If your dryer takes two cycles to dry a single load, a clogged vent duct is the most likely cause. Lint accumulates inside the duct over time, restricts airflow, and forces the dryer to run longer and hotter to push the same amount of moisture out. Cleaning the vent once a year typically cuts drying time back to one cycle per load, which translates to real money given how much energy a dryer uses.

The fire risk is just as real. The U.S. Consumer Product Safety Commission links more than 2,900 residential dryer fires a year to failure to clean the vent. Lint is highly flammable, and a restricted duct traps heat that would otherwise escape outside. Both problems have the same fix.

Why a clogged vent costs you money

A typical electric dryer draws around 5,000 watts. At the national average of about $0.17 per kWh, a 45-minute cycle costs roughly $0.64. If a clogged vent doubles your drying time, you're effectively doubling that cost per load. Run 5 loads a week, and you're looking at an extra $83 a year in electricity, just from restricted airflow. Gas dryers are cheaper to run per cycle, but they're not immune: a clogged vent forces the burner to fire longer, so the gas cost climbs too. (You can dig into the full math in our post on how much it costs to run a dryer.)

The other side of this is wear on the machine itself. Dryers that run hot and long due to poor airflow tend to have shorter heating element and motor life. Cleaning the vent is one of the few maintenance tasks that pays you back in both lower bills and fewer repair calls.

Signs your vent needs cleaning now

You don't always need to wait for the annual cleaning if you're seeing these:

Any one of these is reason enough to do the job now rather than wait.

What you need

The main tool is a dryer vent cleaning brush kit with flexible rod extensions. These run $20–$30 on Amazon and are designed to reach duct runs of 12–24 feet depending on how many rods come in the kit. You'll also want a vacuum with a hose attachment to pull the loosened lint out at both ends.

Beyond that: a screwdriver to loosen the duct clamp behind the dryer, and possibly a flashlight. That's it.

Holikme Dryer Vent Cleaning Brush Kit

25-piece kit with 12 flexible rod segments that link together to reach up to 24 feet. Brush attaches to a power drill for faster cleaning, or you can work it by hand. Widely used and consistently well-reviewed for typical residential duct runs.

~$25 Pays for itself after one cleaning
Check Price on Amazon

How to clean the vent duct, step by step

Before anything else, figure out your duct path. Start at the back of the dryer, follow the duct to the wall, and find where it exits the house (usually on an exterior wall or through the roof). Knowing the route tells you how many bends you're dealing with and whether a DIY brush kit is realistic. Two or fewer 90-degree elbows and a run under 20 feet: do it yourself. More than that, or a rooftop exit you can't safely reach, hire a service.

Step 1: Disconnect the dryer. Unplug the power cord (or shut off the gas supply valve if it's a gas dryer). Pull the dryer away from the wall enough to access the duct connection at the back.

Step 2: Disconnect the duct from the dryer. Loosen the hose clamp with a screwdriver and pull the duct free from the exhaust outlet on the back of the machine. Set the flexible section aside.

Step 3: Vacuum the dryer exhaust outlet. Use your vacuum hose to pull out any lint built up right inside the exhaust outlet on the dryer itself. Then check the lint trap housing: remove the trap and vacuum down into the slot with a narrow attachment. Lint accumulates there too and is often missed.

Step 4: Feed the brush into the wall duct. Connect two or three rod sections, attach the brush head, and feed it into the wall opening. Push it in gently while rotating. Add rod sections as you go. You'll feel resistance when you hit a lint accumulation; keep rotating and pushing through slowly. Don't force it past a tight spot, as that can disconnect the rods inside the duct.

Step 5: Work from the outside too. Go to the exterior vent cap and remove the cover (usually two screws or a simple clip). Insert the brush from that end as well. Together, working from both ends dislodges more lint than working from one side alone.

Step 6: Vacuum both ends. Once you've run the brush the full length, vacuum out the wall opening and the exterior cap. You may be surprised how much comes out. Lint that looked like nothing in the duct can amount to a significant clump once collected.

Step 7: Check the exterior flap. With the cap off, look at the damper flap. It should swing freely on its hinge and seal closed when the dryer isn't running. A flap that's stuck open lets cold air in and small animals in; one that's stuck shut is as bad as a clogged duct. Clean off any lint residue and make sure it moves freely.

