What you need to know before you start

A microwave and a range hood do different jobs. A microwave heats food; a range hood removes steam, smoke, and cooking odors from your kitchen. If you want to remove the microwave and install a range hood in its place, you are changing your kitchen's ventilation system, not just swapping one appliance for another.

The main obstacle is usually the ductwork. Most microwaves sit above the stove and vent outside through the wall or roof — but not all of them do. Some recirculate air back into the kitchen instead of venting it out. Before you remove anything, find out whether your microwave vents to the outside or recirculates. If it recirculates, you will need to run new ductwork to the outside to make the range hood work properly.

The second issue is the electrical connection. Microwaves plug into a standard outlet. Range hoods usually need a dedicated 120-volt circuit, and some models need 240 volts. You may need an electrician to run a new circuit from your breaker box.

Key Takeaways

  • Check whether your current microwave vents outside or recirculates air back into the kitchen — this determines whether you can reuse the existing ductwork.
  • Range hoods need a dedicated electrical circuit, which may require hiring an electrician to run new wiring from your breaker box.
  • The space above your stove may not be deep enough for a range hood, especially if the microwave was shallow — measure the depth before you buy.
  • If your microwave vents outside, you can often reuse that duct path, but you will need to disconnect the microwave's vent damper and connect the range hood's duct instead.
  • Removing the microwave and installing the hood usually takes a full day if you already have the right electrical circuit in place.

Determine how your microwave currently vents

Look at the back of your microwave. If you see a metal duct or flexible ductwork running from the back toward the wall or ceiling, your microwave vents outside. If you see nothing — or if the microwave is sealed on the back — it recirculates. You can also check the model number on the microwave's nameplate and search the manufacturer's manual online to confirm.

If your microwave vents outside, you have a significant advantage: the ductwork path already exists. You can disconnect the microwave's duct and connect the range hood's duct to the same opening. If your microwave recirculates, you will need to hire a contractor or HVAC technician to run new ductwork from above the range hood to the outside of your home. This is the most expensive part of the job and can cost between $300 and $800 depending on how far the duct needs to travel and whether it has to go through walls or the attic.

Check the electrical requirements for your range hood

Most under-cabinet and wall-mounted range hoods run on 120 volts and plug into a standard outlet. However, they need a dedicated circuit — meaning that outlet cannot be shared with other appliances. Some high-powered range hoods, especially commercial-style models, require 240 volts, which means they need hardwired installation directly to your breaker box.

If your microwave is plugged into a shared outlet above the stove, that outlet is not suitable for a range hood. You will need to hire a licensed electrician to run a new circuit. The cost is typically $150 to $300 for a new 120-volt circuit, or $200 to $400 for a 240-volt circuit, depending on how far the electrician has to run the wire and whether your breaker box has available slots.

Before you hire an electrician, decide which range hood model you want and check its electrical specifications. The manual will state the voltage and amperage required. Bring that information to the electrician so they can size the circuit correctly.

Measure the space and choose a compatible range hood

Measure the width, depth, and height of the space where your microwave sits. Most microwaves are 30 inches wide and 15 to 18 inches deep. Range hoods come in many sizes, but the most common widths are 24, 30, 36, and 42 inches. The depth of a range hood is usually 16 to 20 inches, which may be deeper than your microwave.

If the space is too shallow, you have two options: choose a shallower range hood model, or remove some cabinetry above the microwave to make room. Removing cabinetry is a larger project and may affect the look of your kitchen, so measure carefully before you commit.

Also check the height. Your range hood needs to be at least 24 inches above the cooktop surface — some building codes require 30 inches. If your microwave was mounted lower, you may need to raise the hood or remove some of the cabinet structure above it.

Turn off the power and remove the microwave

Before you touch anything, turn off the circuit breaker that powers the microwave. Test the outlet with a voltage tester to confirm the power is off.

Unplug the microwave from the outlet. If it is hardwired instead of plugged in, you will need to disconnect the wires inside the junction box — turn off the breaker first, then remove the cover plate and disconnect the wires by loosening the wire nuts.

Next, disconnect the ductwork. If the microwave vents outside, loosen the clamp that holds the duct to the back of the microwave and slide the duct away. If the duct is sealed with foil tape, cut the tape with a utility knife first. Take a photo of how the duct is connected before you remove it — you will need to reconnect it to the range hood later.

Finally, remove the mounting bracket. Most microwaves are held to the wall or cabinet with four bolts. Use a socket wrench or adjustable wrench to remove them. Have someone help you lower the microwave safely — they are heavy and awkward to handle alone.

Install the range hood in the same space

Position the range hood in the opening and use a level to make sure it is straight. Mark the mounting holes on the wall or cabinet with a pencil. Drill pilot holes at each mark, then bolt the range hood to the wall or cabinet using the bolts that came with it.

If you are reusing the existing ductwork from the microwave, connect the range hood's duct collar to the duct using a duct clamp and seal the joint with foil tape. Make sure the duct is not kinked or crushed — a bent duct reduces airflow and makes the hood less effective.

If you had to run new ductwork because the microwave recirculated, the HVAC technician will have already installed the duct before you mount the hood. straightforward connect the hood's duct collar to the duct that is already in place.

Connect the electrical wiring. If the hood plugs in, plug it into the dedicated outlet. If it is hardwired, have the electrician make the final connections at the junction box — do not do this yourself unless you are licensed.

Test the hood and seal any gaps

Turn the breaker back on and test the range hood on all fan speeds. Listen for unusual noises and feel for airflow at the duct opening outside your home. If you do not feel air moving, the duct may be blocked or kinked.

Seal any gaps between the range hood and the cabinet or wall with caulk or foam weatherstripping. This prevents air leaks that reduce the hood's efficiency.

If the hood has a filter, install it according to the manual. Most range hoods use either a baffle filter or a mesh filter. Baffle filters last longer and are easier to clean; mesh filters are cheaper but need more frequent washing.

Frequently Asked Questions

Can I install a range hood if my microwave does not vent outside?

Yes, but you will need to run new ductwork to the outside. This is the most expensive part of the project. An HVAC contractor can assess your kitchen and give you a cost estimate. The duct usually runs through the attic or inside a wall to reach the nearest exterior wall or roof.

Do I need a permit to replace a microwave with a range hood?

Most jurisdictions require a permit for any work that involves running new electrical circuits or ductwork. Check with your local building department before you start. Permits usually cost $50 to $150 and take one to two weeks to process.

What if there is a cabinet directly above where the microwave was?

You will need to remove or relocate that cabinet to make room for the range hood. If the cabinet is attached to the wall, you can remove it by unbolting it from the studs. If it is part of a larger cabinet run, you may need a carpenter to modify the structure. This adds significant cost and complexity to the project.

How much does it cost to replace a microwave with a range hood?

The range hood itself costs $200 to $1,500 depending on size and features. Add $150 to $400 for a new electrical circuit, and $300 to $800 if you need new ductwork. Labor for installation is typically $200 to $500 if you hire a contractor. Total cost is usually $850 to $3,200.

Can I use the same outlet as the microwave for the range hood?

Not if that outlet is shared with other appliances. Range hoods need a dedicated circuit. If the outlet is already dedicated to the microwave alone, you can reuse it for the range hood as long as the hood's amperage requirement does not exceed the circuit's capacity — check both the hood's manual and the breaker label to confirm.