Do you really need to clean your dryer vent?

The reason you probably hear so much about dryer vent cleaning these days is that many newer homes have laundry hookups in interior rooms, so dryers must be vented through the roof.

That means longer ducts full of twists, turns, angles and potential sags snaking through the attic. In other words, lint has plenty of places to collect on the condensation left from drying steamy laundry. A blocked vent builds up heat, and a duct full of lint is a recipe for fire.

I learned more about this from an informative and certified dryer vent cleaning technician who came to resolve a problem with my dad's dryer.

Venting about a dryer that didn't vent

Soon after I arrived to stay with Dad for the last couple of months, I noticed that when I ran a load of laundry and dried it, the laundry room got really hot and steamy. That made me wonder whether the vent was blocked with lint. The woman who has been cleaning his house for years does his laundry while she's here, so I asked her if she'd noticed any problems with the dryer. She told me that "these houses aren't built right" and "they put the dryer in the wrong place." She told me with absolute certainty it was not vented out of the house. She was right, I later found out, but not because the builder didn't do his part.

I asked my sister if she knew anything about a problem with Dad's dryer vent. She lives nearby and is frequently at his house. She said she hadn't been told of any problems and that the dryer is vented through the roof because of its location. When I saw pet hair and lint flying around the laundry room the next time I dried my wash loads, I knew something was definitely amiss.

My sister and I eventually pulled the dryer out, but we couldn't pull it too far due to space constraints. All we could see behind it was a lot of lint on the wall.

Why you need a certified dryer vent technician

My dad's home warranty service sent a guy to check out the vent, but when he arrived, he said the duct wasn't full of lint because it had never been connected to the dryer! How could he have known that it was never hooked up? With only a visual and manual inspection of the duct lying on the ground behind the dryer, he said he knew because there was no lint in the duct. He hooked it up and left. But the story doesn't end there.

I noticed with the next small loads of laundry that they now required two cycles to dry. The top of the dryer was getting hot enough to dry wet clothes on it. The next time the cleaning woman was drying clothes, her schedule was thrown off by the extra time the laundry was taking to dry -- until she disconnected the duct and admitted that was how she'd been getting the clothes dry for a long time.

Either the dryer had not been working properly or the vent was clogged. My sister-in-law came to the rescue by calling her dryer vent cleaning service, and here's what we learned:

4 warning signs your dryer vent needs cleaning

1. If the laundry takes more than one cycle to dry, it is usually a vent problem. It typically isn't a dryer malfunction unless the dryer does not get hot.
2. If the top of your dryer is getting really hot, your element could burn out and that's commonly because of blocked air flow in the duct.
3. Water marks or lint collecting on or below the gasket around the opening of the dryer door and lint trap can mean the vent is becoming increasingly blocked.
4. If your dryer is vented through the roof because it's adjacent to an interior wall, there is more likelihood of lint build up and potential blocks. Have the vent on the roof inspected and, if necessary, cleaned once a year, especially if you dry more than five loads per week.

The technician tested the airflow in the duct. He told us good air flow for a dryer duct is 20 mph or more. Ours was about 6 mph when he first measured it. It was 26 mph when he finished cleaning it. The dryer works in record time now.

If you still think that cleaning the vent is just another annoying household maintenance expense, consider that besides causing 15,000 fires annually, a blocked dryer vent wastes energy and money -- as much as $3 per load. A professional cleaning costs about $70. Or you could just disconnect it and let the steam and lint fill your laundry room…