Where would you vent the kitchen exhaust? Wall or roof?

fidelfs

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I am buiding my kitchen cabinets and I have a vent hood liner that I need to install to exhaust the odor, fumes, and heat to the exterior.

I have a one story house, the other side of kitchen wall is the side beteween my neighboor and my house.  There are approx. 13 feet between their house and mine.

If I vent thru the wall, I will have to cut a stud and rebuild it, my exterior wall is brick fascade.  If I vent thru the roof, the vent hood will be very close to the bottom of the roof.

Where would you vent it? And why?   ???
 
I would vent through the roof as its the easiest depending on your tiles!  You can get tile vents and job done!

If you was to go through the wall why would you have to rebuild your studding?   Wouldnt you do a pilot hole through to out side then core drill from out side in and then use a fein or something to cut I nice tight hole in the studding if it lands on a stud if your are lucky you might miss and come between a 400 centre studding.   If it has plywood ontop then use a hole cutter to cut.  I dont see any need to repbuild.   Either way can be simple as long as their are no pipes or cables but the roof is the quickest and easiest.  you can use flexi ducting so you can easily go higher up so your not to close the the eave tiles at the bottom.

JMB
 
You can vent through the roof, but use an offset duct to put it further up the roof line.  Also make sure to check the appliances your venting for their exhause cfm requirement/vent size and shape (round or rectangular).

Your neighbors will appreciate not smelling what's venting from your house.
 
You mentioned the other building being 13feet away I assuming your worried thats to close?    ITs only a normal kitchen extractor your fitting it wont be throwing out a lot of heat and crap its just to take the fumes (if you have a gas hop) and smell really. So I wouldnt worry about stuff like that.   I wouldnt go to much into it to be honest with all this CMF.  Unless your getting a industrial extractor.    They are all pretty much standard and a 4 inch ducting does the job well here in the UK any way.      

Alot of people here on budget kitchens have filtters fitted ones so they dont vent outside at all so if they are good enough having ducting is a luxury!

JMB
 
Just some types of Tile Vents

http://www.sandpipersupplies.co.uk/shop/browse/Vent_Tiles/?p=-2

Thats how it normaly connects!  you fit the tile vent on the roof cut a small as possible hole through the felt and folding it up to if water went to the felt it wood run around.   you then go into the loft and connect the adapter which is flexible to your flexible ducting.
http://www.manthorpe.co.uk/SiteData/Root/file/BuildingProducts/RoofVentilation/Tile%20Vent/MBP8297a%20-%20GTV%20Tile%20Vent%20Range%20-%20Mechanical%20Extraction%20Information%20Sheet.pdf

JMB
 
jmbfestool said:
If you was to go through the wall why would you have to rebuild your studding?  

JMB

Hi,
Yes, I am worry that 13 feet is not enough.

I meant I will have to make a header to redirect the load to the 2 other adjacent studs. Something like this

Cutting the stud

The exhaust will go thru the mid stud and I will have to cut it, the exterior wall is a load bearing wall.  So I have to make a header something like this to transfer the load to the other 2 studs.

Making the header  
 
The drawings are for a door installation, but this will give you the idea what I am going to do.

The idea is I will remove the mid stud to accommodate the pipe 6" for the instructions. The vent hood liner is 900 cmf, it is rated for standard 30 inches stove.  It is not professional but it is better than others.

Why I need to vent outside?  Well, I am hispanic and we eat a lot of fry food, and all the heat and grease is released inside of the house, I tried before the filter but they were not enough for the type of food we cooked.  
We have a natural gas stove with 4 burners.

This is the type of liner I have, I made the outside using plywood, the shape is very similar to the picture.

 
What does code require?  May not matter now, but when it's time to sell the place...
 
fidelfs said:
jmbfestool said:
If you was to go through the wall why would you have to rebuild your studding?  

JMB

Hi,
Yes, I am worry that 13 feet is not enough.

I meant I will have to make a header to redirect the load to the 2 other adjacent studs. Something like this

Cutting the stud

The exhaust will go thru the mid stud and I will have to cut it, the exterior wall is a load bearing wall.  So I have to make a header something like this to transfer the load to the other 2 studs.

Making the header  
 
The drawings are for a door installation, but this will give you the idea what I am going to do.

The idea is I will remove the mid stud to accommodate the pipe 6" for the instructions. The vent hood liner is 900 cmf, it is rated for standard 30 inches stove.  It is not professional but it is better than others.

Why I need to vent outside?  Well, I am hispanic and we eat a lot of fry food, and all the heat and grease is released inside of the house, I tried before the filter but they were not enough for the type of food we cooked.  
We have a natural gas stove with 4 burners.

This is the type of liner I have, I made the outside using plywood, the shape is very similar to the picture.

I see! Well go through the roof then lol. You don't want to be trimming the studding out a lot of work aint it.

Jmb
 
b_m_hart said:
What does code require?  May not matter now, but when it's time to sell the place...

That is a good point,  I will find out. There are several houses exhausting on the wall, that was made by the builder.

 
Although it won't solve the proximity problem a simpler solution might be to take it up into the attic then vent to the gable end or soffit depending on the situation. This would eliminate the need to cut the wall stud and also the problems of waterproofing the roof penetration. In Alberta this is a approved install.

