Most range hood installations fail in one of two places: the ductwork or the mounting height. Everything else — the wiring, the filter, the fan speed settings — is almost always straightforward by comparison. If you get those two things right from the start, the rest of the job tends to fall into place without much drama.
I want to walk you through this the way I’d actually do it in someone’s kitchen, not the sanitized version you’d get from a manufacturer’s manual. There are real decision points here — ducted versus ductless, wall mount versus under-cabinet, whether your existing ductwork is even usable — and getting those decisions right matters more than any single step in the process.
By the end of this, you’ll know exactly what to check before you buy the hood, what tools you actually need versus what’s optional, and where most DIY installs go sideways. This isn’t a two-hour job for most people, and I’ll be honest about that upfront rather than pretending otherwise.
Deciding Between Ducted and Ductless Before You Buy
This decision has to happen before the hood arrives, not after, because it changes what you’re buying entirely. A ducted range hood pulls air through ductwork and pushes it outside — through a wall cap or roof cap — which means it’s actually removing heat, grease, and moisture from your kitchen rather than just filtering and recirculating it. A ductless (recirculating) hood pulls air through a charcoal filter and blows it right back into the room. Ducted is almost always the better performer. If your kitchen already has ductwork from a previous hood, you’re in good shape — reuse it if the diameter and material are still sound. If you’re starting from zero and the range is on an interior wall with no easy path to the outside, ductless becomes the realistic option, even though it’s the compromise choice.
What surprised me was how often people assume ductless is just as good because the hood “looks the same” and has similar CFM ratings on the box. It isn’t. A recirculating filter traps grease reasonably well but does very little for heat and humidity, which matters a lot if you’re cooking with gas or doing anything that produces real steam.
If there’s any way to route ductwork to an exterior wall or through the roof, even if it means a slightly more involved install, it’s worth the extra effort. I’ve had people regret the ductless shortcut within a year, usually right around the time they notice condensation building on cabinet undersides.
Getting the Mounting Height Right
Mounting height is where measurements matter more than anywhere else in this project, and it depends on your range type. For gas ranges, manufacturers typically call for 30 to 36 inches above the cooktop surface. For electric or induction ranges, 24 to 30 inches is more common since there’s less open flame and heat to account for.
Check your specific hood’s installation manual for its exact range, because these aren’t universal numbers — I’ve seen premium hoods spec closer to 36 inches minimum even for electric ranges, purely based on their fan intake design.
Measure twice here. Mount too low and you risk heat damage to the hood itself, plus you’ll be constantly ducking under it. Mount too high and you lose a meaningful amount of suction efficiency — the hood simply can’t pull air from that far away as effectively, no matter how high the CFM rating says it should perform. Use a stud finder before you commit to a mounting point. Under-cabinet hoods usually mount directly into the cabinet bottom with long screws, which is fairly forgiving. Wall-mounted chimney-style hoods need to hit real structural support, and if there isn’t a stud where you need one, you’re looking at adding blocking behind the drywall before you can safely hang anything.
Cutting the Cabinet or Wall Opening
Once you know your mounting height and duct path, you’ll need to cut an opening for the ductwork to pass through — either up through the cabinet above an under-cabinet hood, or through the wall behind a chimney-style unit.
I’ve tested this myself enough times to have a strong opinion: use the mounting template that comes with the hood rather than eyeballing measurements off the box dimensions. Every manufacturer’s template accounts for slightly different duct collar placement, and guessing here is one of the most common reasons installs end up with a duct run that has an awkward, airflow-killing bend right where it exits the hood.
A hole saw sized to your duct diameter (typically 6 inches for most residential range hoods, though some low-profile units use smaller ducting) makes this cut cleanly. Cutting through cabinet material is usually straightforward. Cutting through exterior wall material for a wall cap is a bigger job — you’re dealing with siding or brick on the outside, insulation in the cavity, and you need to seal that opening properly once the duct is through, or you’ll get drafts and moisture problems that show up months later, not immediately.
