Need to vent?
How to hook up a stove vent yourself

So you’re tired of the hood over your stove with a fan that simply sucks up the air and spits it back out. Or maybe you’re lucky enough to get a good deal on a Jenn-Air with a built-in grill or some other type of stove that requires a vent to send all the smoke and smells out of the house.

Well, it’s not as complicated as it sounds, says Mike Frentz.

If you’re really lucky, your stove will be situated on an outside wall in the kitchen. Then all you have to do is install a vent on the wall behind the stove and connect a flexible aluminum pipe to it.

If you’re like a recent customer, on the other hand, things could be a bit more complicated. Her stove is situated against an inside wall while one side faces the walkway through the kitchen to the basement. While there is no exterior to run a vent out, the project is still a feasible and relatively easy one.

Before we get to the how-to’s, here are a few things Mike says to consider before installing a vent to work with your stove:

• If you can, try to place the cook top on an outside wall to minimize the ducting.
• No matter what the route, try to reduce the number of fittings needed that change the duct's direction, shape or area. These all slow airflow and increase the noise. 
• Ideally, the hood or exterior vent cover should have an effective damper to stop the cold air and obnoxious critters from coming in the vent when the fan is not operating.
• Never terminate the vent in an attic. In cold weather, the warm moist air condenses and encourages mold and wood decay.
• An exterior mounted fan is typically quieter than one mounted in the hood.
• For relatively low cost (assuming your house isn't made of brick or stone), plan for the stove to be against an outside wall, and vent it through wall. You'll be spending in the middle range if your stove is on an interior wall, or if there's a brick or stone exterior on your house. Expect to pay the most when venting through roof, especially if the stove is on first floor of two story house, or if you've got a tile or metal roof.

In this customer’s particular case, venting the stove up through the roof is not an option. Her stove is on an interior wall that backs up to the living room. So, what’s the solution?

If you can’t go up, just look down, Mike says.

“You can easily run the venting pipes down through the kitchen floor into the basement, then across the basement ceiling to an exterior wall where you can install a vent,” he says.

Let’s get started
First, here’s list of what you’ll need:

• An duct elbow joint

• Round duct piping that is 5” in diameter (that tends to be the standard) and long enough to reach from the oven, through the floor to the basement;

• A length of 5”-diameter flexible aluminum duct piping that is long enough to reach across the basement ceiling from the exterior wall to the area below your stove;

• Two metal adjustable hose clamps for clamping the adjustable piping to the vent and other duct work.

• You’ll also want to have a keyhole saw on hand because you’ll be cutting circular holes in the kitchen floor and the exterior wall of your house.

• An exterior vent that you’ll mount on the outside of your house and connect the flexible piping. There are three basic types shown here in Figures 1, 2 and 3. Mike’s vent of choice is the one pictured in Figure 1. “These are easy to install, will keep the critters outdoors and they are easy to paint to match the exterior of your house,” he says.

From the outside in
It might seem natural to get the saw out and start cutting a hole in the floor, but Mike says, “Whoa! Let’s start from the other end.”

He recommends figuring out where you want to put the vent on the exterior wall in your basement and then cut a 5-inch hole in the wall. “You want to try and make the hole fit the vent as tightly as possible so that any exhaust doesn’t escape back into the house he says.”

Once you’ve cut the hole in the wall, firmly affix the vent to the outside of the house using screws that will hold through wood and/or aluminum siding. Then go down to your basement and fit the flexible piping to the vent using one of the adjustable rings.

Now it’s time to start cutting the hole in the kitchen floor. Before you cut, it’s really important to make sure the spot you’ve chosen to run the piping lays in between the floor joists. The last thing you want to be doing is cutting through one of those your you’ll jeopardize the stability and support of your flooring in the kitchen.

To help guide you, put one end of the straight duct piping up to the ceiling and trace a circle around it.

When you go to cut a hole in the floor to accommodate the pipe, you want to make the hole about 7-8” in diameter. This provides the piping some room to give in case you need to move the stove a little bit here or there. Mike recommends using the straight aluminum duct piping here because the flexible type is easily perforated and you could end up with an air leak.

Once your hole is cut, attach the straight duct piping to the stove and feed the piping through the hole in the floor.

Now head back to the basement and attach the elbow joint to the duct piping coming through the floor. Lastly, use the other hose clamp to fit the flexible piping to the elbow joint.

That’s it – you’re cooking now!