Gerry
 
The thing that hasn't been mentioned yet is the efficiency of venting through the wall.  You'll likely have less than a foot of straight pipe though the wall, through roof the airflow will need at least one 90 degree turn and probably six feet or more of pipe.  The longer run and turn will reduce the efficiency of the venting.   
 
No significant loss in efficiency as long as the design is correct and follows the appliance manufacturer's instructions.  Out the back of the appliance to go thru the wall usually involves a 90 within the appliance and therefore you get your 90 one way or the other.  I still say everything will be fine sticking with the venting instructions.  Manufacturers go through a lot of testing to get that right for safety reasons, U.L. reasons and protection from legal recourse.
 
The instruction should tell you the max on how many feet the duct can be.
Just to give you an idea,my microwave/vent hood has a max of 40',not including elbows.
I would do thru the roof.Easier!
 
I think the most important aspect of this thread is whether or not through OP would care to share a recipe for carne asada.  I miss good Mexican food.  [big grin]

Jon
 
I had to look into this while building out house and was surprised to find that you aren't required to vent outside at all. So rather
than make ANOTHER vent hole in my super efficient straw bale house, I chose for a filtered recirculating fan that dumps back into
the kitchen (great room really). That way any heat form the stove gets put back into the house, thus helping our passive solar design even more.

Here's the results (with a bit of fancy metal work, some carefully stained 2x's, and about 9 months of custom coloring "behind the barn")

 
man that is a big exractor fan. you could live in that.

these openings really kill energy efficiency. a normal sized fan could ruin months of work air sealing and insulating a passive house.
way to go fritter63. straw bail it sounds stupid but is great for the efficiency numbers. great thermal mass and sound deadening
 
Like Alan said!      What about when they make you have a air vents 4 your living room if your fire place kicks out more the 10kilo wats or something like that.  I never put air vents in I refuse to do it it's redicilous  like you said you spend so much money on insulation then you are made to drill a 4inch hole in your living room to allow air to pass through  ridiculous!  So many people work with building regs and building inspectors but every job I work on always seems to get away with it don't understand the fuss. Only these really big jobs have to abide with building code.

My parents  used to have a massive fire burner and they had no vents and it worked so well that it made the room so hot you couldn't actually stay in the room. It's a load of crap these vents they make you have for fire burners.

So if I was fitting a extractor fan I would just drill a 4inch hole through the wall or vent through the roof don't make a big deal out off it its all a load of crap.  Not need to worry about this and that if extractors passes on fillters then like I said a vent outside is a bonus.  Forget all these building codes just use commen sence man.

Soon der will be regs on how you screw a screw into wood.

Jmb
 
Alan m said:
these openings really kill energy efficiency. a normal sized fan could ruin months of work air sealing and insulating a passive house.

A flapper door(s) seals the opening when not in use.  You're making it sound like a window staying open all the time.

As for JMB and his comment, all I can say is you've still got a lot to learn (probably the hard way), and I'm sure my words will have no effect on you.  Maybe in 20 years I'll be able to say, "I told you so."  Maybe I should say this to JMB, with a fireplace, there needs to be oxygen and if there isn't enough "make up air" from the room, you need a fresh supply of air so the oxygen isn't depleted from the room.  Living quarters : room : fire place : people :oxygen .... get it?  The problem isn't just carbon monoxide produced during combustion.  It's also about having a continuous correct balance of oxygen, carbon dioxide and nitrogen in the immediate surrounding area for people to breathe and survive.
 
ken
even with a flap door on the pipe there is no u value to the traped air. the trap door is there to stop the wind blowing in. the pipe still acts as a thermal funnel sucking out the heat. these are worse than an open window in that you cant properly close them
i was specifically talking about passive design. the very smallest gap in the the building envelobe.the same applies to normal buildings. you cant ever see most of the gaps that engineers are chasing when they do an airtightness test on a passive home.

as for the jmb comments. i would never install a fireplace in a home without a vent. ken is right in what he is saying but in the uk most houses have a special vent that allows outside air to be pulled in under the fire box and up the chimney. this is a pipe under the floor . this is a more energy effiecient system than the 4 inch hole in the wall.

in my country they removed the requirment fot the hole in the wall vent as they are way to over used. people had them in every room. one 4inch vent is enough ventillation to supply a 4 bedroom house with 5 ocupents. now we use small vents in the pvc windows (1/4inch by 6inch slots).
do the math and you will see
 
Alan m said:
as for the jmb comments. i would never install a fireplace in a home without a vent. ken is right in what he is saying but in the uk most houses have a special vent that allows outside air to be pulled in under the fire box and up the chimney. this is a pipe under the floor . this is a more energy effiecient system than the 4 inch hole in the wall.

We have a BIS wood burning stove for backup heat - 70,000 BTUs when that puppy is going strong. It's totally enclosed (glass doors) and draws it's own combustion air through a 6" vent pipe from the outdoors. The heat from the fire gets transferred to the house as a natural convection current forms around the firebox (intake on the bottom, outtake on the top).

So, no outside air is ever used inside the house, only inside the firebox.

But we're way off topic now....
 
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