HVAC Essentials: How To Install A Dryer Vent

When considering which room in your house can be the most humid, most people probably wouldn’t think of the laundry room. While bathrooms and kitchens tend to be the most common answers, dryers with poor ventilation can quickly turn your home into a veritable rainforest. When all of that displaced moisture from your clothes isn’t properly ventilated, it tends to cause all types of problems, including:

• water damage
• fire hazards
• carbon monoxide buildup

Existing homes outfitted with washer/dryer hookups already have this ductwork in place, and if it is functioning properly, it all becomes a matter of adopting a proper dryer vent maintenance schedule. However, if you just got done building a detached laundry room or wanting to relocate an existing one, it’s important to plan out and properly install a dryer vent.

Getting Started

Before getting to the installation steps and/or causing unnecessary damage to your home, there are a couple of principles to keep in mind:

• The path from the dryer to the outside must be as short as possible, and never be in excess of 25 feet
• Most dryers have a 4 inch opening
• Location is key

To that last point, multiple bends in the ductwork not only make cleaning and proper dryer ventilation nigh impossible, but it also reduces the length you have to work with. The general rule with a maximum of 25 feet is to subtract 5 feet for all 90-degree bends and 2.5 feet for all 45-degree bends. 

For example, a dryer in the basement would require at least one turn to reach the outside, giving you a total of 20 feet of ductwork to work with.

Here is a list of tools you will typically need to install a dryer vent:

1. Power drill
2. Masonry drill bits (for drilling through stucco or concrete)
3. 4-¼ inch hole saw
4. Caulking gun and caulk
5. Tape measure
6. Foil tape
7. 4-inch rigid/semi-rigid duct pipe
8. Hose clamps
9. Dryer vent

Once you have all of the materials, it’s time to get started on installing a brand new dryer vent the right way.

Installing a Dryer Vent

Step 1: Plan the Path of the Vent Pipe

As mentioned above, the shortest path is the best. A straight shot to the outside can never exceed 25 feet. For 45-degree bends, subtract 2.5 feet from that total, and for 90-degree bends, subtract 5 feet. Proper planning will not only allow you to make adjustments as necessary, but will also help prevent you from drilling holes preemptively.

Step 2: Make a 4-¼ inch Hole to the Outside

Using a section of vent pipe, place it in the desired location and draw a circle around it. Drill a pilot hole in the middle of it that goes to the exterior, then double-checking its position. As long as you don’t find any impediments such as wires or plumbing, use the hole saw to cut through wood. If you are drilling through stucco or concrete, use the masonry bits to drill multiple holes around the circle and then tap out the center. Be sure to leave at least a foot of clearance between the vent and the ground.

Step 3: Put the Vent Cap in Place on the Exterior Wall

Outside, install the vent cap into the hole, making sure that it fits. Secure the vent cap with the provided screws, and caulk around the edges to protect it from the elements. Go back inside and attach the vent cap pipe to the dryer duct. Secure the joint with a hose clamp.

Step 4: Connect the Vent Pipe to the Dryer Exhaust Outlet

With the dryer in the preferred location, measure your vent pipe, accounting for all bends, and then cut the required length. Once the vent pipe is in place, attach the dryer tubing to it and secure it in place with a hose clamp. Be sure to secure all joints with foil tape. 

Step 5: Test Your Work

Now that everything is assembled, it’s time to see if it works. Turn on your dryer and go outside to check the vent. If you feel hot air coming out, the installation was a success; however, if you don’t, go back and check the run for leaks.

How FAMCO Can Help

FAMCO is one of the largest suppliers of ventilation products and HVAC accessories in the Pacific Northwest. If you are relocating or installing a new laundry room, we have a wide selection of dryer vents to choose from, including everything from plastic wall vents to copper vents with a damper. If you have any questions regarding dryer vent installation, feel free to get in touch with us. We’ll be more than happy to help.