Important Information About Your Dryer Vent

Des Moines Air Duct Cleaning is a dryer vent cleaning company that has cleaned thousands of dryers over the last 9 years. In fact, we clean approximately 10,000 per year now. Many of our customers think we are the best dryer vent cleaners around Des Moines and the surrounding area. However, we always see room for improvement. We are able serve our customers best by understanding, applying, and practicing the IRC code Chapter 15 (Exhaust Systems), listed on the International Residential Code .

DSM_dryerAs we see dryer vent lines in question in many older homes, it seems that few contractors are familiar with the codes. We hope that this article will help people understand the codes and distinguish the good from the poor. The dryer’s vent code must be understood. It allows dryers to work properly and safely. This prevents fires that can cause many deaths and millions of dollars each year.

There are Eleven requirements for HTML code that must be followed:

  • Clothes dryers need their own dryer vent lines. It cannot be shared with other appliances, vent fans, chimneys, etc. It must have its vent line separate from everything else.

  • The dryer vent must exit to the exterior of the structure or house. It should not vent into the garage or attic. It should not be vented inside your home! Gas dryers exhaust the carbon monoxide with the dryer air so do NOT vent dryers in the house.

  • Dryer vents need to be located at least three feet from doors and windows. Also, keep them three feet away from the HVAC fresh air intake. The HVAC system can also be damaged by moist dryer exhaust plus lint or the burned gas from a gas dryer could enter the HVAC system. This can pose a threat to your health. 

  • The dryer vent line material must be smooth and made from water-resistant metal. The metal pipe runs from the hookup point on the wall to the exit point. The minimum width of the pipe should be 4 inches and made from 28-gauge steel. For dryer vent lines, do not use flexible transition material.

  • The dryer vent lines must be attached to the structure at twelve feet. These can be done with straps or fasteners that are designed to support them. If the vent is not supported, it can sag and water may build up in the middle. This could cause damage to the ceiling below the pipe.

  • The length of the transition duct (the flexible tube connecting the dryer to the dryer vent in the wall), must not exceed eight feet. The shorter, the better. It can’t be hidden behind a wall, floor or ceiling. It must be visible so it can easily be inspected and, if necessary, replaced.

  • A dryer vent line’s maximum length, measured from the exterior of the structure to the wall, is thirty-five feet. Five feet are taken off for every ninety-degree elbow. If there are two ninety-degree elbows in dryer vent lines, it is considered ten feet.

  • When a dryer vent line is installed in a new building, the person who installed it must leave a copy the manufacturer’s instruction. These instructions will show the maximum length and diameter of the duct.

  • If the dryer vent line length exceeds thirty-five feet in new construction, it must have a permanent label indicating this.

  • After the dryer vent line is installed, and there has not been a dryer for some time, it needs to be closed and marked “future use”

  • Protective plating should be applied to the framing if the dryer vent line is near any other construction.

Clothes Dryer Safety

We offer tips to our customers when we do dryer vent cleaning in Des Moines. The “National Fire Protection Association” has a handy safety sheet that covers dryer safety. Our techs share this info with our customers.

  • Install your dryer by a professional.
  • Check that the dryer has a lint-filter.
  • Fireproof metal transition ducts are recommended.
  • After every load, clean the lint filter.
  • You should ensure that the vent cover flaps are fully open.
  • A professional should inspect your dryer vent line every year.
  • Make sure the dryer is in top condition.
  • Use the correct plug end for your power cord.
  • Follow the manufacturer’s instructions.
  • Do not leave the dryer on when you are leaving the house.
  • You must ensure that the dryer is grounded properly.
  • You need to leave enough airspace around your dryer for good airflow.
  • Don’t dry clothes that have been in contact with gasoline, flammable substances, or any other liquids.


Des_Moines_Air_Duct_Cleaning_Des_Moines_Dryer_Vent_Cleaning_333Failure to clean dryer vent lines is the main cause of dryer fires in home-clothed dryers. You would be surprised at the number of dryer fires each year. Lint builds up in the back of the dryer, the dryer vent line and at the exit point outside. It needs to be cleaned out annually.

Des Moines Air Duct Cleaning takes dryer vent cleaning in Des Moines, Iowa seriously. We train our technicians to inspect the dryer’s ability to exhaust the air that dried the clothes. We also equip them with an air flow tester.

The special instrument is used to measure the air flow coming out of the dryer. The higher the number, the lower the resistance of the air flow. In other words, the higher the number, the better the air flow. A low number means the dryer vent line will have more lint, or the vent cap may be blocked. This will result in a lower air flow. The test tool will show us this and tells us there is a problem. We must fix it.

We check the dryer’s back to see if it has become dirty. The transition tube is also checked to ensure that it is in good condition. We want to ensure that the dryer operates at its highest level and is safe when we leave. Our customers consider us the best dryer vent cleaning service in Des Moines because of our extra effort to keep their dryer operating efficiently and safely.

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