How To Install A Corner Sink In a Small Bathroom

Posted on: 7 August 2015

If you need to replace a sink, or just need a little more space between toilet and sink, in a small bathroom, you may be considering a corner sink. Although installing a corner sink involves almost the same procedures as installing a regular wall sink, there are a few extra considerations. 

However, if you are physically able to contort yourself enough to work under a corner sink in a small bathroom, it's not really very difficult. Large individuals or those with bad backs should consider choosing a plumbing services provider.

What you will need:

A corner sink

Measure your corner space by width, length, and depth, then check to be sure that the walls are square. If the walls are not perpendicular, you may have trouble with installation or have a gap between sink and wall.

You will need to search for your sink in a plumbing supply store or online, so plan on buying your sink far enough ahead of your installation time.


You will need a small single stem faucet that won't overwhelm your sink, so you may choose to buy and inspect the sink before making your faucet purchase. If the faucet doesn't include supply hoses, you will need to buy hot and cold  water hoses. Check the faucet instruction for the hose size, because a specialty sink may require special hoses.

Sink drain

iIf a drain isn't included with your sink, buy a drain that is one and one quarter inches in diameter.

Pipe tape

Use this for sealing pipe threads

Adjustable wrench



Installing the bracket or clips that will hold your sink

You will install your corner sink with the bracket or clips provided. If you intend to install it in drywall, use a quarter inch bit to make holes in the walls for your bracket or clips per instructions. Insert a drywall anchor into each hole (if anchors are not supplied, you will need to purchase them).

Place the brackets or clips against the holes, and use your drill or a screwdriver to secure the bracket or clips with provided screws.

Place your level on the bracket or clips to check if they are level.

Preparing the sink

it is easier to install the faucet, drain, and hoses before you secure the sink to the wall. Place the supplied brackets and washers in position according to instructions, and  hand tighten the large ribbed plastic nut that will hold the faucet in place. Hand tighten only, because if you tighten it too much, the sink may crack. 

Next, you will apply pipe tape, in a clockwise direction, to the exposed threads of the water connections. Connect the hoses by turning the nuts in a clockwise direction using your adjustable wrench until they are secure.

You can then attach the drain by pushing it through the drain hole, with all washers attached per instructions, and hand tighten the large metal nut that holds it in place. Tighten it securely, but not so much that it cracks the porcelain. No wrench should be used.

Lift the sink and place it on the bracket or clips. Press it down to be sure that it is firmly seated. Use your level to be sure that the sink is level.

Apply pipe tape to the supply pipe threads and attach your hot and cold supply hoses. If you have not moved your sink a considerable distance, which is not likely in a small bathroom, you may be able to reach the sink trap below your sink with your sink drain pipe.

If not, all you need is an adjustable drain pipe extension, which extends and twists in multiple directions. They are made from PVC plastic and cost only a few dollars. Simply slide it over your drain pipe and tighten the upper compression nut (a plastic nut with a washer inside), then stretch it to meet the top of the sink trap and attach it by slipping it inside the trap and tightening the compression nut.

Turn on the water supply and check for leaks. This is the point in the job that may require you to tighten the faucet, hoses, or drain from beneath a small sink in a small corner of a small room. Just remember not to hand tighten the faucet or drain too tightly in an effort to stop a slight leak and finish the job. You make crack the porcelain and all your efforts and expense will be wasted. Contact a local plumber for more info.