4 Best Solar Attic Fans On Costco

You might look forward to the warm temperatures and sunny weather of summer, but I bet you don’t look forward to the costs of keeping your home cool and comfortable. Every year, my aircon bill goes up.

So I decided to do something about it. I discovered that keeping my attic cool was a great way to control temperatures in my home without relying so much on air-conditioning.

I installed some solar attic fans, and since then, I haven’t looked back. Here’s how it all works. If you don’t ventilate your attic, it can heat up to over 120° Fahrenheit during the hottest hours of the day. This pocket of hot attic air transfers heat through your ceiling into your home, which means your aircon has to work harder and use more costly energy to keep things cool.

Why install solar attic fans?

A solar attic fan is a clever and economical way to cool down your home.

A solar attic fan uses a solar panel on your roof to generate electricity and power an electric fan that vents out the hot air in your attic, allowing cooler air to flow back in its place. This cools the attic and is an effective way to control the temperature in your home.

I’ve been so impressed with the solar attic fans that I want to help you enjoy the benefits of attic fan cooling too. I will give you a guide to buying attic fans, describing the different types and models out there and the things you should look out for. Then, when you know what kind of solar attic fan will suit your needs best, I’ll take you through the 4 best solar attic fans on Costco, reviewing them and looking at the pros and cons of each model.


How many and what size solar attic fans do I need?

It’s important to work out how many solar fans you need and what power output you need from them before you start shopping. Here’s how you do that.

What area is your roof?

You can work out the area of your roof space by multiplying your home’s width by its length.

What is the pitch of your roof?

Do you know the slope angle of your roof? The pitch is measured in twelfths. A shallow roof might have a pitch of 2/12, and a steeper one might be 8/12. The first number is the rise, and the second number is the run. The first number is the height, and the second number is the width.

Once you know your roof area and pitch then just work out how many fans you need using the tables below.

Guide for roofs with a low slope

Attic Slope Attic Size Attic Fan Size in Watts
1/12 – 4/12 800 ft² 1 Solar Attic Fan
1/12 – 4/12 1,200 ft² 1 Solar Attic Fan
1/12 – 4/12 1,600 ft² 2 Solar Attic Fans
1/12 – 4/12 2,000 ft² 2 Solar Attic Fans
1/12 – 4/12 2,400 ft² 3 Solar Attic Fans


Guide for roofs with medium slope

Attic Slope Attic Size Attic Fan Size in Watts
5/12 – 8/12 800 ft² 1 Solar Attic Fan
5/12 – 8/12 1,200 ft² 2 Solar Attic Fans
5/12 – 8/12 1,600 ft² 2 Solar Attic Fans
5/12 – 8/12 2,000 ft² 3 Solar Attic Fans
5/12 – 8/12 2,400 ft² 4 Solar Attic Fans

Guide for roofs with a high slope

Attic Slope Attic Size Attic Fan Size in Watts
9/12 – 12/12 800 ft² 2 Solar Attic Fans
9/12 – 12/12 1,200 ft² 2 Solar Attic Fans
9/12 – 12/12 1,600 ft² 3 Solar Attic Fans
9/12 – 12/12 2,000 ft² 4 Solar Attic Fans
9/12 – 12/12 2,400 ft² 5 Solar Attic Fans

Note that these numbers are guidelines based on 20W fans in regular attic conditions.


The 4 Best Solar Attic Fans On Costco

Now that I’ve given you some background on the benefits of solar loft fans, let’s take a look at the best solar attic fans you can find at Costco.

1. Remington Solar 30-watt Steel Solar Attic Fan


This is a powerful thirty-watt attic fan at a great price. I like the design which looks rugged but stylish too. I’d be happy to see this on my roof. The ability to angle the solar panel to 45° is a cool feature, too, since it means you can face the panel southwards to get the maximum sunlight exposure.

The fan comes with some handy features like the thermostat and humidistats, which are preset to switch the fan on at either 75% humidity or 80°F. This means you can just install the unit and leave it to get on with its job. It’s rated for 1550 CFM (cubic feet per minute), which offers excellent air movement under direct sunlight.

