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Equipping Dryer With an Exterior Duct Can Eliminate Mildew, Lint


Remember the time you painted the bathroom and about a month later the mildew started to show up again on the ceiling?

Have you ever had to scrape out the caulking from your shower because the mildew was so deeply embedded in the joint you couldn't bleach it away?

Are the bedroom closets beginning to smell a bit musty?

Is mildew growing somewhere in your home?

If the answer to any of these questions is yes, read on.

Mildew is everywhere. It's in the air--all around us. And the minute it comes into contact with any kind of moisture, it begins to multiply exponentially after about two hours. As it multiplies, it becomes visible as a soft blanket of black or green fur that begins to cover everything in its path.

Mildew gets the liquid refreshment when steam in a shower hits the surrounding walls and ceilings and condenses, when steam from cooking hits the surrounding walls and ceilings and condenses, and when steam from the clothes washer hits the surrounding walls and ceilings and condenses.

Problem Can Be Easy to Solve

Starting to get the picture? This same kind of condensation can occur when the clothes dryer is not ducted to the exterior.

The damp exhaust from a dryer condenses upon contact with cold surfaces, such as walls and ceilings.

This problem isn't difficult to solve. All you need to do is duct your dryer to the exterior, which will also solve a lint-in-the-home problem.

If your dryer already is ducted, make sure the duct is clean and clear. According to the National Fire Protection Agency, clothes dryers cause an estimated 14,000 home fires each year. And the leading cause of dryer fires is clogged ducts. So if you are installing a duct, do it properly and keep it clean.

Here are some tips for installing an efficient and safe dryer duct:

* Dryer ducts must be a minimum of 4 inches in diameter.

* The ducts can be flexible in locations where it can be accessed (attic, basement, crawl space) and should be the foil or aluminum type--not the plastic kind.

* Ducts must be rigid in inaccessible areas (as when built into a wall or between floors).

* The male joint of each section should connect in the direction of the flow.

* The duct must be dampered at the exterior.

* All joints should be secured with metal tape (the shiny silver kind)--not duct tape.

* No length of concealed rigid duct should exceed 25 feet.

Deduct 5 feet for each 90-degree turn and half that amount for each 45-degree fitting (example: a concealed rigid duct with one 90-degree fitting should not exceed 20 feet; 25 feet minus 5 feet is 20 feet). Lengths may vary, depending on local codes and manufacturers' specifications.

* Keep in mind that dryer vents must not be combined with any other vent system or chimney of any kind.

Whatever you do, don't duct your dryer into the attic, garage, basement or crawl space. You will create a fire hazard and a stinky, hard-to-access, mildewy mess.

To install the duct, all you have to do is secure enough pipe and fittings to do the job, and cut to length as necessary. Tin snips (metal scissors) make light work of the task. And don't forget heavy leather gloves. Freshly cut tin can be sharper than a jagged piece of glass.

Use 1-inch-wide strips of tin to secure the pipe in place off the ground. Wrap the tin strap fully around the duct and nail the two loose ends to the framing.

Finally, don't forget to test your duct work on a regular basis. It's easy.

While the dryer is running, go outside and get up close to the exhaust damper. Is it open and is air gushing out or does the flow seem restricted? If the latter is the case, a cleaning is in order. You can do it yourself or hire it out, but don't use your dryer when the duct is partially clogged.

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