Slow Drain In Your Bathroom Sink?

Once in a while I am asked to look at a slow drain. It often turns out to be a problem of air trapped at the opening of the drain, unable to rise out of the way of the water, which itself backs up at the same opening, unable to get past the trapped air.

Two things cause this to occur. First the aeration of the water at the faucet spout which nicely causes the water to not splash off of the surface of your hand keeping your clothes and countertop neat also softens the impact of the water at the bottom of the fixture. The water which at this time is full of air bubbles weighs less than it normally does and may pool more readily.

Second, the drain opening may impede the flow of water. This happens when a pop-up plunger does not rise high enough or when a drain that is comprised of a number of small holes such as a grid stainer is too close to the center of the flow of water.

Because of this dynamic, when I set up the installation of a lavatory that I know is going to employ a grid strainer I ensure that the water will fall a few inches up the slope of the vessel, and not directly onto the drain center. This allows the water more time to divest itself of air bubbles.

Some pop-up plungers are adjustable and can be made to lift higher when set. Some pop-up plungers are installed so that the full intended throw of the parts is impeded. A grid strainer that is problematically installed may be replaced by a similar drain that has a hand set pop-up.

Fix A Slow Bathroom Sink Drain

If I'm not sure if I have a genuinely slow drain or a plunger not lifting properly, I remove the plunger while I run the water. If this seems to improve the flow I go to another test.

I set the plunger upside-down in the drain opening and fill the fixture to the overflow. When I remove the plunger I hope to see the water swirl down a well-draining fixture. If that happens I switch from trying to clear a clogged bathroom sink drain, to trying to properly set a pop-up.

Don't forget, removing the sink plunger altogether is not advisable. If you remove the plunger, replace it with a hair strainer or other sink stopper that will protect the drain from the typical small objects that get fumbled into the fixture so you do not wind up with a real slow drain.

Back to Clogged Drains