Microwave manufacturers produce different microwave designs for built-in cabinet holes and for countertop or open-concept settings. The design of each differs in terms of vent placement, as countertop microwaves do not have a wooden frame that surrounds the unit like built-in microwave designs. Despite the difference in designs, it is possible to install a countertop microwave in a cabinet unit if you do so cautiously. You will need to check countertop microwave clearance before putting a microwave in a cabinet or another built-in nook.
It is possible to install a countertop microwave in a built-in microwave hole, but you must do so carefully, as these two types of microwaves have different venting systems.
Before you begin, be sure that your microwave is not plugged in. It is very dangerous to make changes to an appliance while it is connected to live power. You can even turn the power off at the circuit breaker box to be certain you don't come into contact with electricty accidentally.
If your microwave is cumbersome or heavy, request the help of a friend or family member to help you move it. You should never attempt to tip a microwave or lift it on your own. Be sure that children and pets are safely away from your workspace while you prepare the microwave and move it.
Finally, make sure the door of the microwave is latched tightly when moving it. If it falls open in transit, you could injure yourself. Move any glass turntables that are located within the microwave, too, in case the door opens. This will prevent injuries or breaking parts of the microwave.
Checking Vent Placement
Examine the countertop microwave to locate all vents on the two sides, top and back panels. Since a countertop microwave is designed to rest on a countertop, the vents are often placed on the sides or top to ensure the vents have proper air space to clean out dust and expel hot air during operation. These vents cannot be covered in the built-in hole, as it may cause the microwave to overheat or malfunction.
DIY Built-In Microwave
Place the countertop microwave in the built-in hole. Adjust it so each vent area has at least 1 inch of space in front of it. Do not push the microwave all the way against the back panel of the cabinet, and do not force the microwave into the cabinet space if the side panels do not provide enough space for the vents.
Cabinet Wire Adjustments
The microwave must be plugged into a grounded electrical outlet, meaning you cannot use a power bar or an extension cord to make the microwave function. If there is an electrical outlet in the back of the cabinet panel, simply insert the cord there. If the outlet is present on a nearby wall, make a small cut in the cabinet's side panel so the cord fits through.
Cleaning and Maintenance
Remove the microwave from the built-in cabinet hole every three months or so to clean the microwave vents. Even though the appliance is designed for countertops, it still collects dust in the vents on the top, sides and back of the microwave. In addition, the cabinet's panels prevent the dust from flying out of the cabinet completely, so that it will not clean out automatically. Use a damp cloth when the microwave is turned off to remove obvious dust and particles from the vents.
Based in Toronto, Mary Jane has been writing for online magazines and databases since 2002. Her articles have appeared on the Simon & Schuster website and she received an editor's choice award in 2009. She holds a Master of Arts in psychology of language use from the University of Copenhagen in Denmark.