Does a Microwave Need to Be Vented?

Modern kitchens have concealed cabinets for all appliances. It makes the kitchen look neat and spacious. However, it may not be safe for all devices, like the microwave. First, know if your microwave needs to be vented before you install it in a concealed cabinet.

After you find out the safety of the microwave in the cabinet, install it the right way. Ask a professional to install it if you have an Over-the-Range (OTR) microwave.

Each microwave needs to be vented. Ventilation ensures the microwave is safe and works efficiently. Ventilation is necessary if the microwave model lacks a built-in vent system.

Why a Microwave needs to be Vented

Microwave ovens use vibration to heat and cook food. The microwaves hit the water within the food. As a result, the water molecules vibrate to create heat. The heat cooks food from within.

As the heat builds up due to vibration, the air in the oven expands. The air will blow up the oven if there are no air outlets. Thus, vents on the side of the tip of the microwave oven allow the expanding air to escape.

You need enough room for these vents to release hot air. If you have to install your microwave in a concealed cabinet, ensure it has an excellent system to allow the hot air to escape. When the air stays around the microwave, it can damage its system and reduce efficiency.

Check your microwave manual for minimum clearance and ventilation needs. Also, follow the installation guidelines to enjoy your microwave oven for a long time.

What Happens if a Microwave Lacks Vents

A microwave with vents cools well after use. Thus, it keeps the appliance durable and operates efficiently. But have you thought about what could happen if a microwave lacks ventilation?

When you block a microwave’s ventilations, hot air will lack an escape route. Thus, your appliance will overheat. It will also trap odors, smoke, and steam that must leave the device when and after use.

When you trap all the odor, steam, heat, and smoke, it will be undesirable to warm your food in the appliance. The smell will travel around the kitchen over time, and you’ll have a stinky cooking place.

If you fail to release heat from the microwave, the magnetron that emits the microwaves will absorb it. It will reduce the efficiency, and your microwave oven will fail, get faults, or be damaged. That will mean you’ll have to buy another microwave oven. Also, the constant overheating will make the appliance faulty.

Ventilation Around a Microwave

Over-the-range microwaves have their vents at the top front. On the other hand, countertop microwaves have vents on the sides, back, or at the top.

Depending on the manufacturer’s instructions, you must leave a space around a microwave. A 3-inch gap around the microwave is the ideal vent space you need. However, you can have a larger gap as per brand specifications.

If you place your microwave in a cabinet, ensure you leave a space at the back. Remember to elevate it so that it leaves room at the bottom.

Does a Countertop Microwave Need to be Vented?

Yes, your countertop microwave needs to be vented. Although you place them open most of the time, they will still need to release hot air, odors, and smoke from within. Thus, you must clear all the vents at the back, top, or sides. Follow the general instructions below to prolong the life of your microwave.

  •       Leave at least 1-inch clearance at the back.
  •       Leave at least a 3-inch clearance at the sides.
  •       The top should be open if possible. Avoid placing objects on top of a microwave.
  •       If you put the microwave inside a cabinet, leave it at least 3 inches from the door.
  •       Ensure there’s a 2-inch gap between the microwave and the stove.
  •       Never fold the microwave’s feet, as it may hinder proper ventilation.

Does Over the Range Microwave need to be Vented?

People think they don’t need ventilation when the microwave is on the stovetop. But to prolong its life, it needs proper ventilation. It may require more ventilation than a countertop microwave since it gets heat inside and outside.

If you use a microwave many times a day, it needs more ventilation than one that rests most of the time. An appliance heats up faster when under constant use. Thus cooling is essential for maximum efficiency.

How to Vent Over the Range Microwaves

There are two ways you can vent an OTR microwave. You can install a recirculating vent or an external exhaust system. Any method will keep your microwave cool and efficient for a long time.

A recirculation system in a microwave will filter pollutants, toxins, odor, and smoke before releasing the air in the kitchen via its exhaust system. Thus, the filter will have charcoal to keep the air in the kitchen odorless. Therefore, the system is ductless and built-in. Also, it’s located at the bottom of the appliance. Such microwaves are best when your kitchen doesn’t have room to install a duct vent. They are also easier to install than their counterparts with external exhaust systems.

You can also get a microwave with an external exhaust system. That means they have ductwork that expels unwanted odor, steam, heat, toxins, and smoke from your kitchen through an external exhaust fan. The system is easy to install when you have a range hood duct. However, it’s costly to install when you need to drill through the wall to create a new duct vent. Also, you’ll need to check if the local laws allow external venting systems.

Microwaves with recirculating systems are common since they are easy to install. Also, you can move the microwave easier without the help of a technician. An OTR microwave with an external exhaust vent needs a technician to install it. Also, you can’t move them after installation. However, they are more durable and efficient than microwaves with a recirculating vent system.

Requirements for Microwave Venting

A microwave with recirculating vents has its systems within the microwave. It makes it easy for a technician to install it. Thus, there are no plumbing restrictions or requirements for installing and using it. However, you must place the microwave at least 30 inches from your stove.

Choosing a microwave with an external exhaust system must conform to plumbing and area codes. You’ll need to install a duct to take the fumes outside the building.

You’ll have to drill the house if your house doesn’t have a range duct. Before doing so, you’ll need permission from the house management. Also, you’ll need to follow the building standards and codes before you start the work. You’ll need to assess whether the building can carry a line through its wall.

When you seek permission, you’ll need to know the danger zones you must avoid. Also, check whether it’s safe to droll the house and if water pipes are running within the walls.

Before you drill the house, ensure you are comfortable with your chosen spot. Once you install it, you can’t move the microwave unless you relocate to a different area. The microwave should remain fixed in one place as long as you lie in that house. Moving the microwave means you must ask permission again to redo the process.

Safety Precautions when Installing and Using a Microwave

  •  Ensure you install the microwave oven at an accessible height. The door should be below your face, and you shouldn’t stretch your hands when using the microwave. Installing the microwave too high may lead to accidental spills and burns from hot beverages.
  • Place the microwave far from flammable objects like clothes, wood, and paper. It’s rare to experience microwave fires, but they can damage inflammable objects near them.
  • When you choose an OTR microwave, ensure you have enough room to work on your stovetop. Experts recommend you leave at least 30 inches from the stove to the bottom of your microwave.
  • Use microwave-safe containers to warm your foods. You can check the stickers on containers before buying them. It saves you time to research materials you can use in the microwave. Avoid using metallic containers as they may cause explosions.
  • Always stir the food after reheating it in the microwave. It ensures you distribute the heat evenly in your food.
  • Wipe off any spills in your microwave immediately after they happen. Also, ensure no spills or splatter gets to the door area. Their accumulation forms a wedge that prevents the door from closing. Consequently, microwave energy escapes through the door while heating food.
  • Never use a microwave with a faulty door. The door sensor is defective if the fan, lights, and other turntables work with the door open.
  • Unplug your microwave from the power source when cleaning. Also, keep the power outlet free from moisture.
  • Turn off the power as soon as you experience a microwave fire. Don’t touch the appliance until the fire has died down. Call the fire department if the fire starts to spread.


Yes, all microwaves need to be vented. The vents expel fumes, odors, and hot air from the microwave preventing it from heating up. Thus, your appliance remains in good condition for a long time.

You can choose a microwave depending on its ventilation type. However, you need to check the requirements and restrictions within your area.

Countertop microwaves and OTR microwaves with a recirculating system are easy to install. Also, their venting systems are within the microwaves, making it easier to move the microwave at different spots in the house. On the other hand, OTR microwaves with external vent systems are permanent once installed. Ensure you don’t block the ventilation of any microwave you choose to use.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.