What You Need Before You Start

Installing a range hood under cabinet requires three things: the right tools, accurate measurements, and a clear path to ductwork or a vent. Most under-cabinet hoods mount directly to the underside of your cabinet using brackets and screws — no special carpentry skills needed, but you do need to know where your ducts run and whether your cabinet can support the weight.

Gather a drill with bits, a level, a tape measure, a stud finder, and a screwdriver before you begin. Check your range hood manual for the exact bracket locations and weight capacity. If your cabinet is older or made of thin material, you may need to reinforce it with backing boards before mounting.

The hardest part is usually the ductwork. Under-cabinet hoods vent either through the wall behind your stove or up through the cabinet into the attic or roof. If you are venting horizontally through the wall, you need a clear path and a vent cap on the outside. If you are venting up, you need access above the cabinet and a way to route the duct without kinks or long runs.

Key Takeaways

  • Measure the space between your cabinet bottom and stovetop — most hoods need 24 to 30 inches of clearance, and too little will reduce airflow and create a fire hazard.
  • Locate studs or solid cabinet framing before drilling, because the hood's weight must be supported by wood, not drywall alone.
  • Plan your ductwork route before you mount the hood — horizontal venting through the wall is simpler than vertical venting through the cabinet.
  • Use the brackets and hardware that came with your hood, and follow the manual's spacing exactly, because uneven mounting can cause vibration and noise.

Measuring and Marking the Mounting Points

Start by measuring the distance from the top of your stove to the bottom of the cabinet. Most under-cabinet hoods are designed for 24 to 30 inches of clearance. If your space is smaller, the hood will not draw air properly and may create a fire hazard. If it is larger, the hood will be less efficient. Check your manual for the exact minimum and maximum heights.

Next, find the center of your stove and mark it on the cabinet bottom with a pencil. Measure out from that center point to locate the mounting bracket holes. Your manual will show you exactly where these holes go — usually two or four points depending on the hood size. Use a level to may support your marks are straight across, not tilted.

Before you drill, use a stud finder to locate the solid framing inside the cabinet. The hood's weight — typically 40 to 80 pounds — must rest on wood, not on drywall or thin plywood. If the mounting points fall on empty space, you will need to install a backing board (a piece of 2-by-4 or plywood) between the cabinet and the mounting surface.

Drilling and Installing the Brackets

Drill pilot holes at each marked point using a bit slightly smaller than your mounting screws. Pilot holes prevent the wood from splitting and make it easier to drive the screws straight. If you are drilling through thick cabinet material, use a drill with a clutch setting to avoid overdriving and cracking the wood.

Insert the brackets into the pilot holes and hand-tighten the screws first. Do not use a power drill for this step — you need to feel the resistance and stop before the screw is fully seated. Once all brackets are hand-tight, use a level to check that the mounting surface is perfectly horizontal. If it is tilted, loosen the screws on the high side and shim underneath with washers or thin wood shims until the level reads true.

After the brackets are level, tighten all screws firmly with a power drill or screwdriver. The hood should not move or flex when you push on it. If it does, the brackets are not tight enough or the mounting surface is not solid enough to support the weight.

Connecting the Ductwork

The duct connection is where most installations go wrong. Under-cabinet hoods have a duct collar — usually a round or rectangular opening — on the top or back. Your ductwork must connect to this collar with as few bends as possible. Long runs with multiple elbows reduce airflow and increase noise.

If you are venting horizontally through the wall, measure the distance from the hood collar to the outside wall. Use rigid ductwork (metal pipe) rather than flexible ductwork when possible — it resists crushing and moves air more efficiently. Run the duct as straight as possible, and use no more than one 90-degree elbow. At the outside wall, install a vent cap with a damper that closes when the hood is off, preventing cold air from flowing back into your kitchen.

If you are venting vertically through the cabinet into the attic or roof, you will need access above the cabinet. Run the duct straight up and find it with metal straps every 4 feet. Make sure the duct does not rest on insulation or touch any electrical wiring. At the roof or attic exit, install a vent cap and seal around it with roofing cement to prevent leaks.