Running the Ductwork
Rigid metal duct outperforms flexible duct almost every time, and this matters more than most people expect going in. Flexible duct is easier to work with in tight spaces, but every bend and every inch of that corrugated interior surface adds resistance, which quietly kills your CFM output before the air ever reaches outside. The first time I dealt with a hood that “wasn’t pulling air like it should,” the actual problem wasn’t the fan at all — it was 15 feet of flexible duct with three unnecessary bends in it, installed by someone trying to avoid cutting into a wall.
Keep the duct run as short and as straight as possible. Every 90-degree elbow you add is roughly equivalent to losing several feet of straight duct in terms of airflow resistance, so a run with two elbows performs meaningfully worse than the same length of duct with zero.
Seal every joint with foil tape rated for HVAC use — not standard duct tape, which despite the name breaks down over time and stops sealing. At the exterior termination point, install a wall cap or roof cap with a functioning backdraft damper. That damper is what keeps outside air, insects, and cold drafts from coming back through the duct when the hood isn’t running, and it’s a small part that gets skipped more often than it should.
Wiring the Hood Safely
Turn off the breaker before touching anything electrical, and confirm it’s actually off with a voltage tester rather than trusting the panel label, which is wrong in more houses than you’d think. Most range hoods run on a standard 120-volt circuit, either hardwired into a junction box above the cabinet or plugged into an outlet inside the cabinet itself, depending on the model and local code requirements in your area.
If you’re wiring into an existing junction box left over from a previous hood, check the wire condition before reusing it — older wiring, especially in homes built before certain code updates, can be undersized for a hood with a stronger motor and higher fan speed settings than what was originally installed. Connect wires with properly sized wire nuts, matching black to black, white to white, and ground to ground, and secure everything inside the junction box before you mount the hood body over it.
I’ve seen this go wrong when someone rushes the grounding connection specifically, treating it as optional because “the hood still works without it.” It works fine right up until there’s a fault, and that’s exactly the situation the ground wire exists for.
Mounting the Hood and Final Connections
With the duct run complete and wiring in place, mounting the hood body itself is usually the fastest part of the whole job. Under-cabinet hoods typically use a bracket that screws into the cabinet bottom, then the hood slides up and locks into place. Wall-mount chimney hoods often hang on a bracket secured to studs, with the decorative chimney piece attached afterward once the hood body is level and secure. Check level carefully before final tightening — even a slightly crooked hood becomes obvious the moment the kitchen lighting hits it at the wrong angle, and it’s much easier to adjust now than after everything’s fully secured.
Connect the duct collar on the hood to your ductwork run, sealing that connection with foil tape the same way you sealed the joints further down the line. Install the grease filter, restore power at the breaker, and test all fan speeds along with the light before you consider the job finished. From experience, the smarter move is running the fan on high for a few minutes right after installation and checking every duct joint by hand for airflow leaks — you’ll feel a leak far more reliably than you’ll see one.
What Most People Don’t Know
Most people assume that once ductwork exists in a wall, it’s automatically usable for a new hood. That’s usually wrong. Older ductwork, especially anything installed before the early 2000s in a lot of homes, is frequently undersized for modern hood CFM ratings — a common older standard was 3.25-by-10-inch rectangular duct, which chokes airflow badly on a hood rated for 400 CFM or higher.
If you’re reusing existing ductwork, it’s worth actually measuring it and checking it against your new hood’s minimum duct size requirement listed in the installation manual, rather than assuming compatibility because “there’s already a hole there.” Installing a powerful hood onto undersized ductwork doesn’t just reduce performance — it can create enough backpressure to strain the fan motor over time, shortening the life of a hood that would otherwise last well over a decade.
What Comes Next
A range hood installed correctly should run quietly, clear cooking exhaust efficiently, and need nothing from you beyond regular filter cleaning for years. If yours is rattling, underperforming, or leaking air at the joints after installation, go back through the duct run first — that’s where the vast majority of post-install problems actually live, not in the hood itself. Get the ducting and mounting height right, and everything downstream of that tends to take care of itself.
