{"id":6135,"date":"2022-08-28T11:12:28","date_gmt":"2022-08-28T15:12:28","guid":{"rendered":"https:\/\/rangehoodhomeland.com\/?p=6135"},"modified":"2023-04-24T21:35:11","modified_gmt":"2023-04-25T01:35:11","slug":"what-is-makeup-air","status":"publish","type":"post","link":"https:\/\/rangehoodhomeland.com\/culture-and-community\/what-is-makeup-air\/","title":{"rendered":"What Is Make-up Air? And When Is Make-Up Air Required? (Answered)"},"content":{"rendered":"\n

If you\u2019re looking for a new range hood<\/a>, you\u2019ve also heard of the term \u201cmake-up air.\u201d But what exactly is make-up air, and when is make-up air required?<\/strong><\/p>\n\n\n\n

In this article, you will learn what a make-up unit kit is, why it\u2019s important, and how to determine if having one is required for your kitchen.<\/p>\n\n\n\n

A make-up air unit \u201cmakes up\u201d the air exhausted from your home via your range hood<\/a>. A make-up air unit is required if your range hood exceeds 400 CFM.<\/strong> But even if it\u2019s not over 400 CFM, a make-up air unit is highly recommended because negative air pressure will hinder your range hood\u2019s performance without it.<\/p>\n\n\n\n

What is make-up air?<\/h2>\n\n\n\n

Make-up air, as its name indicates, \u201cmakes up\u201d the air exhausted by your range hood<\/strong>. When you operate your range hood, it removes filthy air from the kitchen<\/a>. Clean air must be reintroduced to the area once the dirty air has been removed. So it essentially brings fresh air in from the outside.<\/p>\n\n\n\n

What is a make-up air kit?<\/h2>\n\n\n\n

A makeup air kit, also known as a makeup air unit or makeup air system, consists of a range hood damper and an air pressure sensor that regulates outside airflow into your home. It connects to your ductwork<\/a>, and a pressure switch signals the damper<\/a> to open, allowing fresh air into your home.<\/strong><\/p>\n\n\n\n

A make-up air kit will improve your home’s ventilation and indoor air quality<\/a>. If you’re doing a lot of high-heat cooking, it can also be used to cool down a room<\/a>.<\/p>\n\n\n\n\n\n

Why is make-up air important?<\/h2>\n\n\n\n

Without a make-up air unit for your kitchen, your exhaust hood won\u2019t accomplish its job as effectively.<\/strong> That\u2019s because the absence of supply air creates a rise in static pressure that decreases the cubic feet per minute (CFM)<\/a> of air the equipment can remove from your kitchen.<\/p>\n\n\n\n

Thus your hood won’t work properly. When your exhaust hood doesn\u2019t operate correctly, you\u2019ll notice more grease piling up on your kitchen surfaces<\/a>, and you\u2019ll have to spend more time cleaning. And respiratory difficulties might arise as a result of prolonged exposure to smoke and toxins. And when your kitchen lacks replacement air, your heating and cooling conditions will be uneven.<\/p>\n\n\n\n

When is make-up air required?<\/h2>\n\n\n\n

Make-up air units may be required<\/strong> in the following situations:<\/p>\n\n\n\n

  1. You have a very small kitchen with little space.<\/li>
  2. Your kitchen has poor ventilation<\/a>.<\/li>
  3. Your kitchen requires it per the building code.<\/li>
  4. You use your range hood often.<\/li><\/ol>\n\n\n\n

    1. Small Kitchens<\/h3>\n\n\n\n

    You may notice difficulties with negative air pressure<\/a> if you operate your range hood in a compact area or if you don\u2019t have a well-performing range hood.<\/p>\n\n\n\n

    Negative air pressure means the pressure within your house is lower than the outside air. This pressure differential might allow outside air to leak into your house. <\/p>\n\n\n\n

    Your range hood or exhaust fan must have positive air pressure to function effectively. If your pressure is negative, the range hood will have a tough time extracting air and performing at its best.<\/p>\n\n\n\n

    You may have negative air pressure if you see inward-facing doors opening rapidly or if your doors are difficult to open<\/strong>. Whistling or crackling noises may also be heard. Keep an eye out for growing energy expenditures, a strained HAV system and drafts.<\/p>\n\n\n\n

    2. Poor ventilation<\/h3>\n\n\n\n

    Your kitchen range hood will not perform at its best if you have poor ventilation. Make-up air units are recommended for households that need additional ventilation. Using a range hood or exhaust fan, you should constantly circulate clean air back into your house.<\/p>\n\n\n\n

    If you don\u2019t have a make-up unit and have a ventilation problem, air<\/strong> will be drawn from other sources, such as your HVAC system<\/a>, water heater, or chimney<\/strong>.<\/p>\n\n\n\n

    3. Building code regulations<\/h3>\n\n\n\n

    The building industry in the United States has long recognized the need for enough make-up air for exhaust systems. Since 2009, the International Residential Code (IRC) has mandated the provision of make-up air for kitchen hood exhaust systems with a capacity of 400 CFM<\/a> or larger. However, you should still check your local codes if this information is outdated or has changed since it was published.<\/p>\n\n\n\n

    4. Long-term use of a range hood<\/h3>\n\n\n\n

    If you wish to leave your range hood on for hours at a time<\/a>, you\u2019ll almost certainly require a make-up air unit, regardless of its CFM. The longer your range hood runs, the more air is expelled from your kitchen.<\/p>\n\n\n\n

    If you want to further understand how make-up air works and when you might need it, watch this video called \u201cAll About Make-up Air\u201d<\/em> from the This Old House YouTube Channel.<\/p>\n\n\n\n

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