How to Install an Over the Range Microwave

There will come a time when those reliable built-in appliances aren't so reliable anymore and it's time to replace them. If you're looking for some help with how to install an over-the-range microwave to replace an existing one that needs to retire, we put this guide together for you. 

Microwave installation is a relatively easy do-it-yourself project that you can accomplish in just a few hours time, with a little help. It may require heavy lifting and possibly some electrical work, however, so don't hesitate to hire the professionals if that is more your speed. Keep reading to get an idea of what over the range microwave installation may entail.

Before Installation

Kitchen appliances are important to keep updated and in efficient working condition, and some are more complicated than others to safely replace. Over the range microwave installation is a multi-step process. It can take up some floor space in your kitchen, and a few hours of your time, so it's a good idea to be prepared. 

Among the first considerations is the location of the over the range microwave. The wall where it is to be installed should be easily accessed, which may require moving the range out of the way to open up the floor space immediately under where you will be working. Microwave installation can require multiple people, and even a ladder, so prepare enough room to safely work. 

Next, you should have access to the new microwave. Remove it from the box and consult the included instruction manual to be sure you have all required parts. Check that the electrical cord is long enough to reach the electrical outlet after microwave installation. 

If there isn’t an electrical outlet within safe reach of the electrical cord, you will need to install an electrical outlet near the microwave. This is usually in the cupboard over the microwave, but can also be along the wall under it and a safe distance from the heat of the stove top.

With the microwave out of the box, take note of the vent setup at the back of the appliance. Consult the manual for the model specific instructions on how to install over the range microwave venting properly. Be sure all parts required for connecting the vents are at hand before getting started.

An over-the-range microwave must be vented, so have a plan in place, whether the microwave will need to be attached to existing ventilation, or has the ability to vent out the front of the appliance. You can install a new vent or call in a contractor for more complicated locations, such as adding a vent outlet or moving the electrical wiring.

Tools and Materials to Have on Hand

Make sure these items are ready to be used before you begin any part of the installation process.

Tools

• Drill & matching bits
• Stud finder
• Level
• Tape measure
• Tin snips
• Gloves
• Sturdy step stool or ladder

Materials

• A new Over the Range Microwave
• Toggle bolts, or drywall anchor bolts
• Painters tape
• Wood blocks or planks
• Drop cloth

Measurements

Before getting started with your over the range microwave installation, there are multiple measurements required to ensure the right fit. This includes measuring the width, height, and depth of the existing cupboard space the microwave will be installed into. Check that the new microwave can be installed below any cupboard edging and that the door will have room to open freely. The microwave dimensions should match with minimal overhang to ensure it installs securely.

Measure the distance between the stove top and the lowermost edge of the microwave. Manufacturer instructions should suggest the minimum height required for different types of ranges. This is often a minimum distance of 18 inches between the countertop and the lower edge of the upper cabinet or over the range microwave. 

Local codes and manufacturer instructions may vary, so measure and plan the installation carefully. The National Kitchen & Bath Association recommends the bottom edge of the microwave be installed at a height no more than 54 inches, or 4.5 feet, from the floor to be sure the microwave can be safely used. The typical cooktop height is 36 inches from the floor, allowing at least 18 inches distance between the cooktop and microwave edge at a 54 inch height.

Studs and Reframing

It is a good idea when preparing to install a microwave over a stove to mark off the wall studs behind the wall where the microwave will be mounted. Use a stud finder and mark the wall over the studs going down the height of the microwave. The microwave mounting bracket should be installed into at least two studs. 

If there aren't easily accessible studs, consider reframing behind the wall. Toggle bolts or drywall anchors may also be used if reframing isn't an option.

Reframing requires removing the drywall and exposing a large section of the interior wall in order to install 2x4 boards that can mount horizontally between the existing wall studs. This means removing the insulation, so use a drop cloth under the work area, wear gloves, and be careful handling the pieces of wall board as you remove it. Secure the 2x4 between the wall stud framing as-needed where the microwave mounting bracket will be installed. Replace the insulation and then the wallboard. 

Reframing will require extra time for repairing the wall and painting over the repairs. It can be more advanced than your average DIY project, so don't hesitate to hire a professional for complicated installations.

