How To Vent a Microwave on an Interior Wall (5 Steps)




Most modern microwaves use recirculatory discharge and don ’ t have to be vented. however, if you have either a microwave above the range or want to keep food smell to a minimal, you might want to vent your microwave .
Venting microwaves on an interior wall normally means installing a ventilation pipe. That might vent to the central ventilation or meet up with the range hood ventilation – depending on your kitchen. In most cases, that’s a simple matter of installing a ventilation pipe and linking it to your existing system.

5 Reasons Why Venting a Microwave is Important 

If you ’ re considering venting your microwave, there are plenty of reasons why it might be necessary. The four below include the most common .

Removing Food Smells 

Recirculating microwaves can result in food spirit buildup. That can cause issues for anyone with sensitivities to smell. evening if you precisely want your kitchen to smell fresh, public discussion can help. Most importantly, if you have a combi-oven, that will matter even more. Recirculating microwave ovens just push blistering air out of the vents into the kitchen, while sucking in raw air. Of course, that ’ s normally pushed through a trickle, but your home will hush smell like anything being microwaved. And in some cases, that ’ s a truly bad thing .

Heat Management 

If you ’ re trying to keep your cooling poster low, venting your microwave outdoors can help a great cover. That ’ second particularly true if it ’ randomness on for longer periods of time. then, again, this is more important if you have a combi oven .

Preventing Moisture Buildup

If you ’ ra installing your recirculating oven inside a cabinet, it ’ mho crucial to add public discussion. differently, the airflow will cause condensation. Why ? Air exiting the microwave is a bunch warmer than publicize outside the microwave, so it will condensate and cause moisture buildup. Vents will ensure your cabinet stays dry .

Installing an Over-the-Range Microwave

Over-the-Range microwaves are antique but silent available in a bunch of shops. If you buy one, it ’ sulfur intended to replace the range hood over your stove. This allows you to save space in your kitchen, by moving the microwave over the stove. The range-hood-microwave features ventilation in the bet on, allowing air to pass through – effectively taking the same character as the crop hood. And, most importantly, it should connect to any ventilating you have in place for the rate hood. If you don ’ t have any, you ’ ll have to install ducts and vent them external .

Local Building Codes

Installing a range hood microwave might fall under local legislation. For exercise, U.S. construct codes require that you vent kitchen exhaust outside. If you ’ re using a roll hood microwave over the stave, it is kitchen exhaust. You might have to install breathing to comply with construction code. That is crucial for guard, because recirculating kitchen consume can result in dangerous fumes. It can besides be crucial for selling the home plate – as you ’ ll have difficulty doing then if your kitchen doesn ’ deoxythymidine monophosphate suffer code .

Things You Will Need to Vent Microwave Through the Wall

If you ’ re venting a microwave, you probably want to either take it through a wall or through to your existing central ventilation. Making the decision should depend on where your central ventilation is or if you have any installed at all. You will need :

  • Measuring tape
  • chalk
  • power drill
  • Phillips # 2 bite
  • Saw / Power saw ( Hacksaw and skill power saw for best effect )
  • flat
  • Stud finder ( optional )
  • Eye protection
  • Tin snips if not using adjustable vent
  • A run


  • Duct pipe that fits your rate hood microwave – This varies well in size so you ’ ll have to check your make and model. E.g., it can be round or rectangular .
  • Elbows and fittings as necessary. E.g., do you have to turn corners with the duct ? Do you want to change it from round to rectangular or square or frailty versa ?
  • Any duct covers as desire
  • Vent collar
  • vent Cap or Hood if you ’ re install in the wall or roof
  • Sheet alloy screws ( normally 1 ”, Phillips # 1 )

Venting Microwave on an Interior Wall: 5 Easy Steps 

If you install a microwave on an interior wall, you ’ ll have to take your duct pipe across the wall or up to the adjacent floor. Your decision to do so should entirely depend on existing ventilation installed in the space .

Check Ventilation Options 

Unless your home is newfangled, chances are, it already has public discussion. This might be existing holes in the wall. It might besides be an existing duct wrinkle for a range hood. Or, you might have a central breathing shriek running up through the sign of the zodiac, to the roof. Check what ventilation options you have and where they are.

If you don ’ t have any, you ’ ll have to cut a newly hole. Doing sol means choosing whether to vent into a wall or into the roof. however, this is largely a personal circumstance – although you might want to ask for a professional opinion in case local build codes show a predilection. In addition, some local codes might not allow you to cut a hole in your own roof. You might need a license contractor to do sol. Venting into walls is less nonindulgent. however, if you are in an urban sphere, you normally have to extend vents out .
Vents extending through a roof must extend at least 12 ” above the roof. vent terminals extending through a wall should not be closer than 10 feet from a set agate line and should be at least 10 feet above the ground horizontal surface. And, in most cases, if you live in cold climates, you want to use gabled release facility, where the vent comes out and then faces downwards, to prevent cold publicize from seeping in through the vent .
once you know where you can run the release, you can decide how to install it. In most cases, that should be :

  • The clean and most lead line, against a wall, to the point of the public discussion
  • The duct should be unobstructed in its path. however, some people prefer to run ducts through cabinets to hide them .
  • A duct can be a maximum of 50 linear feet hanker, with each elbow reckon as approximately 10 linear feet. so, if your central ventilation is besides far away, you may have to vent into a wall anyhow. Or, you may have to install extra fans .

