Attic Fan vs. Whole House Fan

On those hot, humid days, it can feel like there’s nothing more refreshing than cracking open the windows and letting the breeze blow through the house. But sometimes, the temperature outside is just too hot for that. You need something that can cool off your home without being expensive or energy-sucking.

A roof or gable-mount attic fan removes hot air from the attic and replaces it with cool air from the outside. Meanwhile, whole-house fans are in the ceiling, and they discharge hot air from the house into the atmosphere through exhaust ports and vents.

Before choosing, consider your home’s climate, size, layout, and budget. This article will discuss the distinctions between the two types of fans.

Are Attic Fans the Same As Whole House Fans?

Attic fans and whole-house fans perform similar functions but target different parts of the house. These ventilation fans operate differently, cost differently, and proper installation is necessary to keep them running effectively.

As the name suggests, these are two systems with a similar mission of cooling the house and maybe lowering energy costs. Nonetheless, the most noticeable difference is how they accomplish the intended goal.

Before you pick the one that works best for you, let’s look at the pros and cons of both.

Read: How To Keep House Ventilated In Winter? (10 Tips)

How an Attic Fan Cools the House?

During the hot season, the attic will get warmer than the outdoors. Warm air there circulates and spreads heat downwards to the rest of the house. This heat level might be uncomfortable or even unbearable for the occupants. Therefore to reduce the heat in the rest of the house, the attic has to be cool.

Cooling your home with an attic fan may be more affordable than installing an air conditioner. 

Now let’s see how an attic fan cools your house.

As we’ve already seen, using an attic fan is one of the ways to keep your home cool in the hot season. Instead of concentrating on the entire house, the fan mainly cools the attic and, in turn, cools the lower rooms of the house. They draw hot air down from the attic and push it out through the soffit vents on the roof’s underside.

The attic fan is an integral part of a home’s ventilation system. They’re effective because they ventilate the roof space, which is the area where most of the heat in your house gets trapped.

When the attic hits a specific preset temperature, the fan kicks on, and the blades create a wind current that pulls air up through the attic space and out through the exhaust vent. The system creates a vacuum effect, forcing the hot air from the attic to exit the building as cool air enters the space.

Usually, you install attic fans in conjunction with soffit vents and gable vents that ventilate other parts of the enclosed attic space. They also reduce humidity levels inside your home by helping to dry out any damp or humid areas in your attic.

Pros

  • Not complicated to install. It requires less time to install because the main focus is the attic.
  • Suitable for hot weather. Since the purpose is to remove hot air from your attic, you can use it in any climate.
  • Cools the attic. Keeps attic cool in summer and dry in winter
  • Helps prevent mold and mildew. By moving dry air from the outside into your attic, moisture that might accumulate is dried out, preventing mold and rot.
  • Less expensive to install. Compared to a whole house fan, the overall cost is less.
  • Lowers heat in the attic. This is because the design is specifically to cool the attic
  • Reduce roof wear and tear. Prevent fast aging of asphalt roof by preventing warping of shingles 

Cons

  • Carbon backdraft. If you have appliances in the house running on gas, the negative pressure can cause carbon monoxide to filter back into the house
  • Can increase energy consumption. An attic fan will often be on for proper ventilation, hence consuming more power.
  • Resale Value. Attic fans don’t add any meaningful resale value to the property

Read: Why Is House Thermostat Reading The Wrong Temperature?

How a Whole House Fan Cools the House?

A whole house fan is set up to run when the air outside is cooler than the air within the home itself. 

Generally, the contractor will mount the fan above a central hallway’s ceiling on the attic floor.

Here’s how it works. When the temperature outside hits between 70 and 80 degrees Fahrenheit (21.11-26.67 °C), the fan will turn on. It brings cool air in through the open windows, sucking hot air up to the attic and eventually out. Thus, you don’t have to use your air conditioner or other cooling methods as often, which helps reduce the cost of running your HVAC system.

Even though it depends on the house plan and the climate, a good whole house fan should be able to provide 3 to 6 air changes per hour.

To get started, find a place in the attic where you can install the fan. It should be near an outside wall for easy access later on. Then, connect the wiring from the attic down through the walls and into your main living space so you can plug it in when you need it.

For the fan to function correctly, the windows down on the lower floors have to be open to allow in cool air from outside.

Pros

  • Energy-efficient. A perfect alternative to an AC unit. They use less than 15% of the energy used by an AC system.
  • Works well with house plans. Draws cool air in through open windows, which are naturally part of a typical house.
  • Can cool a house fast. A well-installed fan should be able to cool the house within an hour or less significantly.
  • The resale value of a house. The presence of a whole house fan will increase the value of a house

Cons

  • Not suitable in high humidity areas. It will only work well in a cool climate
  • Costs. Installing a whole-house fan can range from $950 to $2750
  • Installation is complicated. Since this involves the whole house, a lot goes into it.
  • Noise. If the installation is incorrect, you’ll end up with a noisy system

Read: How To Keep Low Humidity In The House?

How To Pick the Best Fan for Your Home?

Now that we’ve seen both Attic fan and whole house fan, you’ll have a better idea about the best house fan for your home. Attic fans and whole-house fans are both great ways to keep your home cool when the temperatures are high, but each has its benefits and drawbacks.

Therefore, before making a decision, consider the problem you’re facing and the result you want to achieve.

An attic fan is a good choice if:

  • If you are dealing with a modest budget
  • Your home is in an area where the weather is warm and humid
  • You already have an air conditioner that runs regularly, and you want to find a cost-effective way to keep your home cool

A whole house fan is a good choice if:

  • You’re hoping to maximize energy savings
  • You want to get the best return on resale value
  • Your house is in a cool area
  • There is no air conditioning unit in your house

Hopefully, this article has provided you with the information to distinguish between attic fans and whole-house fans. You can use them in conjunction with air conditioning: each with its own unique advantages. 

Consult an HVAC professional before deciding which type of fan will work best for your home in case of any doubts.

Read: Why Mini Split Fan Runs Continuously?

Attic Fan, Whole House Fan, and Air Condition: A Comparison

An attic fan can effectively complement air conditioners as they combine to maintain a comfortable temperature in your house. However, a whole house fan will be as good as an air conditioner in maintaining the appropriate temperature in the proper climatic condition. Regardless of the weather, an air conditioner will always keep your home at a pleasant temperature. 

Read: Can A Mini Split Cool A Whole House?

Conclusion 

When your choices are a whole house fan and an attic fan, it’s essential to consider the conditions you will be using them. Both attic fans and whole-house fans have different types of operation, but they all achieve the same result. Ultimately, either type of fan can help keep a home cool.

An attic fan may be the best option if you aim to keep your home cool without breaking the bank, although it depends on where you live. If you want to save on energy while cooling the whole house, the answer is a whole house fan.