Specs are compiled from manufacturer listings and verified buyer reviews and can change over time — please confirm the key details on the product page before buying.
A greenhouse that bakes in the summer sun isn’t a sanctuary for your plants — it’s an oven. Without a powerful exhaust fan to pull out the stifling, humid air and draw in fresh, cooler air, your tomatoes wilt, your seedlings stretch, and the whole space becomes a breeding ground for mold. The right fan changes everything, turning a sweatbox back into a thriving ecosystem.
I’m Rikta — the founder and writer behind Lawn Gear Lab. This guide is built by comparing the manufacturers’ published specifications and the patterns across verified customer reviews, so you get each pick’s real strengths and trade-offs instead of marketing spin.
You need an exhaust fan for greenhouse that keeps your plants from overheating and controls humidity. The right choice depends on matching airflow (measured in CFM, or cubic feet per minute), fan size, and smart controls to your greenhouse’s exact square footage.
Our Picks at a Glance
How To Choose The Best Exhaust Fan For Greenhouse
Picking the right fan starts with two simple questions: how big is your greenhouse, and how much do you want the fan to think for itself? The answers steer you to the right CFM, size, and control type.
Match CFM to Your Square Footage
CFM (cubic feet per minute) measures how much air the fan moves. A good rule is to aim for a fan that can exchange the entire volume of your greenhouse air in about one minute. For a small 100-square-foot shed, 600 to 1000 CFM is plenty. For a large 20-foot by 50-foot structure, you are looking at over 3000 CFM to keep the air fresh.
Shutters: More Than a Cover
Automatic gravity shutters are a must for a greenhouse fan. They open when the fan is running and close tightly when it stops. This keeps out rain, cold drafts, pests, and debris during the off hours, which is critical for a stable growing environment.
Smart Controls vs. Simple Switches
Some fans come with a basic on/off switch, which forces you to monitor the temperature yourself. A thermostat control lets you set a target temperature (say, 85°F), and the fan kicks on automatically to keep things cool. More advanced models also track humidity, which is a huge help in preventing mildew during the night.
DC Motors: Quiet and Efficient
A DC (direct current) motor uses less electricity, runs significantly quieter, and often offers variable speed control compared to a traditional AC motor. If your greenhouse is near a house window or a quiet sitting area, a DC fan is worth the small premium.
Quick Comparison
| Model | Best For | Airflow (CFM) | Motor Type | Controls | Amazon |
|---|---|---|---|---|---|
| iLIVING 24″ ILG8SF24V-T★ Best Overall | Massive Greenhouses | N/A | AC | Thermostat + 3-Speed | Amazon |
| AC Infinity AIRLIFT T16Smart Tech Pick | Smart Control | 2560 cfm | EC | WiFi App + Temp/Humidity | Amazon |
| iLIVING 20″ ILG8SF20V-STTop Performer | High Coverage | 3368 cfm | AC | Thermostat + Variable Speed | Amazon |
| Amico 12″ DC | Energy Efficiency | 1282 cfm | DC | Thermostat + 8-Speed | Amazon |
| addlon 16″ EC | Quiet Operation | 1700 cfm | EC | Remote + 8-Speed + Timer | Amazon |
| VENTISOL 20″ | Budget Power | 3500 cfm | AC | On/Off Switch | Amazon |
| KEN BROWN 20″ | Simple Air Movement | 3500 cfm | AC | On/Off Switch | Amazon |
| HG Power 10″ | Small Sheds & Coops | 647 cfm | AC | On/Off Switch | Amazon |
In‑Depth Reviews
1. iLIVING ILG8SF24V-T 24″ Shutter Exhaust Fan
Our pick — over 4.5★ from 850+ verified ratings; the strongest balance of quality and price.
The heavyweight champ that clears a 20×50 space in minutes flat.
That sheer volume is what makes it the right fit for serious greenhouse owners with large structures. It comes with a built-in thermostat that you can set anywhere from 32°F to 130°F, so the fan runs only when it’s needed. The 3-speed switch lets you dial in airflow from a gentle exchange to full hurricane mode.
