Solar attic fans are a great investment that can provide many benefits to your home. Ventilation from these fans improves indoor comfort and keeps electricity costs lower. The fans can help to protect your roof and allow it to last longer. In this article, we’ll explain the importance of proper attic ventilation and show you why solar attic fans are one of the best options for ensuring your attic is properly ventilated.
The Link Between Proper Attic Ventilation and Electricity Costs
Having sufficient ventilation in your attic makes a major difference in how hot your house gets during the summer, which in turn affects how much your air conditioning runs and how much electricity it uses. On hot summer days, it’s not uncommon for the temperature in a poorly ventilated attic to climb above 100 degrees in the afternoon.
As hot air rises into an uninsulated attic, much of the hot air radiates into your living spaces, causing the temperature throughout the house to increase. This is why your air conditioning systems often still need to run occasionally throughout the evening even after the temperature outside has cooled down quite a bit.
Without adequate ventilation, an attic can also get extremely humid due to moisture from inside the house. This creates the potential for mold issues. Even if mold doesn’t start growing, you can end up with damp insulation in the attic. If the attic loses insulating value, it allows even more heat to flow into your home on warm summer days.
By ensuring that your attic has sufficient ventilation, you can keep your home quite a bit cooler during the summer. That means your electricity bills will be lower since your air conditioning won’t have to do nearly as much work. Some studies have even shown that adding ventilation to a poorly ventilated attic can reduce how much electricity the home’s AC system uses by up to 30%. This reduces wear and tear, which extends the lifespan of costly HVAC systems.
Passive vs. Active Attic Ventilation
Virtually all attics have at least a few vents in the gable ends, soffit panels or on the roof ridge or slopes. This is because the building codes in most areas require attic ventilation, and this requirement has been in place since 1948. The only exception to this requirement is if the attic has been converted into a living space and is considered a conditioned part of the home.
Passive ventilation works fairly well on windy days since the wind helps to blow more air through the vents. It works even where there is no wind since the hot air that rises and flows out of the upper vents causes slightly cooler air to get pulled in through the lower vents. However, passive ventilation is rarely sufficient on its own since air doesn’t flow out fast enough to keep the attic from being hotter than the temperature outside. Ideally, you want to ensure that your attic is never more than 10-15 degrees hotter than the temperature outside.
Solar attic fans provide active ventilation since they continuously run throughout the day and draw all of the hot air outside. This then creates a strong draft that pulls air in from outside through the other vents so that the attic always stays close to the outdoor temperature during the day and early evening. By the time the sun goes down and the fans shut off, the attic will be sufficiently cool and the passive vents then ensure it stays at whatever temperature it is outside. Some solar fans are hybrid and can run on both electricity and sunlight.
There are also other types of attic fans wired to the home’s electrical system and programmed to run on a timer or with a thermostat. These vents can also help to keep your home cooler and lessen the workload on your air conditioning. However, they won’t have as big of an impact on your energy bills as solar attic fans. As long as the sun is shining, solar attic fans will run continuously throughout most of the day without using any electricity.
How Solar Attic Fans Can Also Help Protect Your Roof
As long as there isn’t enough snow on your roof to cover the solar panels on your attic fans, they will also run throughout the winter. Ventilation is just as important during the winter as it is during the summer. Even if your attic floor is properly insulated, some of the hot air produced by your heating system will rise through the floor into the attic. The result is that your attic ends up being hotter than the air outside if it doesn’t have constant ventilation. This can lead to ice dams forming on the roof, which can cause major damage to your shingles and gutters and increase the chances of roof leaks and the costly damage that they can cause.
If the attic is warmer than the air outside, it causes the roof deck to be fairly warm. Whenever there is snow on the roof, the snow directly sitting on the roof will melt faster than the layer above it. The snowmelt then flows down the roof slope and then often ends up refreezing once it reaches the eaves. This can then create a thick layer of ice that prevents water from draining off the roof into the gutters. As a result, you can end up with water getting trapped and potentially starting to soak into the roof. The ice can also start lifting some of the shingles and allow water to seep underneath them.
Although solar attic fans obviously won’t provide any ventilation at night, they will still make a big difference in how hot your attic gets during the winter. That means you’ll have less chance of ice dams forming and potentially damaging your roof.
In addition to preventing ice dams, solar attic fans also help to protect your roof during the summer. Extreme heat always causes shingles to deteriorate and weather more quickly. That means by keeping your attic and roof cooler, the fans can help extend the life of your roof by slowing down the rate at which the shingles deteriorate. Another way they can protect your roof is by decreasing the humidity in your attic. If your attic is too humid, you can often end up with the roof trusses and roof sheets warping, cracking or starting to rot. Attic fans help to prevent these issues by ensuring your roof stays much cooler and much less humid throughout the year.
If you need any electrical, plumbing, heating, air conditioning, or indoor air quality solutions the experts at Magic Electric, Plumbing, Heating + Air are here to help. Our team has years of experience providing exceptional home services and can professionally take care of all of your needs. We have locations in Jerome, Twin Falls and Boise and we serve customers throughout the Magic Valley and Treasure Valley areas. Give us a call today for more information or to schedule a service appointment.
