Kitchen Range Hood Install: What You Actually Need

Sizing your range hood

Rule of thumb: 100 CFM per linear foot of cooktop, or 10× the BTU rating of a gas range divided by 100. A 36" gas range at 60,000 BTU needs at least 600 CFM. Higher CFM = louder + more make-up air needed. Homes built after 2010 with tight envelopes often need make-up air for hoods over 400 CFM.

Ducted vs. ductless

Ducted is always better if you can route it. Straight-up through the cabinet and roof is best; 90-degree elbows kill CFM.

Ductless (charcoal filter) is a fallback for interior walls with no exterior access. Filters need replacement every 3–6 months.

Materials list

• Range hood (verify width matches cooktop within 3")
• Rigid metal duct (avoid flex — cuts CFM by 30–50%)
• Duct clamps, mastic or foil tape (not cloth duct tape)
• Roof or wall cap with backdraft damper
• Flashing (roof) or trim ring (wall)
• Junction box + 14/2 or 12/2 romex (verify amperage requirement on the hood spec)
• Toggle bolts or lag screws sized to your cabinet or ceiling framing
• If cabinet mods needed: hole saw sized to duct diameter, straightedge, jigsaw

Electrical is a licensed-pro job

If you're running a new circuit or modifying the panel, hire a licensed electrician. Matly flags this in its materials list. If you're plugging into an existing outlet above the cabinet, you can typically DIY the mechanical install.