I have a potential client who just bought a house. The inspector neglected to point out in the kitchen that there was no vent duct for the range hood. The sellers had a hood that recirculated but had a surround that looked like there should be ducting. Above this is a bedroom and installing something in the wall would be a pain and expensive. Someone mentioned to the buyer that a hood could be installed, the duct run down the wall and under the house with an in-line fan to push the air. I’m shaking my head thinking this is a disaster waiting to happen with possible grease build up in an elbow. It would be about a 7′ drop and then a 20′ run to outside. The buyer does not want to use the recirculating idea as she cooks a lot and thinks the air will not be properly filtered. She also does not want to invest in a Jenn-Aire type downdraft model. (BTW, how does Jenn-Aire deal with venting down and not have the same problem?)
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criddle,
A pain and expensive (not sure of the cost as I know not where this pipe has to go...)
not keen on going down 7', then 20 to the exterior exit.........
Indeed a dilema.
Speak more on the going up (and I assumer over-to exit a wall, or up into the attic space and out the roof) Detail the const. of these routes?
The main issue is the kitchen wall is an inside wall that doesn't seem to line up with the upstairs outside wall. If it did, it is a vaulted ceiling then out to the roof. There isn't any access to the space between floors, so up comes the carpet. So between the 15' or so run up, the carpeting and then the patch job on the sheetrock is where I am waffling. I know anything is possible, but how to keep the cost down and also be ready for holiday parties for them...
alright,
Then perhaps a remote fan (none in the hood) could be spec'd that would be strong enough for the downward route.
A good hood with excellent grease filtering that is accessible should keep the pipe clean. Now all you need to do is move enough air to pull, then expel the exhaust. A remote fan would also be queter. Figure the cfm drop from all the down over and out and find a fan from ventahood or fantech that would do the job.. Though I have never seen a downdraft except in the Jennair type of application-I would think it possible to do it with an over the range hood.
I'd contact ventahood, fantech and perhaps panasonic (if they do range exhausts), or broan/nutone.
Don't fergit the make up air if you deem it necessary (as many recommend).
venting dilemma
could you build a box above the cabinet and vent to the outside wall? I guess it would take about 10/12 feet
Even if you go perpenticular across the kitchen with the box, install recessed lighting and make a feature out of it
I looked at possibly going up and over, but the inside wall is where the range is. Two negatives are it is still about an 18' run and I'd have to build a soffit that cuts through a dining room and across a fireplace. I didn't see any way to do it cleanly.
exhaust vent
does the kitchen not have an outside wall?
Vent to to there, even a dropped ceiling will be more economical than messing with elbows and long runs, aux fans etc.