Step 8: Reconnect and test. Reattach the duct to the dryer outlet, tighten the clamp, push the dryer back into position, and restore power. Run a load and check the exterior cap: the flap should open noticeably and you should feel good airflow from outside. If drying time is still long after a full cleaning, the issue may be elsewhere (see the FAQ below).

Duct material matters more than most people realize

While the dryer is pulled out, take a look at what duct material you have. The ridged, accordion-style foil flex duct is the worst option: every ridge catches lint, it kinks easily, and kinked sections trap heat. If that's what you have, replacing it is worth the hour it takes.

Rigid metal duct (galvanized or aluminum) is the best choice for straight runs. For the short section directly behind the dryer where you need some flex, use smooth-wall semi-rigid aluminum duct rather than accordion foil. It's sold at any hardware store for a few dollars per foot and resists kinking and lint buildup much better.

Keep the total duct length as short as your layout allows. The longer the run, the more resistance, and every 90-degree elbow adds the equivalent of about 5 feet to the effective length. Most dryer manufacturers publish a maximum duct length in the installation manual; staying well under it is worth the effort during any ductwork changes.

How often to do this

Once a year is right for most households. If you have a large family doing 8–10 loads a week, or pets whose fur ends up in every load, twice a year is reasonable. A shorter duct run needs cleaning less often than a long one; a longer run accumulates lint faster because airflow slows down and lint has more time to settle.

Clean the lint screen after every single load regardless. It takes three seconds and keeps the duct cleaner longer by catching the bulk of the lint before it ever enters the duct. If you use dryer sheets, know that their residue can coat the lint screen over time and reduce airflow even when the screen looks clean. Washing the screen with dish soap and warm water once a month keeps it clear.

What a professional cleaning costs and when it makes sense

A dryer vent cleaning service typically runs $80–$150. That's worth paying if your duct run is very long, exits through the roof, or has more than two elbows where a brush kit can't realistically reach. It also makes sense if you move into a home and have no idea when the last cleaning happened, as the professional can inspect the ductwork and flag any connection issues or damaged sections at the same time.

For a straightforward wall-exit installation with a run under 20 feet, the DIY route makes more sense. The $25 brush kit gets reused every year, so after the first use it's essentially free maintenance.

FAQ

How often should I clean my dryer vent?

Once a year is the standard recommendation for most households. If you do more than 5–6 loads per week, or if you have a long duct run (over 15 feet), twice a year is reasonable.

Can I use a leaf blower to clean the dryer vent?

You can blow from the outside cap inward, and it will dislodge some lint, but it tends to compact the clog rather than remove it. A dryer vent brush kit that you can pull back out is more reliable.

What if the vent run is longer than my brush kit?

Most brush kits have rods that extend to 12 or 24 feet when linked together. If your run is longer than that, or has more than two 90-degree elbows, hire a vent cleaning service. Expect to pay $80–$150 for a professional cleaning.

Is flexible foil duct okay to use?

The ribbed flexible foil type traps more lint in its corrugations and is more likely to kink. Rigid metal duct is better where you can use it. If you need a short flexible section behind the dryer, use the smooth-wall semi-rigid aluminum type, not the accordion foil.

My dryer takes two cycles to dry a load. Is the vent definitely the problem?

It's the most common cause, so clean the vent first. If drying time doesn't improve after that, check the lint trap housing (lint buildup below the screen), and then consider whether the heating element or gas igniter may be failing.

In short

Pull the dryer out, disconnect the duct, run a brush kit from both ends, vacuum the loosened lint, check the exterior flap, and reconnect. The whole job takes under an hour and costs $25 for the kit. Do it once a year. If your duct is the accordion foil type, swap it for semi-rigid smooth aluminum while you have the dryer pulled out anyway. That one change makes the annual cleaning easier and the dryer more efficient year-round.

If you want to put the savings in context alongside other appliance costs, our post on the biggest energy wasters in your home shows where the dryer sits relative to everything else. And if you're doing a broader look at your home's efficiency, a room-by-room DIY energy audit is a good next step.

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