In the US, the construction industry has long recognized the need for adequate makeup air for exhaust systems. Beginning in 2009 and in every version since, the International Residential Code (IRC) has required that makeup air be provided for kitchen hood exhaust systems with capacity of 400 cfm or greater.

Do I really need make up air?

In the US, the construction industry has long recognized the need for adequate makeup air for exhaust systems. Beginning in 2009 and in every version since, the International Residential Code (IRC) has required that makeup air be provided for kitchen hood exhaust systems with capacity of 400 cfm or greater.

Why do I need makeup air for my range hood?

In homes with naturally drafted fuel-fired appliances like a boiler inside the envelope, kitchen range hoods that exhaust more than 400 cu. ft. of air per minute require makeup air so they don’t depressurize the home and draw combustion gases from the appliance into the living space.