Dryer vent

Do you consider this dryer vent a problem. I reported that this unsupported duct dipping down could collect lint and possibly become clogged. And that a clogged vent line would restrict the air flow from the dryer and if was restricted bad enough that it could possibly cause a dryer fire.
The seller had a local building inspector look at this and he told them that is was not a problem. I just felt that this vent line should be supported or replaced with a metal duct to prevent it from dipping. Is this a problem worth reporting?


you did your job. if they ever have a problem in the future they can go back on the building inspector and not you

Yes, it’s a problem and a potential fire hazard.

Is this a concealed space (crawlspace)? If so, building codes do not allow this type of duct in concealed spaces.

Absolutely call this out as a potential fire hazard, regardless of where it is. I don’t believe a building inspector ever saw this and said it was okay.

With something like 20,000 dryer related fires each year I would bet that some of them were due to vents such as you have there.

:neutral:I recommend smooth metal pipe,no screws at joints and well supported.Matt.

Is that non-metallic (plastic or vinyl) flex duct?

If it is, does the dryer manufacturer state that it is OK to use this? I’ve seen instructions (statements) on dryers that state the warranty is void if anything other than metal is used.

On the new LG steam unites they are requires to have a mechanical 90 off the back or the warranty is void.

“The dryer vent in the crawl space was corrugated, flexible ducting. Today’s standards for new construction specify that corrugated pipe may be used only within the first 8 feet and may not be concealed within construction. The concealed ducts should be rigid metal ducts or equivalent, vented to the exterior of the home. This is recommended for fire safety reasons.”

I’m in full agreement with Jeff. :shock:

Add “plastic” to that (i.e., plastic corrugated, flexible ducting). Plastic is even worse than metal cor-flex.

I completely agree with both of those statements. Poor dryer exhausts is a common cause of fires.

Also add that it needs to be smooth inside metal duct, with joints in the direction of flow, and no protruding sheet metal screws.

Check out this classic one on a brand new +$1,000,000 home … :shock:



How is this amalgam for a narrative?:

Underwriters Laboratories standards 560 and 2158 for clothes dryers require that all dryers listed must specify all metal dryer venting unless otherwise tested. A UL 181 label does not apply to dryer venting. Underwriters Laboratories Inc., an independent testing agency that helps set national safety standards, requires that dryer manufacturers
"include explicit instructions specifying that only rigid or flexible metal duct should be used for exhausting, unless the appliance has been investigated for use with nonmetallic duct."

Maytag and other major dryer manufacturers recommend against the use of plastic flexible duct.
Although plastic flexible duct (cheap and easy to install) might seem like just the thing for exhausting a dryer, it isn’t. This type of exhaust duct, which resembles a plastic-covered slinky toy, is not recommended for several reasons.

The Consumer Products Safety Commission estimates there are 24,000 clothes dryer fires each year in the United States, amounting to $96,000,000 in estimated property damage. Lack of maintenance is the leading cause of dryer fires, and [FONT=Arial]LINT is the leading material to ignite. These fires can be caused by failure of mechanical and/or electrical parts within the dryer itself, improper materials being put into the dryer, and insufficient airflow as a result of improper installation.[/FONT]
Clothes dryers can be a source of home fires. Be sure to check your dryer vent and vent hose regularly for lint accumulation. Lint is an excellent source of ignition for a fire. Vents should be made of rigid metal, because flexible vents can be damaged by heat, age and contact with other objects. All vents need to discharge directly to the home’s exterior.

  • North American-style household clothes dryers are required by manufacturers to be vented to the outdoors using a short length of rigid or flexible metal ducting. Manufacturers recommend that the maximum length of the metal ducting, which varies depending on the number of bends, should not be exceeded. This is clearly stated in the manufacturers installation instructions and the appliances are certified according to this requirement.
    *]It is strongly recommended that plastic ducting not be used. Plastic ducts often collapse causing blockage and lint build up within the dryer. This type of plastic ducting can ignite or melt and will not contain a fire within the dryer

The following narrative, prints automatically in all of my reports. (Of course, I can turn it off when necessary).
Faulty dryer vents have been responsible for thousands of fires, hundreds of injuries, and even deaths. The best vents are a smooth-walled metal type that travels a short distance; all other types should be regarded as suspect, and should be inspected bi-annually to ensure that they do not contain trapped lint or moisture.
Regardless, I identify and comment on very dryer vent, including where it discharges.*

I like it, but I would probably rewrite the first sentence thusly so that you don’t have to check on the statistics and change “hundreds of injuries” to “thousands of injuries” when the time comes (think McDonalds–no longer is it “84 billion hamburgers served”–just “billions of hamburgers served”):

Faulty dryer vents and improper installations have been responsible for fires, injuries, and deaths in our homes.

Or something like that.

A few things to know;





Marcel:) :slight_smile: :stuck_out_tongue:

International Residential Code (which many states have adopted - check your state’s Code) 1501.1

Dryer exhaust ducts shall be independent of all other systems, shall convey the moisture to the outdoors, shall terminate on the outside of the building in accordance with the manufacturer’s installation instructions and shall be equipped with a back-draft damper.
Exhaust ducts shall be constructed of rigid metal ducts, having smooth interior surfaces with joints running in the direction of air flow. Screens shall not be installed at the duct termination. Exhaust ducts shall not be connected with sheet-metal screws or any means which extend into the duct. (Screens and screws can trap lint.)

**Exhaust duct terminations shall be in accordance with the dryer manufacturer’s instructions. **

This is all just fine but does not address the problem I have been having for the past 10 years fighting city hall about dryer vents and their potential fire hazards. About 3 out of every 10 inspections I do have VERTICAL DRYER VENTS. and there is not a thing that I can do about it but inform my clients of the potential problems. I have a group of builders that lay the foot print for a home with no consideration for venting the dryer the utility room will be in the middle of the home no exterior wall to get the vent to. Yes this is one of my pet peeves.

I’ll get the discussion going.

What is wrong with vertical dryer vents?

How you inform your Clients of the potential problems would probably be a good report writing exercise right here…

I am interested in the issues regarding vertical dryer vents as well.

I’ll get the discussion going.

What is wrong with vertical dryer vents?

I do not have to tell you RR what is wrong with verticle dryer vents you have to be dumber than a fence post to ever install one of these animals. They stop up within the first 3 years of life. I have inspected two of them this week and they were both stopped up. You can peck on the duct in the attic and it has a different sound when stopped up than when it is open. I have jumped the bones of the city building inspectors many times over this to no availe. As you can see above there is nothing in the code describing this verticle vent. The city inspectors response was that there must be a provided cleanout of this vent system and I asked what do you consider an approiate cleanout and there response was where the flex line connects to the verticle riser is the cleanout. How many people do you know that removes the dryer and clean this vent. NONE

I do not write two pages on this item to the client just inform them the the vent is a verticle vent and the that the construction of this vent is allowed by the city building code division. That it is a fire hazard and should be cleaned on a regular scheduled perodicty to be determined by the owner depending on the usage of the dryer.