishwasher connection
A dishwasher shares the sink drain. It needs a proper connection to stop dirty water from flowing back into the sink.
What happens on installation day?
When our plumber arrives, we talk through the plan and look at the space. We shut off the water, remove the old sink, then set the new one in place. After that, we connect the faucet, supply lines and drain. Last, we run the water, check every joint for leaks and make sure the sink drains well. We clean up before we leave.
You get a clear price before work begins, and we explain anything unexpected before we continue. You can read more about how we work on our about us page.
What kitchen plumbing problems can we fix at the same time?
- Leaky faucets and old fixtures
- Slow or clogged kitchen drains
- Loose or leaking supply lines
- Broken garbage disposals
- Noisy pipes under the sink
- Low water pressure at the kitchen faucet
If your pipes are very old, you may also want to talk about pipe repair or replacement. A kitchen remodel is a great time to do it. Our hydro jetting service can also clean stubborn grease buildup in kitchen drain lines. If you plan a big remodel and need help with payment, take a look at our financing page.
Where do we offer sink and kitchen plumbing?
We work in Laurel and across Maryland, Washington, D.C. and Northern Virginia. Check our service areas page. We also help homes in Washington, D.C. and Howard County.
Ready for a new sink?
Call Twin Plumbing Solutions at (301) 920-6922 or request a free quote. We will plan the job, install it right and test it before we leave.
Frequently Asked Questions
What is included in a sink installation?
It includes removing the old sink, setting the new one, connecting the faucet, supply lines and drain, and testing for leaks. We can also connect a disposal or dishwasher. See our residential plumbing page for more.
Can I replace a sink without hiring a plumber?
A simple swap in the same spot may be possible if you are handy. But leaks, old pipes or a new layout are better left to a pro. Contact us if you are unsure.
Do I need to buy the sink and faucet first?
Yes, it helps. Knowing your sink type lets the plumber plan the pipes and cabinet space. If you need help choosing, ask us through our contact page.
Can you install a garbage disposal with a new sink?
Yes. We can add a disposal during the same visit. Learn more on our residential plumbing page.
My kitchen drain is slow. Should I fix it before installing a new sink?
Yes. A slow drain can mean a clog or pipe problem that will not go away with a new sink. Our drain cleaning service can clear it first.
Do you offer kitchen plumbing in Laurel, MD?
Yes. Laurel is our home base. See our Laurel service area page for details.
How do I get a quote for a sink installation?
Call us or fill out the form on our contact page. Tell us the sink type and any extras, and we will give you a clear price before we start.