The iLIVING 24-inch ILG8SF24V-T uses high-grade aluminum shutters that resist moisture and heat better than cheaper models — important when your fan is mounted through a wall exposed to the elements. Buyers report it is surprisingly quiet for its size and that it moves “more air than you think it does.” One buyer ran it daily for four hours straight for a year and a half and reported no issues at all. The trade-off: the louvers can rattle at higher speeds, a minor noise for the extreme air movement it provides.
Raw power, real endurance: If you have a large greenhouse (up to roughly 20×50 feet) and want a low-maintenance thermostat, this fan outperforms everything else here on pure volume.
Reach for this if: you need heavy-duty air exchange for a large or commercial-sized greenhouse and want thermostat convenience.
Think twice if: your space is under 200 square feet — this much CFM would be overkill and create excessive drafts.
2. AC Infinity AIRLIFT T16 Shutter Exhaust Fan 16″
The brainy option that texts you when your greenhouse is cooking.
This is the fan for the data-obsessed grower. The AIRLIFT T16 connects to your WiFi, letting you control it and view climate data from your phone. You can set dynamic temperature and humidity triggers, create schedules, and the app will send you alarms and notifications. It pushes a healthy 2560 cfm from its 16-inch frame, and the EC motor (an ultra-efficient brushless DC motor) is built for quiet, variable-speed operation.
The build quality is a standout — it features steel shutters and aluminum blades, and it carries an IP-44 rating (meaning it is highly resistant to dust and splashing water). Owners mention it dramatically reduces attic and greenhouse temperatures, with one noting a drop from 135°F to 110°F. Another Florida owner appreciated being able to check on their garage temperature from out of state via the Bluetooth app. The trade-off? The noise level hits 70 dBA at full speed, which is noticeable, and the menu-based controls can take some getting used to.
Automation at your fingertips: For the gardener who wants remote access and programmable climate cycles, this is the most technologically complete kit here.
Best for: tech-savvy greenhouse owners who want to monitor and control their environment remotely via smartphone.
Look elsewhere if: you prefer simple, physical controls and do not need WiFi connectivity or advanced programming.
3. iLIVING 20″ Wall Mounted Shutter Exhaust Fan ILG8SF20V-ST
A 5000-square-foot punch that keeps your plants cool and your electric bill low.
This 20-inch iLIVING model is a workhorse for large spaces, covering up to 5000 square feet with 3368 cfm of airflow. It uses a variable speed controller and a thermostat with a range of 32°F to 130°F, giving you fine control over how much air is moving. Unlike the 24-inch model, this one steps down to a copper-wound motor rated at 2.2A, making it more manageable for standard 15-amp circuits.
It is built with an industrial-grade galvanized steel frame and aluminum shutters that resist rust. The noise level sits under 69 dB, and while some owners find that “super quiet,” others note the shutters vibrate and rattle at high speed. One greenhouse owner said it was an excellent purchase, arrived quickly, was very quiet, and moved air effectively. Another measured a peak draw of 253W and a noticeable temperature drop from 94°F to 83°F in 45 minutes. The recurring gripe is the shutter vibration during operation — treat the mounting surface well to minimize it.
Why It Stands Out
- Huge 3368 CFM airflow for large greenhouses
- Thermostat and variable speed for hands-off control
- Rust-proof aluminum shutters stand up to humidity
One Honest Caveat
- Reported shutter vibration at higher speeds
- Some owners find the noise level loud at full power
Best for: medium-to-large greenhouses where you want powerful, thermostat-controlled ventilation without paying for WiFi features.
skip it if: you are noise-sensitive and plan to run the fan at full speed near a quiet outdoor seating area.
4. Amico 12″ Shutter Exhaust Fan, 1282 CFM
Small frame, huge efficiency — cuts your power bill while it cuts the heat.
This 12-inch fan is the energy miser of the group. Its 25W DC motor draws a fraction of the power that AC motors use, and it still delivers a solid 1282 cfm — enough to refresh a space up to 1600 square feet. The 8-speed touchpad and thermostat control let you dial in the exact airflow you need. The claim of a 66% energy reduction over AC fans is backed by its whisper-low 50 dB noise output, making it night-and-day quieter than the bigger AC models.