I like the fact that this is an American design product built specifically for Costco. The lifetime parts warranty also gives me confidence that I’ll get a lot of use, which is always important with solar products.

Key Features

  • Humidistat (on at 75% relative humidity) and thermostat (on at 80 degrees) pre-installed in each fan
  • Polycrystalline solar panel with brushless 24-38 Volt variable DC motor
  • Sleek weather-resistant design
  • Powder-coated steel housing with steel mesh and poly-vinyl blades
  • Lifetime manufacturer’s warranty on parts
  • Up to 1,550 CFM for up to 2,500 sq./ft. attics
  • The solar panel is adjustable up to 45° to optimize the sun angle


1 – The brushless motor is quiet and very efficient

2 – The built-in thermostat and humidistats ensure that the fan comes on when it’s needed

3 – The tiltable solar panel means that  this unit can be angled for maximum sunlight


1 –The 2,500 square-foot rating is accurate according to the chart above. This fan should be adequate for up to 2,500 ft² of attic space.


2. US Sunlight 25 watt Solar Attic Fan


This Product is a sturdy, no-nonsense galvanized steel solar attic fan. The fan has a small footprint since the solar panel mounts directly on top of the dome. Again the fan is fully automatic so I can just install it and leave it to do its thing, confident in the knowledge it will cool down my loft space.

The manufacturer suggests that this model can cool a 2600 square-foot loft space, but I think that might be pushing it a little. I’d be tempted to install a second low wattage fan just to help make sure my loft is well cooled.

Key Features

  • twenty-year limited warranty on panel and fan housing, five-year limited warranty on the fan motor
  • wind, hail, impact and corrosion resistant
  • low profile, rust-resistant, galvanized steel dome and base
  • solar panel mounts directly onto the dome
  • Up to 1820 CFM for up to 2600 sq./ft. attics
  • The solar panel is adjustable to maximize sun exposure


1 – Excellent performance for a twenty-five-watt model

2 – Thermostats and humidistats control the fan automatically so you don’t need a remote control unit

3 – Comprehensive warranties available


1 – A little more expensive than other models with similar specs.


3. Broan 28 watt Solar-Powered Attic Fan


Key Features

This is an attractive solar fan with a brown design that will go well with my roof tiles. The solar panel is flush with the top of the vent and this means that it’s an elegant-looking product. The drawback, of course, is that you’ll need to place it on a south-facing roof to maximize power input since you can’t change the angle of tilt of the solar panel.

The screen is made from corrosion-resistant aluminum., but the product is very well priced. Unfortunately, a thermostat comes only as an optional add-on and there is no humidistat either. To sum up, this is an affordable product with fewer features than the competition, but a more attractive design.


1 – This is a robust solar fan offering 28 W at an excellent price

2 – Attractive design with a small footprint, perfect for south-facing roofs

3 – Very simple to install


1 – The product is rated at only 537 cubic feet per minute, which is quite a bit less than the competition


4. US Sunlight 25W Solar Gable Fan


This is a light and easy-to-install solar fan specially designed for roof gables. The product comes packed with features and has an impressive 1,820 cubic feet per minute output for a twenty-five-watt panel.

It’s great that you can install the solar panel a distance away from the fan itself since this lets you place it somewhere that gets plenty of exposure to sunlight, giving your fan more power.

I would recommend this model for anybody who doesn’t have the option to install a combined fan and panel on a south-facing roof. After all, your solar roof fan is only as powerful as the amount of sunlight it receives, so panel placement is one of the most critical influences on performance.

Key Features

  • 1820 cubic feet per minute
  • 14 pounds weight
  • Fan and solar panel can be installed separately
  • 24 V motor


1 – You can install the solar panel up to 90 feet away from the fan, although only 30 feet of cable included. This allows perfect positioning for maximum power output.

2 – The thermostat and humidistat allow the fan to use heat in summer and reduce moisture in winter

3 – Automatic monitoring means that this is a plug and play device that you can leave to get on with the job


1 – There are cheaper products on the market, although this has high specs and offers good value for money.

If you have any comments or questions about this review of the four best solar attic fans on Costco, then please share them with us.

Leave a Comment