How to Install a Built-In Microwave in a Cabinet

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Updated August 18, 2022

If you are shopping around for new kitchen appliances, you may wonder how to install a built-in microwave in a cabinet. Some of the best microwaves, like the Wolf vs Viking microwave drawer, are designed to fit over the range and sit inside of a dedicated enclosure. Keep reading to learn about built-in microwaves and the installation process.


  • Installing a built-in microwave is not a simple process and requires tools and some electrical know-how, unlike a countertop microwave that only needs counter space.
  • Consider hiring a professional, but if you are deadset on doing it yourself, make sure you have two or three people on hand.
  • Each make and model is different and may require a specific and unique installation procedure.

What is a Built-in Microwave?

A built-in microwave has many names, including a range microwave, an over-the-range microwave, or even a drawer microwave. A microwave can even be mounted on a wall. Typically, these microwave ovens rest above the oven range in a dedicated enclosure. They operate in contrast to countertop models, which do not need cabinet space, a trim kit, microwave vents, or anything else.

Insider Tip

Take your time with this installation, as a professional installation will result in safer operation and a longer overall lifespan.

How to Install a Built-in Microwave

Tools Needed: Phillips screwdriver, flat-blade screwdriver, measuring tape, level, drill, various drill bits

There are many ways to install a microwave, but built-in microwaves require a specialized process, as there are tools and multiple steps involved. Some consumers may also opt for a professional when it comes to installation.

STEP 1 Measure the Cabinet Opening

  1. No matter where the microwave oven will be placed, you will have to measure the cabinet opening before installation to ensure compliance.
  2. Use your tape measure to size out the depth, length, height, and width of the cabinet.
  3. Make sure to include around three inches of clearance above the cabinet opening and one inch of clearance below.
  4. Keep these measurements handy as you shop for your built-in microwave.

STEP 2Confirm Electrical Supply

  1. Make sure the cabinet has ready access to an electrical outlet with the proper voltage for your microwave.
  2. If the outlet is far away, purchase an extension cord and try to tuck it out of the way.
  3. Any extension cord will take up extra room at the back of the cabinet, so consider that.

SKIP 3 Assemble and Install the Spacer Kit

  1. Built-in microwaves should ship with a dedicated spacer kit to allow them to sit comfortably inside of your cabinet or related enclosure.
  2. The specific process of building this spacer kit will differ depending on the make and model of your microwave oven.
  3. The process typically includes aligning a spacer bar at the bottom trim and securing it with screws.
  4. Do the same thing for the opposite spacer bar.
  5. Drill through the mounting holes in the spacer bars to create pilot holes using whatever method indicated in the instructions. Insert the appropriate screws.
  6. Tighten these screws with a screwdriver, though take caution not to overtighten the screws.

STEP 4 Unpack the Microwave and Get it Ready

  1. Methodically unpack your new microwave, removing any packaging and setting aside any components and the instructions.
  2. If the microwave is heavy, make sure to have another person on hand for the rest of the installation process.
  3. Once unpacked, rest the microwave near the cabinet enclosure on a table or even a pile of cardboard.

STEP 5 Connect the Wiring

  1. Some built-in microwaves can simply be plugged into a power outlet, while others will require some light electrical work.
  2. Wear safety gloves and turn off the power via the fusebox before messing with actual electrical circuit boxes.
  3. Secure any wires to the junction box as indicated in the instructions, or simply plug the power cord into the extension cord or into the power outlet itself.

STEP 6 Place and Install the Microwave

  1. Now it is time to gently insert the microwave into the cabinet or enclosure.
  2. Have two or more people for this process.
  3. Align the microwave oven with the spacer bars.
  4. Open the microwave door and push against the front frame until it is fully inserted into the cabinet, making sure it is centered.
  5. Affix the microwave to the mounting bracket via whatever method is indicated in the instructions.
  6. Insert the rotating tray according to the instructions, and get ready to cook.
  7. Later on, you may want to learn how to clean a microwave with lemons or via other methods.


Do built-in microwaves need ventilation?

Yes, in most cases this major appliance will need ventilation of some kind.

How long do built-in microwaves last?

A built-in microwave oven should last ten years or so, depending on how often you maintain it and how accurately it has been installed. Be sure to use a trim kit to get that right and pay special attention to the power cord.

Are built-in microwaves safe?

Yes, built-in microwaves and wall ovens are safe no matter where they are placed, including upper cabinets, so long as they are installed correctly and include ventilation.

STAT: In 1947, Raytheon built the “Radarange”, the first commercially available microwave oven. (source)

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