An outside dryer vent releases hot, moist air from your clothes dryer to the outside of your home. This helps prevent that moisture from building up indoors, which could lead to mold growth and other problems. Some homeowners wonder if they should cover or cap their outside dryer vent when not in use. There are pros and cons to doing this.
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Quick Answers
– It is generally recommended not to cover or cap outside dryer vents. This can prevent proper airflow and lead to lint buildup.
– Covering vents may help keep out pests, debris, and moisture when not in use. But covers should be removed before using the dryer.
– Proper dryer venting is key to efficiency, drying time, and safety. Blockages can cause fires or carbon monoxide poisoning.
– Regular cleaning is the best way to keep dryer vents working properly. Avoid lint buildup by cleaning the lint trap and venting ductwork.
Should You Cover the Outside Vent?
Some homeowners want to cover or cap their outside dryer vent when not in use to prevent pests, debris, and moisture from getting in. Some covers are marketed for this purpose. But is this a good idea?
According to dryer manufacturers and ventilation experts, covering an outside dryer vent is generally not recommended. Dryer vents are designed to allow continuous airflow whenever the dryer is in use. Covering the vent opening can restrict this airflow, even if the cover is removed before using the dryer.
This disruption in airflow can lead to a lint buildup in the vent over time. Lint is highly flammable, so this buildup creates a fire hazard. It can also cause reduced efficiency and longer drying times.
So while the intentions may be good, covering a dryer vent is not considered safe or advisable in most situations. Proper dryer venting and regular cleaning are better ways to maintain functionality.
The Pros of Covering the Vent
There are some potential benefits to covering an outside dryer vent when not in use:
– Keeps out pests – Rodents, birds, and insects may try to enter or build nests in the vent, which would disrupt airflow. A cover could block access when not in use.
– Prevents debris buildup – Covers can keep out leaves, dirt, and other debris from accumulating in the vent when not in use.
– Stops moisture intrusion – Covers may prevent rain, snow, and moisture from getting into the vent pipe during the off seasons. This moisture can damage venting or require more frequent cleaning.
So the main motivation for covering a dryer vent is to maintain clean airflow and prevent blockages. But experts say there are safer ways to achieve these goals.
The Cons of Covering the Vent
There are also some distinct disadvantages and risks to covering a dryer vent:
– Airflow restriction – Any type of cover has the potential to disrupt normal airflow, even if removed before drying. This can allow dangerous lint accumulation over time.
– Fire hazard – Blocked airflow is a leading cause of dryer fires, which are very dangerous. Anything that risks airflow poses a fire risk.
– Moisture damage – Trapped moisture from covered vents can still damage the venting ductwork over time due to condensation.
– Mold risks – Moisture trapped in the venting system can lead to mold growth, which brings health risks.
– Vent damage – Some covers attach directly to the vent hood outside. This risks over-insertion and damage to the vent components.
– Forgotten covers – There is the risk of accidentally leaving covers on and running the dryer, or new homeowners being unaware.
– CO poisoning – Severely restricted airflow could cause a buildup of carbon monoxide from the dryer combustion.
So covers present many potential downsides. The benefits may not outweigh the risks, according to experts. Proper dryer venting is very important for home safety.
Maintaining Proper Dryer Venting
Rather than covering vents, homeowners should focus on proper venting maintenance. Here are some top tips for maintaining safe, efficient dryer venting:
– Clean the lint trap before every load – This removes built-up lint and allows free airflow.
– Clean the vent ductwork annually – Vacuum or sweep lint from ductwork. Consider professional cleaning services if ducts are long or hard to access.
– Remove blockages – Check for kinks or obstructions in the ductwork that disrupt airflow.
– Confirm adequate vent hood airflow – Test tissue paper or streamers to ensure strong airflow through the outside vent hood.
– Use rigid metal ductwork – Flexible plastic venting can sag and allow dangerous lint buildup. Use smooth 4″ diameter rigid metal throughout.
– Reduce ductwork length – Longer ducts allow more lint accumulation. Install the dryer as close to an outside wall as possible.
– Seal vent connections – Use foil duct tape to seal all joints in the vent system so lint cannot escape into wall cavities.
– Make sure the vent hood flapper opens easily – Test this outside to confirm the flapper swings open fully when the dryer is on.
– Consider installing a safety switch – These devices shut off the dryer if normal airflow is disrupted, preventing fire risks.
With proper dryer vent set up and regular maintenance, covers should not be necessary. Never restrict a dryer’s ventilation system.
Outside Dryer Vent Styles
There are a few common styles of outside dryer vents to be aware of:
Vent Hood Duct Terminal
This is the most common type of cap placed at the outside termination of a dryer vent duct. It has a hood to direct airflow and keep out debris. Models are made from metal or plastic.
| Pros | Cons |
|---|---|
| Directs airflow | Plastic prone to damage |
| Prevents backdrafts | Can collect debris |
Low Profile Vent Hood
This is a more discreet vent hood placed close the wall’s surface. The hood has a flatter cover and attaches near the siding.
| Pros | Cons |
|---|---|
| Less visible | Not as rain/debris resistant |
| Sleek appearance | Close proximity risks damage to siding |
Louvered Vent Hood
This style has horizontal slats or louvers to direct airflow out. They allow airflow while keeping out some elements.
| Pros | Cons |
|---|---|
| Directs airflow | Slats can collect lint |
| Sleek appearance | Less protective from elements |
Box Hood Vent
This is a box-shaped hood with a fitted cover. The cover can be propped open when the dryer runs. It closes tightly when not in use.
| Pros | Cons |
|---|---|
| Cover protects from elements | Bulky appearance |
| Can access inside for cleaning | Cover can fall shut and restrict airflow |
There are a variety of quality vent caps to choose from. Just be sure it allows full unrestricted airflow when open.
Special Considerations for Covering Vents
Covers for outside dryer vents should generally be avoided. But there are a few exceptions where covers may be warranted:
– Seasonal homes – Covering vents when a seasonal home is not in use for extended periods can prevent pest infestations. Just remove them before running the dryer.
– Construction areas – A temporary cover can prevent debris and materials getting in the vent during renovations or repairs. Remove it immediately after.
– Pest control – After thorough vent cleaning, covers may deter persistent pest nesting when not in use. But other pest control methods are preferable.
– Excessive rain – In rainy climates, a cover may help during off seasons if the normal vent hood cannot protect from heavy rain.
– Equipment rooms – Server rooms or laundry rooms with excessive lint may use covers when dryers are off to contain lint.
If covers are used in these situations, choose temporary covers that are easily removable. Never operate dryers without full, unobstructed venting. Even brief cover usage risks lint buildup over time, so cleaning is still needed. Avoid permanent covers.
Conclusion
Outside dryer vents provide critical airflow for clothes dryers. Blocking this airflow with covers is not typically recommended, even when not in use. Limited exceptions exist for temporary cover use in specialty situations.
But in normal circumstances, covers pose too much risk of restricting airflow and allowing dangerous lint accumulation. Maintaining clean and unobstructed ductwork through proper venting, cleaning, and maintenance is far preferable.
Following manufacturer guidelines for venting installation and termination is also critical. With good dryer vent set up and care, outside vent covers should not be necessary. The vent hood itself will provide protection. Focus on keeping ducts debris-free and lint-free for safety. Do not attempt to obstruct a dryer’s venting system with any covers or caps.