Sealing and Testing the Installation

Once the ductwork is connected, seal all joints with metal duct tape or mastic sealant. Duct tape degrades over time and can fail, so mastic is the better choice for a long-lasting seal. Wrap the tape or explore the sealant around the entire circumference of each joint, including where the duct meets the hood collar.

Before you close up the cabinet, turn on the hood and listen for rattling or whistling. A little noise is normal, but loud rattling usually means the duct is vibrating against the cabinet or framing. If this happens, add rubber isolation straps or foam padding between the duct and the wood to dampen the vibration.

Check that air is flowing out of the vent cap on the outside of your house. Hold a piece of tissue near the vent opening — it should move noticeably when the hood is on high. If the airflow is weak, the duct may be kinked, blocked, or too long for the hood's motor to push air through.

Securing the Hood to the Brackets

Most under-cabinet hoods slide onto the brackets or bolt to them. Check your manual for the exact method. If your hood slides on, align the mounting slots on the hood with the bracket tabs and slide the hood forward until it seats fully. If it bolts on, use the bolts provided and tighten them evenly so the hood does not tilt.

Once the hood is mounted, check that it is level from side to side and front to back. A tilted hood will not drain condensation properly and may vibrate. If it is not level, loosen the mounting bolts, shim underneath with washers, and retighten.

Connect the power cord to a dedicated outlet or have an electrician wire it to a switch. Do not use an extension cord or plug the hood into the same outlet as your microwave or other high-draw appliances. If the hood has a light, test it along with the fan motor before you consider the job complete.

Common Problems and How to Fix Them

If the hood vibrates loudly during operation, the mounting brackets are not tight or the ductwork is vibrating. Tighten all bolts and screws, and add rubber isolation straps around the duct where it touches the cabinet framing. If the vibration continues, the hood motor itself may be failing and will need replacement.

If the hood does not pull air effectively, the ductwork is likely too long, has too many bends, or is partially blocked. Check the vent cap on the outside to make sure it is not clogged with lint or debris. If the cap is clear, trace the duct back to the hood and look for kinks or crushing. Straighten any bends and remove any blockages. If the duct is longer than 25 feet or has more than two elbows, the hood may not be powerful enough for that run — you may need a more powerful model.

If the hood leaks water or grease, the ductwork seals are failing or condensation is dripping back into the hood. Reseal all joints with mastic and make sure the duct slopes slightly downward toward the outside vent cap so water drains out, not back into the hood. If the problem persists, the hood may need a condensation trap or a longer duct run to allow moisture to evaporate before it reaches the cap.

Frequently Asked Questions

Can I install a range hood if my cabinet is made of particleboard?

Particleboard is weaker than solid wood and may not hold the hood's weight over time. If your cabinet is particleboard, reinforce the mounting area with a backing board — a piece of 3/4-inch plywood or solid wood screwed to the cabinet framing. This distributes the hood's weight across a larger area and prevents the particleboard from sagging or cracking.

What is the minimum clearance between the hood and the stove?

Most manufacturers require 24 to 30 inches of clearance between the top of the stove and the bottom of the hood. Check your manual for the exact minimum — too little clearance reduces airflow and creates a fire hazard. Too much clearance makes the hood less effective at capturing steam and smoke.

Do I need a professional electrician to wire the hood?

If your hood plugs into an outlet, you can do it yourself as long as the outlet is within reach of the power cord. If the hood needs to be hardwired to a switch or circuit, hire a licensed electrician. Improper wiring can create a fire hazard or void the hood's warranty.

Can I vent the hood into the attic instead of outside?

No. Venting into the attic or crawlspace pushes moisture and cooking odors into those spaces, where they can cause mold, rot, and structural damage. Always vent to the outside through a vent cap. The only exception is a recirculating hood with a charcoal filter, which pulls air through the filter and back into the kitchen — but these are less effective at removing moisture and odors.

How often should I replace the range hood filter?

Metal mesh filters should be cleaned every month or two, depending on how much you cook. Wash them in hot soapy water or run them through the dishwasher. Charcoal filters in recirculating hoods cannot be cleaned and must be replaced every three to six months. Check your manual for the exact replacement schedule and filter part number.