# Residential Kitchen Makeup Air



## righter101 (Apr 12, 2013)

From 2009 IRC M1503.4 Makeup air required. Exhaust hood systems capable of exhausting in excess of 400 cubic feet per minute (0.19 m3/s) shall be provided with makeup air at a rate approximately equal to the exhaust air rate. Such makeup air systems shall be equipped with a means of closure and shall be automatically controlled to start and operate simultaneously with the exhaust system.

Anyone have ideas on how to apply this to a hood or downdraft to get the automatic control without violating the UL listing by adding wiring or a relay??

How are folks treating this in other jurisdictions?

Thanks.


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## steveray (Apr 12, 2013)

I make them supply a work contract (at permit application)to have a guy come over and open a window while they cook!.....Just my way of helping the economy!...Sorry, it's Friday and I don't feel well!......We are in soooooo much trouble when we finally go 2009 IRC later this year.....

All kidding aside....Anyone wanna add what the "average" range hood/ microwave exhaust rate is? I might need to know come October or so!


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## righter101 (Apr 12, 2013)

steveray said:
			
		

> I make them supply a work contract (at permit application)to have a guy come over and open a window while they cook!.....Just my way of helping the economy!...Sorry, it's Friday and I don't feel well!......We are in soooooo much trouble when we finally go 2009 IRC later this year.....All kidding aside....Anyone wanna add what the "average" range hood/ microwave exhaust rate is? I might need to know come October or so!


Does the contract specify how far open the window needs to be??

I built my new place under 2006 IRC and have a 800 cfm fantech inline exhaust for the kitchen.  Love the thing.  I see kitchen exhaust in the 100 to 1000 cfm range.


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## klarenbeek (Apr 12, 2013)

For a hood only (not microwave) you could use a current sensing relay on the power to the hood.  You could also use a sail switch in the duct for the exhaust.

As far as cfm, most of the average microwave/hood combos are around 300 cfm.  We've been on the 2009 codes almost 3 years now and had a lot of issues at first, but most went away after a while.  A lot of contractors figured it out quick and went with hoods of 400cfm or less.  The most common non-microwave one I see is rated at 390.

I'm still trying to figure out why anyone would need 1000 cfm on a residential hood. A typical listed type I commercial hood requires 150cfm per foot of hood, meaning 1000cfm would take care of a 6' commercial grease hood!


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## Yikes (Oct 18, 2013)

klarenbeek said:
			
		

> I'm still trying to figure out why anyone would need 1000 cfm on a residential hood. A typical listed type I commercial hood requires 150cfm per foot of hood, meaning 1000cfm would take care of a 6' commercial grease hood!


Very late to this conversation:  My area of Southern California has seen a large influx of buyers who cook ethnic foods, particularly certain types of asian foods (kimchi soup) and wok cooking that make for some really stinky or spicy air in the kitchen.  A big market has sprung up for high CFM exhaust fans.  A lot of newer luxury homes are even being designed with an additional room/closet in the kitchen just for wok cooking, that can be closed off from the rest of the kitchen to isolate the odors.


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## Coder (Apr 16, 2015)

Old thread but thought I might get an answer here. Are there any provisions for tempered make up air in residential kitchens? There is for commercial kitchens. With the way some of these "high end" residential kitchens are these days they are leaning towards being commercial anyways. Seems there should be some language in the IMC that requires tempered make up air when it is the dead of winter cold outside.


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## mjesse (Apr 16, 2015)

Coder said:
			
		

> Are there any provisions for tempered make up air in residential kitchens?


Not yet.

Seal the house up tighter than a drum to meet energy codes, then punch holes in it everywhere to provide make-up air. Dumb


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## retire09 (Apr 16, 2015)

Makup air does not have to be by mechanical means. A vent opening to the exterior with a back draft damper will respond automatically to the exhaust and meet the requirement.


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## Coder (Apr 17, 2015)

mjesse said:
			
		

> Not yet.Seal the house up tighter than a drum to meet energy codes, then punch holes in it everywhere to provide make-up air. Dumb


Exactly!  Precisely why I have decided I am going to create my own code section to address cold makeup air and add it to the City code next go around on adoption of the 2015 I-Codes


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## mjesse (Apr 17, 2015)

A 300 cfm HRV is only about $2,000 plus labor.


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## tmurray (Apr 17, 2015)

mjesse said:
			
		

> A 300 cfm HRV is only about $2,000 plus labor.


That's a lot of air for a dwelling unit.


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## mjesse (Apr 17, 2015)

tmurray said:
			
		

> That's a lot of air for a dwelling unit.


Until they switch on their 600 cfm kitchen exhaust hood.


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## Francis Vineyard (Apr 18, 2015)

Coder said:
			
		

> Exactly!  Precisely why I have decided I am going to create my own code section to address cold makeup air and add it to the City code next go around on adoption of the 2015 I-Codes


  Virginia amendment;

Exception: Intentional openings for makeup air are not required for kitchen exhaust systems capable of exhausting not greater than 600 cubic feet per minute (0.28 m3/s) provided that one of the following conditions is met:

1.	Where the floor area within the air barrier of a dwelling unit is at least 1,500 square feet (139.35 m2), and where natural draft or mechanical draft space-heating or water-heating appliances are not located within the air barrier.

2.	Where the floor area within the air barrier of a dwelling unit is at least 3,000 square feet (278.71 m2), and where natural draft space-heating or water-heating appliances are not located within the air barrier.


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