Because it can really grody, really fast.

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Your bathroom is arguably one of the most important places in the houseto keep clean.

Its a small space often saturated with moisturenot to mention bacteria, dead skin cells, and other germs.

Colorful designer bathroom with shower curtain.

Photo:Chuck Collier/Getty Images

So how do you know when its time to change out an old curtain for a new one?

Ahead, experts offer up their advice for swapping and cleaning shower curtains.

Liners typically keep water in the tub while sparing the curtain from any spraying.

Still, the frequency of washing can help prolong its life.

Ideally, you should be cleaning your shower curtain liner regularly, Carson explains.

Becky Rapinchuk ofClean Mamarecommends throwing the curtain in the washing machine.

Wash it on warm or cool and hang it up in your shower to dry.

Letting it Dry Completely

Do a lot of people use your shower day after day?

You might consider changing out the curtain sooner than six months if the liner is consistently moist from use.

Visible Residue

Mold comes in a variety of colors.

To keep your curtain free of residue in between washes, theres a spray for that.

It really depends on how often you clean it, Rapinchuk says.

If its gross and grungy, toss it!

Youll see when it gets really discolored or moldy, says Dulude.

Then youll know its time for a new liner.