Recessed Cabinets

Another tricky kind of microwave installation to plan for are recessed edges on the cabinet the over the range microwave will be installed into. These can complicate any microwave installation project because they don't allow the microwave to fit securely against the cabinet without a little help to keep the bolts in place. 

When it comes to how to install a microwave into a recessed cabinet, you'll need a plank of wood or multiple blocks of wood that create the same depth as the front decorative edge of the cabinet to make sure the microwave door opens below the cabinet front. These can then be glued into place along the cabinet base, behind the recessed edge. They should be screwed into the cabinet in the later stages of the microwave installation after the microwave has been bolted in place from the cabinets’ inside surface.

How to Remove the Existing Microwave

For most new microwaves, you have to learn how to remove and install an over the range microwave. It is just a few extra steps, but you should enlist someone's help in supporting the weight of a microwave as you work to avoid damaging the wall, cabinets, or yourself.

1. Unplug the microwave power cord from the wall outlet. This is usually located in the cupboard over the microwave. Also disconnect any visible vent connections if needed.
2. While a helper supports the microwave from underneath, unscrew the bolts that hold the appliance frame to the underside of the cabinet. You access these screws from inside the upper cabinet.
3. Tilt the microwave forward and lift at the back edge to remove it from the mounting bracket on the wall.
4. Feed the electrical cord through the cabinet and remove the microwave from the wall. Set the microwave aside somewhere out of the way of your working area.
5. Remove the existing mounting bracket. They should easily unscrew from the wall. The mounting brackets will be different between models and should not be reused in case of unseen damage from age.

How to Install the New Mounting Bracket

The next step in over the range microwave installation is to install the new microwave mounting bracket. Many microwave manufacturers will have the mounting bracket already installed on the back of the microwave when you take it out of the box, so consult the instruction manual to familiarize yourself with the different included parts and be sure the mounting bracket is in place.

1. Remove the new bracket from the microwave if necessary.
2. Check for the wall studs and mark their locations down the wall under the microwave installation point. Verify that at least two wall studs are positioned near the microwave installation area.
3. Most microwave manufacturers include paper templates as a guide for where to drill bolt holes in the wall and cabinet. Tape the paper templates in place on the wall and on the underside of the cabinets. Make sure the template guides are centered and level, and lineup with your measurements and wall studs before you begin. 
4. Mark and drill out the holes for the electrical cords and any necessary adjustments to the vent holes.
5. Mark the screw holes over the wall studs and pre-drill pilot holes.
6. Remove the paper template from the wall and install the mounting bracket using the pre-drilled pilot holes. If there isn't a wall stud at that point, use a toggle bolt or drywall anchor to secure it.

How to Install a Microwave Over the Range With Vent

The last step in how to install a microwave is, of course, securing the microwave in place on the wall. For this part of the process, enlist someone to help hold the microwave in place as you secure it to the cabinet.

1. Using the paper template taped to the underside of the cabinet, drill pilot holes for the screws used to mount the microwave to the cabinet.
2. If the cabinet has a recessed front edge, add blocks to the bottom of the recessed cabinet where the paper template indicates pilot holes for mounting the microwave. Once the filler blocks are glued and secured in place, allow them to dry. Drill the pilot holes through the blocks and the cabinet using the paper template.
3. Adjust the microwave vent placement at the back of the microwave so it will line up with the vent in the wall or the vent pipes above the microwave. The vent placement will be unique to each model, so check the installation requirements from the microwave’s included manual. Line the vent up carefully, or be sure the microwave has a forward facing vent if there is no vent outlet at the cabinet where it is to be installed.
4. Thread the electrical cord through the hole in the cabinet. Do not plug it in yet.
5. With help, lift the back edge of the microwave to fit into the mounting brackets on the wall. It is not secure yet, so do not leave it unsupported.
6. Using the pre-drilled pilot holes, bolt the microwave frame into the bottom of the overhead cabinet. Start with the holes toward the front edge of the cabinet first and then secure the back. Check that all bolts are fastened, but not over tightened.
7. Check that the microwave door has clearance to open without hitting the cabinet and that everything is easily accessible. Plug it in and test that the microwave works.