How To Assemble a Dryer Vent Pipe
According to the U.S. Consumer Product Safety Commission, in 1998, clothes dryers were associated with 15,600 fires, which resulted in 20 deaths and 370 injuries. Fires can occur when lint builds up in the exhaust duct. Lint can block the flow of air, cause excessive heat buildup and result in a fire.
A properly installed dryer vent pipe will prevent this threat. The installation process is easy and should take two to three hours. There are three types of vent pipe available: flexible plastic, flexible metal and rigid metal. Rigid metal is the best choice, because it is smooth inside and does not collect lint. Flexible vent pipe is not smooth and lint will build up inside the vent.
Determine the path of the vent pipe. The vent can exit the home anywhere--up through the roof or out through a wall. The shorter the distance and the fewer elbows (or turns) in the pipe, the easier the installation will be.
Measure the distance the vent pipe must travel from the exhaust flange on the dryer to wherever it will exit the house.
Count the number and type of bends the pipe will require.
Determine if the distance of venting is acceptable. According to HGTVPro.com, a 4-inch diameter dryer vent may not exceed 25 feet in total distance because of the air flow a standard dryer produces. For each 90-degree turn in the pipe, add 5 feet to the distance measured in Step 2. For each 45-degree turn in the pipe add 2 1/2 feet to the distance measured in Step 2. For example, a 10-foot run of vent pipe with two 90-degree turns is equal to 20 feet of straight pipe.
Examine the exterior of the house where the vent pipe will exit. Make sure that there is 12 inches of clearance above the ground and from any other object. Make sure there is 3 feet of clearance from any opening in the structure, such as a door, window or vent.
Preparing for Vent Cap Installation
Drill a pilot hole at the point where the vent pipe will exit the house. Use the 1/4-inch paddle drill bit in the electric drill. Drill from inside the house out through the wall to the exterior.
Drill the 4 1/4-inch hole. From the outside of the house, use the hole-saw drill bit in the electric drill. Center the hole-saw drill bit in the pilot hole. Hold the drill firmly and apply steady pressure.
Stop drilling occasionally and clean out the bit. The bit can only accommodate 1 inch of material inside of it.
Slide the vent pipe through the new hole to the outside of the house. Extend the pipe end 1 foot outside the wall.
Place a hose clamp over the end of the vent pipe.
Installing the Vent Cap
Secure the vent pipe to the vent cap by sliding the tube of the vent cap into the end of the vent pipe.
Slide the hose clamp up to the end of the vent pipe and tighten with a slotted screwdriver until snug, but do not overtighten.
Push the vent cap flange snugly up against the siding. Align the flange so that it is level. Screw the four screws into the siding of the house.
Caulk around the vent cap flange where it touches the siding. This prevents water from getting in the house.
Caulk around the vent pipe where it comes through the wall inside the house.
Connecting Vent Pipe to Dryer
Hold the vent pipe at the end with the seam up and gently press in on one side of the seam until it comes free from the other side of the seam. Work the separation back about 5 inches.
Cut a 4-inch section of vent pipe from the end of the pipe. Use the tin snips like scissors and cut all around the pipe 4 inches from the end of the pipe.
Reconnect the seam of the 4-inch section of vent pipe and slide it over the exhaust flange at the base of the dryer.
Slide the other hose clamp over the 4-inch vent pipe and tighten it firmly to the exhaust flange.
Install the 90-degree elbow to the 4-inch vent pipe. The ends of the 90-degree elbow are slightly smaller than the vent pipe and can be inserted firmly into the pipe. Position the elbow so that the unattached end is facing the wall with the vent pipe in it.
Finishing the Connections
Measure from the unattached end of the elbow to the wall where the vent pipe comes through. Determine where to cut the vent pipe and mark it with a pencil. Add about 2 inches to the overall length to accommodate the insertion of the elbow into the vent pipe.
Separate the vent pipe seam until there is enough room to cut the pipe at the pencil mark.
Reattach the seam of the vent pipe and firmly insert the elbow into the end of the pipe.
Things You Will Need
- Tape measure
- Rigid metal duct, 4-inch diameter, galvanized (preferable) or aluminum
- Rigid metal 90-degree elbow (as many as needed)
- Electric drill
- Hole-saw drill bit, 4 1/4-inch diameter
- 1/4-inch diameter paddle drill bit with a 12-inch shaft
- Tin snips
- 2 Hose clamps, 4-1/2 inch diameter
- Louvered exterior vent cap, 4-inch diameter
- Slotted screwdriver
- Exterior grade silicone caulk
- Caulk gun
- If the interior wall you need to drill through is covered with sheet rock, cut out a small piece of the sheet rock where the vent pipe will go. Look inside with a flashlight to see if there are any wires or pipes in the way.
- Wear safety glasses when using power equipment.
- Use caution when cutting rigid pipe. The exposed edges are very sharp and can easily cut you.