Find the Studs

Use a stud finder, take off the sheetrock, or otherwise find the dot in the wall In most cases, these are 2 ’ apart throughout the entire home. This means that if you find one, you can calculate the rest using a tape measure. For model, you can measure from the corner. however, there ’ s always a chance that your dwelling is not installed to standard, which might mean the studs are off .
Use a pencil or a carpenter ’ s pencil to mark where the stud are. then use the pencil or chalk to trace the line where the duct should install. Measure the duration to ensure it ’ s not besides long. In summation, you want to keep turns to a minimal. so, you ’ re probable running your duct from the center of an home wall, around a corner, to an exterior wall. You might then go up or directly out the wall. Your options here are normally to extend the duct pipe up to the ceiling, to run the duct along the ceiling, and then to make the final turn at the adjacent wall .

Cut Necessary Holes

Mark and cut necessary holes for the duct. In most cases, you want to make holes slightly larger than the duct itself. If you ’ ra installation ducts inside cabinets, you can besides get vent collars to fit inside the holes. These cover the holes and seal the duct against the cabinet, to prevent it from rattling about .
In most cases, the easiest way to cut duct holes is to use a part of the duct to trace a fix. Use a charge to make certain it ’ randomness flat. You want the duration of the duct and the width of the duct to be degree for the fix. Do not cut into rampart stud. Most duct pipe is about 10 ” across, which means you ’ ll have plenty of room to run between the stud .

  • Use a skill see for large, basic holes that will have a cover over them .
  • Use a drill with a spade bit to start a small fix and then use a saber saw if you want accurate holes .

finally, if you ’ re venting directly through the roof or through the wall, you can immediately install the caps to prevent water, birds, or other pests from coming in .

Install Attachments for the Ventilation 

Most vent ducts are installed on hooks or racks. This will entirely depend on which type of ducts you purchased. Install these using a world power exercise, ensuring your screws are drilled into the wall stud. Make certain you follow any specific instructions that come with the ducts you purchased .

Install the Ducts 

Fit the ducts into place, starting with the duct against the microwave. In most cases, you ’ ll have to install the first vent duct and then fit the microwave into set. Why ? Most stove hood microwaves vent to the back and you won ’ metric ton have space to fit a duct in once it ’ sulfur installed. Make sure you have person on hand to help you .
Fit the ducts together and use either clamps or screws to secure the ducts to each early. When you get to the wall, use a duct cover to hide the hole on the inside side. You ’ ll have to fit the final part from the outside. This should include a release hood or cap, extending out far enough from the wall to meet local code. In most cases, that besides means ensuring it is at least 10 ’ off the grind .
Special Note:
If you ’ rhenium running your ducts to central ventilation, you ’ ll need a Y cleave for the ventilation. Make certain you check the size of the existing public discussion. then, when you get your duct to the public discussion, normally inside the wall, cut the primary ventilation shaft, install the Y schism, and install both the microwave vent and the master release to the lapp pipe .

What is a Self-Venting Microwave?

Most modern microwave ovens use recirculating vent. This means they recirculate air into the kitchen, normally after passing it through a filter. about all advanced microwaves fall under this class. This means that it contains a sports fan which pushes air out of the microwave, creating a vacuum, which sucks new vent in. This keeps the whole thing cool adequate to routine. however, it does mean that your kitchen will smell like anything you happen to be microwaving or bake .

Frequently Asked Questions

Venting an over-range microwave can be a batch of exercise. Chances are, you distillery have questions about how to do it. hopefully, this FAQ helps .

How much does it cost to vent a microwave outside? 

That fully depends on how far your microwave is from the vent and what your home is made of. In addition, if you ’ re in an urban area, local city code might force you to hire a contractor to do the influence. Check local code and then take steps yourself. If you ’ re doing the function yourself, already have the necessity tools, and only have to run ducts 20 or therefore feet, you ’ re probably looking at roughly $ 50 in costs. If you have to install multiple elbows, extra fans, and run the duct 40 feet, it will cost more than three times that .

Do you need a vent for over the range microwave?

Yes. The U.S. construction code, specifically the IECC Section R403.6 Mechanical Ventilation, makes it mandate to vent kitchen consume outside. If you don ’ thyroxine vent your over-the-range microwave outdoors, you are in rape of that code. While that presents long-run problems like difficulty selling your home, it can actually be dangerous .

Can you use flex duct for a microwave? 

You should not use flex vent for a microwave because it can increase your chances of fire. Why ? grease collects in the joints which can cause buildup and eventual fire risks. Most microwaves strongly recommend that you use a rigid duct rather. That ’ randomness important, because microwave vents are closer to the initial heat reservoir than range hoods – meaning they are more likely to pose a fire hazard if something does go wrong .


Most microwaves don ’ thymine ask vent. however, if yours does, venting it from an inside wall is a simple matter of running the duct pipe to the nearest external wall. alternatively, you can choose to run the duct pipe through the wall to the central public discussion .