Need Help w/ Kitchen Addition Venting Range Hood

[Deleted User]

I need some help / advice with my kitchen addition. I am installing a range hood and would like to vent it to the outside. It needs to extend up the back wall 2 to 4 feet and across the ceiling about 10 to 11 feet to the outside. I am pretty sure its okay to do this as long as the fan is powerful enough. I am trying to minimize bends in the pipe and use 45 degree turns if possible. Any pointers to offer ? What size pipe do I need to use ? Suggestions welcome. Thanks. :cool:

tonyb

I would imagine you'd have to check your local codes. Obviously you can't have a rinky dink hood over a 8 burner Wolf stove. As far as that length to get to the outside, I see condensation as a possible problem and grease build up. Cant go straight up ?

WagnerRC

mount a fan close to the exit for better extraction

dkg999

That's a long run with moisture laden air cooling on the way to the exit. I don't remember what code says and don't have any of my reference books available at the moment. Can you downdraft to the basement and a more accessible duct run? Can you go up through the roof and a shorter run? +1 on having the fan unit closer to the exit.

cristo

+1 on avoiding rinky dink hoods, like the kind you usually see at lowes, home depot, etc.
We got a Five Star rangetop (4 burners with a central griddle) and the Five Star hood that
matched to it flows great, if a little noisy, even with about 10 feet of pipe to the exit..

SCompRacer

Maybe consider a critter guard over the exterior vent. Like this.



Shortly after we moved in our house, we had a Grackle that hung off the siding and opened the flap door and crawled in the vent pipe looking for a new home. After evicting it I installed a guard.

Joe08867

critter guards are a real good idea.

mrbiron

Check the unit cut sheet on this. It will tell you the maximum run and will step it back with every 90 degree bend that you put in the run.
The top will most likely have a knock-out for a rectangular and/or ~6" duct or at least that is roughly the size for the 200+ that we just put in the project my company is doing. Your run i relatively short and you won't have a problem with properly venting this. Our max run is in the 30' range so do not fret about that. Again, your unit cut sheet will cover this.

[Deleted User]

mrbiron wrote: »

Check the unit cut sheet on this. It will tell you the maximum run and will step it back with every 90 degree bend that you put in the run.
The top will most likely have a knock-out for a rectangular and/or ~6" duct or at least that is roughly the size for the 200+ that we just put in the project my company is doing. Your run i relatively short and you won't have a problem with properly venting this. Our max run is in the 30' range so do not fret about that. Again, your unit cut sheet will cover this.

Sounds like you do a lot of this sort of thing. Any recommendation on brands to use or to avoid ? :cool:

michael1947

Can you go down...into the basement or crawl space. This would eliminate unsightly business in the kitchen or at least cut cost way down as you could use inexpensive pipe. Also, can you skin the outer surface, drywall, plaster, wood from the wall behind the stove and go up within the wall with shallow rectangular pipe like a 3 x 12.

mrbiron

Sounds like you do a lot of this sort of thing. Any recommendation on brands to use or to avoid ?

I work for a large scale residential development (apartment complexes) general contractor and we have corporate accounts with GE and Whirlpool buying appliances by the thousands for our clients per year. When it comes to hood vents, there really isn't much to worry about as the failure rate is in the ballpark of 1 in 50 that has a shot motor/loud fan. It's the other, more complicated appliances that you need to shop around for.

Happy Shopping :cheesygrin:

[Deleted User]

michael1947 wrote: »

Can you go down...into the basement or crawl space.

That part of the house is over a crawlspace and I would prefer not to go down. I will be installing a freestanding range and I don't think you can downvent those. One of the options I have stumbled across is by a company called Vent-A-Hood and it looks like they have some interesting innovations for vent / no vent as well as some proprietary technologies. I will be seriously checking into them. Cheers. :cool:

drselect

nap wrote: »

One of the options I have stumbled across is by a company called Vent-A-Hood and it looks like they have some interesting innovations for vent / no vent as well as some proprietary technologies. I will be seriously checking into them. Cheers. :cool:

nap, we have a Vent-A-hood. I think I have posted picture of it some place on here before. It is well constructed and have never had any problems with it. Its a beast thought. Had to have a special 12" duct and roof vent made for it. Helps to have a big utility sink to clean the fans on it. Last summer I just took them outside and cleaned them with a powerwasher.

muncybob

Good timing on this thread as the Mrs wants me to install one. The Vent-A-Hoods look real nice, hope we can find a dealer that we can go look at them.
The exhaust piping for us would exit directly from the rear and have to travel thru an unheated air space of apprx. 10'. I wonder if I'll have condensation issues?

disneyjoe7

Not sure this would help you, but have a down draft vent in my house which is under the concrete slab. Its ran in pvc under floor, I recently seen this pipe and didn't see any condensation problems. The house is 15 yrs old, so thinking if a problem, I would of seen it.

[Deleted User]

muncybob wrote: »

Good timing on this thread as the Mrs wants me to install one. The Vent-A-Hoods look real nice, hope we can find a dealer that we can go look at them.
The exhaust piping for us would exit directly from the rear and have to travel thru an unheated air space of apprx. 10'. I wonder if I'll have condensation issues?

I believe you are okay provided you have enough cfm and the proper size vent pipe. Some of the hoods I have looked at require 8 inch pipe. Also, minimize bends and use 45 degree turns instead of 90. HTH. Cheers. :cool:

muncybob

nap, some of the Broans I've looked at on the net have higher rated cfm and lower sone than the Vent-A-Hoods and I believe a lower cost. Other than some of the accessories you can get with the Vent-A's I'm having a hard time justifying the additional expense. What am I missing here?

jimmydep

As a long time contractor and building inspector in NJ., I have installed and inspected hundreds of exhaust hoods. Before installing any pipe check the manufacture for the minimum size and maximum legnth allowed. I have never seen a hood that used less than a 6" round pipe. The pipe should be 26ga steel and should have a smooth interior with taped joints, and a metal vent hood outside, don't use flex aluminum pipe as it doesn't meet most codes and grease will collect inside. If space doesn't allow for a round pipe you could use a 3.5x10" rectangular pipe. Note that any exhaust piping running through unheated spaces should be insulated with R-8 insulation.

Jimmy