How often should you deep clean carpets?

Short answer

Deep clean the carpets every 12 to 18 months. With pets or young children, every 6 months. Deep cleaning means hot water extraction, the machine that sprays solution into the pile and vacuums it back out, and it's what gets the ground-in dirt a vacuum leaves behind. A rental machine and solution cost $30 to $60 and the job takes 120 to 240 minutes for a few rooms. A professional cleaning runs $100 to $300 for the same, and many carpet warranties require one every 12 to 24 months.

Why it matters

A vacuum takes the loose dirt off the top of a carpet. What it doesn't take is the fine grit that works its way down into the pile and the oils from feet, food and pets that bind it there. That grit is abrasive. Every step grinds it against the fibers, and the traffic lanes go dull and matted long before the rest of the carpet wears, which is why a carpet in a hallway looks old while the one under the bed looks new.

Hot water extraction flushes the grit and the oils out. The carpet lasts longer, the lanes stop looking like lanes, and the smells that have soaked into the pile, from pets and spills, come out with the water. It's also what the warranty wants: most carpet makers require a professional hot water extraction every 12 to 24 months, with receipts, or the wear warranty is void.

When to do it more often

Pets or young children: every 6 months. Pets bring in dirt and leave oils and accidents, and children live on the floor.
A carpet warranty: read it. Many require a professional cleaning every 12 to 24 months, and the schedule in the warranty is the one to keep.
Allergies in the house: lean toward the short end, since the pile holds dust and dander that extraction removes.
A spill or an accident: spot clean it right away, and move up the next deep clean if the spot won't come out.

What you need

A carpet cleaning machine, rented from a hardware or grocery store, or a home unit if you have one
Carpet cleaning solution made for the machine

Steps at a glance

Vacuum thoroughly first, in both directions, so the machine isn't fighting loose dirt.
Move the furniture out of the room, or put foil or plastic under the legs of anything that stays.
Pretreat the traffic lanes and any spots with the solution and let it work for a few minutes.
Fill the machine as its instructions say, and work from the far corner toward the door in slow, overlapping passes.
Make a second pass with water only to rinse the solution out, since solution left in the pile attracts dirt.
Open windows or run fans, and keep everyone off the carpet until it's fully dry.

You're done when the traffic lanes match the rest of the carpet and the pile is dry to the touch.

Signs it's overdue

Dull or matted traffic lanes that vacuuming doesn't lift.
Odors that come back after the room is aired.
Stains that reappear after spot cleaning, which means the stain is deep in the pile.
Allergies that flare indoors and ease outside.

DIY or pro

This is an easy job with a rental machine, and the machine does the work. The mistakes are using too much solution, which leaves a sticky residue that collects dirt, and leaving the carpet too wet, which can shrink it or grow mildew in the pad. Go light on the solution, rinse with clean water, and take extra dry passes.

A professional cleaning costs $100 to $300 for a few rooms and brings a truck-mounted machine with far more suction than a rental, which gets the carpet cleaner and leaves it drier. It's what the warranty asks for, it's the better choice for a carpet that's badly soiled or has pet odors deep in the pad, and for a whole house it may cost about what the rental and a weekend would.

FAQ

How often should carpets be professionally cleaned?

Every 12 to 18 months, every 6 months with pets or young children, and on whatever schedule the carpet's warranty requires, which is often every 12 to 24 months.

Is it worth renting a carpet cleaner?

For routine cleaning of a few rooms, yes. A rental costs $30 to $60 with solution and does a good job if you go light on solution and rinse well.

How long does carpet take to dry after cleaning?

Hours with good airflow, longer in humid weather. Fans and open windows speed it up, and a professional machine leaves the carpet drier to begin with.

Does carpet cleaning void the warranty?

The opposite. Most warranties require professional cleaning on a schedule and void the wear coverage without it. Keep the receipts.