Duct for kitchen exhaust hood?

[nc747]

Early on my wife and I decided on a "ductless" range hood over the stove in our home under construction. Although this isn't very appealing because no moisture or odor would actually be removed from the kitchen, the decision was made based on the builder's assessment that exhaust duct would consume the entire cabinet over the stove, and the fact that another cabinet was being lost to an air return at the time.

Now after investigating myself, I find that the required duct is only 3.25" x 10"!! However, sheetrock and cabinets are in place. It seems running the duct horizontally through the wall and into the garage might still be a possibility at this point; then the duct could be converted as needed and run to the right to an outside wall within the garage. Straight up is into the second floor bath .

The only problem is a stud that is approximately in the center of the range hood space that has wires running down it. Most range hoods I've seen have the exhaust duct in the center, so the duct would intersect and sever the stud/wires if run straight through. Is it possible to split the duct around the stud/wires? What's the conventional way of handling this, even without the presence of wires?

These (fairly large) pictures show the cabinet wall before and after sheetrock:

http://home.triad.rr.com/dmhome/RangeHood/

Thanks!

[1manband]

Make your builder pay for the "add". He was doing nothing more than jerking your chain. He just didn't want to deal with the duct to begin with. The stud in question could have been moved to accomodate your venting. The ventless range hood is for trac homes, right or wrong, yours is not. You WILL have problems forever if you don't vent the range.

[johnsp]

If you don't mind loosing a litte cabinet space, vent the hood up and transition to a 4" round duct. Get flex aluminum 4" dryer vent hose and offset a few inches left or right to go out the back wall into the garage. As said, you don't want to pass up on a stove exhuast. Saves on cleaning and grease and grime off the walls and cabinets. You'll repaint the kitchen ceiling less often.
If the garage walls are still open, you should be able to add studs and cut the one in question. Wires should have enough slack to fit around a duct or be extended worst case.

[tinner73]

john.......i think he needs 6" round or wall stack.

[nc747]

I forgot to mention that the plan is to also have the microwave above the stove. So a horizontal duct is really needed. Is there any way to "split" the duct around the stud, or some other workaround?

Our kitchen is 12'x13' open to an adjacent 8'x13' breakfast nook. We will have a 30" electric stove. On the garage side of the wall, it is 3-4' to the right to the outside wall. There will be a need for 1 or 2 elbows, depending on the height that the duct comes out at.

How many CFM are needed? Any suggestions for a model that will mount below microwave (assuming there is a way to work around the stud)?

Thanks

[dallasbill]

Why did someone delete my earlier post?!

You never use flex aluminum dryer vent hose for an exhaust vet stack. It collects grease etc. and the CFM is greatly reduced. Every vent manufacturer says this!

So, why was my post stating this earlier today deleted in this forum?? The OP needs to know this.

[tinner73]

check hood for cfm.

[marauderx]

Originally posted by dallasbill
Why did someone delete my earlier post?!

So, why was my post stating this earlier today deleted in this forum?? The OP needs to know this.

The server went down for a bit, wiped out a bunch of posts that weren't saved.

[m kilgore]

Microwaves are usually 300 CFM with a 3.25 x 10 opening for venting. This can usually be taken out the top or back with moving the fan on unit. There would not be enough room to slpit the duct but we have added many and its shouldn't be to much work to move the electrical and header off the stud from the garage side. Then you could transision to round in garage and go out. With codes in our area the garage if a 1 hr rated fire wall so all venting would need to be framed in and drywalled for 1 hour. As stated earlier the builder should need to take a hit for some of this as he wasn't very helpful in the beginning but you should be ready to pay the standard upgrade for this job. Also as stated this needs to be run in a minimum of 6" pipe with no skrews and NO flex pipe. Also if in the garage it should be insulated so it dosn't sweat in extreme weather.
Good luck