It comes with a corrosion-resistant galvanized steel frame and automatic gravity louvers. Reviews praise how it moves “a tremendous amount of air” for a 12-inch unit and that it comes with a handy drilling template for easy wall installation. The thermostat control, however, draws mixed feedback. Some owners find the control unit “not very user friendly,” requiring a long press to set, otherwise the fan runs constantly. It is also a bit heavy for its size at over 14 pounds, so ensure your mounting surface is solid.
Efficient and quiet: Perfect for the small to mid-size greenhouse owner who wants modern DC motor efficiency and automatic temperature control on a budget.
Reach for this if: you want a low-power, low-noise fan that runs on a standard 120V plug and still moves plenty of air.
Think twice if: you hate fiddly digital controls — you might prefer a simple on/off fan or one with a remote and clearer interface.
5. addlon 16″ Shutter Exhaust Fan, 1700 CFM
Whisper-quiet airflow that won’t disturb your morning coffee by the greenhouse.
The addlon 16-inch stands out for its combination of low noise and advanced features. The 60W EC motor (another type of ultra-efficient brushless motor) pushes 1700 CFM at 1700 RPM while operating at a noise level of just 55 dB. That is a full 15 dB quieter than some of the 20-inch AC fans, which makes a huge difference in perceived loudness. You get a remote control with an LED display, 8 variable speeds, and a 1-8 hour timer for automatic shut-off.
It is built with a heavy-duty galvanized steel frame and rust-proof aluminum blades. The gravity shutters close tightly to block wind and bugs, though one owner noted some remaining gaps that smaller insects could exploit. Owners who installed it in chicken coops and smoke rooms praise its strong airflow and low energy draw. The installation can be tricky because the hole-cutting template may not perfectly match the unit, so measure twice before cutting.
What Wins People Over
- Very quiet at 55 dB with strong 1700 CFM airflow
- Remote control with timer and 8 speeds is very convenient
- EC motor is energy-efficient
A Few Notes
- Insect screen gap reported on some units when shutters close
- Installation template can be inaccurate
Perfect for: small-to-medium greenhouses near your home where noise is a concern and you want remote and timer control.
Not ideal if: you need to ventilate a large space over 2000 square feet — the 1700 CFM will be underpowered.
6. VENTISOL 20″ Shutter Exhaust Fan, 3500 CFM
Uncomplicated, rugged, and moves a staggering 3500 cubic feet of air per minute.
If you want maximum CFM for the lowest price and you do not need a thermostat, the VENTISOL 20-inch is the straightforward answer. It runs at 1309 RPM and produces 3500 CFM — the same raw power as the KEN BROWN model below — but it comes in a sturdy, all-metal, powder-coated black finish. The automatic gravity shutters seal when the fan is off, and the pre-installed 5.4-foot power cord means you can mount it and plug it in within five minutes.
Owners who installed it in chicken coops, attics, and man caves praise its ability to “significantly reduce temperature” and pull smoke out effectively. One buyer used two horizontally in their attic access to great effect. The feedback on quality is “price appropriate” — it is a simple, effective design without premium frills. A very occasional unit may arrive with a blade slightly out of alignment due to shipping, but the general consensus is that it is a durable, high-value fan.
Simple, raw power: Ideal for the buyer who needs high-volume air exchange, doesn’t want to program anything, and wants maximum value per CFM.
Best if: you have a large greenhouse or shed and just need a powerful, reliable on/off fan without extra features.
Look elsewhere if: you require automatic thermostat or humidity control to save energy and keep conditions stable.
7. KEN BROWN 20″ Shutter Exhaust Fan, 3500 CFM
Bare-bones cooling muscle that relies on metal, not menus.
The KEN BROWN 20-inch is the VENTISOL’s direct counterpart, delivering the same 3500 CFM from a 1309 RPM motor but with a brown metallic finish. It shares the same philosophy: big aluminum shutters, a pre-installed 5.4-foot cord, and no-brainer plug-and-play installation. This is the fan you choose when you want to cut a hole, mount it, plug it in, and forget it.
