Best range hood duct options?
My house currently has a recirculating range hood which is basically worthless. As part of a minor kitchen overhaul (countertops, backsplash, appliances), I am considering upgrading to a functional range hood.
From a building science viewpoint, are there any particular reasons to choose ducting through the wall vs ducting through the roof?
Could I instead duct through the ceiling and then make a turn to a grille in the soffit area instead of going through the roof?
The range is on an outside wall with exterior brick. Cutting a hole in the brick doesn’t bother me. Not yet sure if I will have any studs in the way.
The roof is a hip roof along that wall so space in the attic is tight near the wall but it wouldn’t be too difficult.
Upper cabinets are open above so I’d have to find a way to hide any duct that goes through the ceiling.
The new range will be electric and most likely will have an induction cooktop.
Venting into the soffit area is intriguing because it would eliminate the need for holes in the brick wall or roof.
I’m in Lubbock Texas which is basically on the border between Zones 3B and 4B. We can easily have 3B summers and 4B winters as the extremes.
Appreciate the help.
DC
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The output of the range (fuel type, number of burners) , intended route of the exhaust pipe and the capture area (size) of the hood dictate the power requirements of the exhaust fan.
IMO the most ideal set up is the one you have. Induction range on an exterior wall. You can vent it right out the back of the wall. The second ideal set up would be straight up through the roof. With an induction range you won't need a high powered (600 cfm+) exhaust fan so you will most likely not need to worry about make up air ducts, or the back drafting of any gas powered water heaters.
Just make sure:
No 1: The range is at least 6" (3" over hang on each side) wider than the range and mounted low enough.
No 2: Use the right-sized diameter of vent pipe
No 3: The vent pipe is smooth metal duct, NOT flex.
No 4: Limit 90 degree bends.
I would not vent into the soffit because you'll introduce water vapor, smoke, grease into your vented attic space.
Thanks John,
I can't implement suggestion #1. I'm constrained to a 30" under mount range hood due to the cabinet configuration.
I agree that I shouldn't have to worry about make up air or back drafting. The gas water heater and furnace are in a closet outside the building envelope and the fireplace is a direct vent gas. The house is not likely built tight enough to warrant a make up air source although I am air sealing as best I can as I continue remodeling room by room.
I did not mean to suggest dumping the exhausted air into the soffit. I meant to run the duct to the outside via a soffit mounted grille. I do not have a continuous soffit vent. The exhaust grille would take the place of one soffit intake vent and would then be 60" from each of the two soffit vents on either side.
Even though it means cutting through a brick wall, I like the idea of venting directly out of the back of the range hood. However, I did some investigation yesterday and learned that I do have a stud in the way of a rear exhaust. The left edge of the stud is 17" from the left cabinet.
Does anyone know of a range hood that has an offset rear exhaust so that I can avoid dealing with the stud?
DC
I just installed a through the wall unit but I haven't yet installed the exterior damper and duct adapter. There's really no way to properly seal the duct inside the wall. I'm just planning for a nominal friction fit. I believe a ducted system through the soffit would be a cleaner way to go.
Thanks for the input, Joel. I am a bit concerned about getting the duct through the wall and properly sealed and installed.
In addition to the stud that is in the way, I know the 240V wire to the range is in the same stud bay as is the 120V wire for the existing hood. Hopefully, if those wires are attached to that stud, there will be enough slack to relocate away from the duct.
I found one range hood yesterday that has an offset top exhaust but so far I'm striking out on finding one that has an offset rear exhaust.
DC