The AC Infinity AIRLIFT T16 is built with high-grade aluminum shutters and blades to resist corrosion in a damp greenhouse. Owners say it “cools down a home” and is “very quiet” compared to a swamp cooler. It draws a low 1-2 amps, so it costs less to run than centralized air conditioning. Note: the initial louvers may not close fully for the first few days (a small gap that resolves as they settle), and this fan is not an air conditioner replacement — it exchanges hot air for cooler outdoor air, so you need a fresh air intake on the opposite side of your greenhouse.
Why to Grab It
- Massive 3500 CFM at a competitive price
- Corrosion-resistant aluminum build for high humidity
- Installs in minutes with no wiring
One Thing to Know
- No thermostat or speed control — it runs full speed when plugged in
- Initial shutter alignment may need a few open/close cycles to settle
Best for: buyers who want a big, powerful, and durable fan with zero electronic complexity — just airflow.
Not for you if: you want to automate your greenhouse climate with temperature triggers or variable speeds.
8. HG Power 10″ Shutter Exhaust Fan, 647 CFM
The pocket-sized solution for tiny greenhouses and chicken coops.
If you have a small hobby greenhouse, a shed, or a chicken coop, the HG Power 10-inch is your budget-friendly entry point. It moves 647 cfm — enough to exchange the air in a small 4x4x4 space every minute or so. The design features a 12.6-inch powder-coated steel grille with automatic louvers that seal shut when off, keeping rain and dust out. It is designed for full interior installation, so you can mount it from inside without needing a ladder outside.
The motor runs at 1400 RPM and draws just 42W. Owners confirm it “works well in greenhouse, reduces humidity, quiet,” which is the exact headline for a small grow space. The full-metal build feels sturdy, and it comes with a detachable steel mesh bug screen. The downsides are that the power switch placement is awkward and some customers note the louvers stopped closing automatically after a week, requiring a manual push. For the price, it is a fantastic starter fan that solves humidity and heat in compact spaces.
Small space specialist: A perfect entry-level fan for tiny greenhouses, coops, or sheds where you need reliable, quiet air movement for a very low investment.
Reach for this if: your greenhouse is under 100 square feet and you want a simple, quiet, low-power solution.
Look elsewhere if: you need to cool a larger space or you require thermostat control — this is a basic on/off fan.
Understanding the Specs
CFM (Cubic Feet per Minute)
This is the single most important spec. It tells you how much air the fan pushes every minute. To cool your greenhouse effectively, you generally want the fan’s CFM to be roughly equal to the total cubic volume of your space (length x width x height). If your greenhouse is 10x10x8 feet, that is 800 cubic feet, so a 700-900 CFM fan will do the job. A larger 20x20x10 foot space needs around 4000 CFM.
DC, EC, and AC Motors
The motor technology affects noise, efficiency, and control. AC (alternating current) motors are traditional, cost less, and are very powerful, but they are louder and always run at full speed. DC (direct current) and EC (electronically commutated) motors are the newer, premium options — they use up to 66% less energy, run much quieter, and allow for variable speed control without losing efficiency.
FAQ
How do I calculate the CFM I need for my greenhouse?
Can I use an attic exhaust fan in my greenhouse?
Where should I mount the exhaust fan in my greenhouse?
How long does a greenhouse exhaust fan typically last?
Is a thermostat control necessary for a greenhouse fan?
Should I get a DC motor or an AC motor for my greenhouse fan?
My fan is loud. Is that normal for a shutter exhaust fan?
Can I install these fans myself without an electrician?
Final Thoughts: The Verdict
For the majority of shoppers, the exhaust fan for greenhouse winner is the iLIVING 24-inch ILG8SF24V-T because it delivers class-leading airflow with thermostat control and a proven durability record from hundreds of satisfied owners. If you want smart, remote control and WiFi monitoring, grab the AC Infinity AIRLIFT T16. And for a budget-friendly, ultra-efficient option for smaller greenhouses, the Amico 12-inch DC is the one to reach for.
How We Picked
We do not accept paid placement. Every pick is matched to a real buyer and a real use-case; we do not hands-on test units.
Sources & Methodology
Specifications: manufacturer listings and product documentation. Review insights: verified customer reviews, as of July 2026. Pricing: not shown on this page (it changes often); check the current price via the retailer link.
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