It’s not likely that anyone would want to spend time in an attic on a hot summer day unless it was finished and had some cooling supplied. When there is no air conditioning pumping refreshing cooled air in the space, and the hot summer sun is beating on the roof, the temperature in your attic can soar. This can also affect the performance of your air conditioning system in other parts of your home. But, if you install adequate ventilation, you can remove that built up heat and bring the attic temperature down to parity with the air outdoors. Let’s take a closer look at attic ventilation in more detail.
An Attic Filled with Heated Air
The air conditioning system in your home has to remove a great deal of heat when it gets hot outside. Every family member and pet in the home radiates a variable amount of heat, hot sunlight pours through windows, and even cooking in the kitchen releases heat. But, many people are unaware of the most significant source of heat in their home during summer, and that’s an unventilated attic. The heat builds up in the attic from the sunlight hitting the roof, and it has nowhere to go. Gradually the trapped hot air will begin to heat up the floor of the attic, and as a consequence the ceiling of the story below.
Why Unventilated Attics?
Given this information, a person may wonder why ventilation isn’t installed in attics as a matter of course. Well, unventilated attics are more common in buildings that have complicated roof assemblies where it would be difficult to create a sealed ceiling plane. Homes that date back to before air conditioning don’t have attics to deal with this technology. Unventilated attics are more common in coastal areas that are subject to high winds and severe storms. In these areas, wind driven rain could enter the attic via the fan assembly, and there could be pressurization issues.
Attic Ventilation Options
Unless you’re planning to convert the attic into a living space in the near future, it doesn’t makes sense to seal the space and route the air conditioning vents there. But, it is possible to install some attic fans which can continuously circulate the air replacing hot stagnant air with fresh outdoor air. This will set the attic temperature to same as outdoors and prevent that space from turning into a literal oven. Broadly speaking, there are two main types of attic fans to choose from; they are gable fans and rooftop fans.
Gable Fans: These are places across from each other at opposite ends of the attic (in the gables hence the name). One of the fans is configured to blow air in and the other to blow air out. Together they help to circulate fresh air into the attic and remove the head air.
Rooftop Fans: These fans are installed on the roof, and they perform two crucial tasks at the same time. First, they expel any stagnant heated air, and second, they bring cooler air into the attic space.
Both of these attic fan types are a popular option for homeowners installing solar power systems. The sunlight only hits the roof during the day, it’s the main source of heat in the attic, and so the attic fans are only really needed during the daylight hours. So if you have your fans powered by a solar panel they can start and stop automatically and you don’t need to remember to flip a switch each morning. This can all be achieved without adding to your power bills, making it a cost effective option. Once the fans are installed, they will work in the background and remove the heat, making your home easier to cool.
Attic Related Humidity Problems
Unventilated attics can store a large volume of trapped heat, but this isn’t the only problem. A heated attic space also traps moisture in the space from two key sources.
Natural humidity form outdoors.
Manmade humidity from indoor activities, such as: showering, boiling water and from other sources in the rooms on lower storeys.
This humidity makes its way into an unventilated attic, and it becomes trapped there with the heat. This creates near perfect growing conditions for mold and mildew that quickly become a cause for concern. Certain types of insulation materials used in your attic could even be destroyed by mold spores, and this is also a health risk. If you have any items stored in the attic, they can also be attacked by mold spores and damaged.
The Downside of Attic Fans
There is one major drawback that will affect how effective the attic fan will be. It’s essential to create a tight seal to separate your attic from your living spaces to achieve any kind of appreciable energy efficiency benefits. If the attic isn’t sealed, the air circulation created from the attic fans can suck the air conditioned air in your home into the attic and then outdoors. The air can be sucked into the attic through gaps or cracks in your ceilings or via an attic entry point. This would significantly decrease the value of the ceiling fans and you may end up wasting a large volume of treated air.
Getting the Attic Sealed Professionally
Before you get an attic fan installed, it’s a good idea to carry out a thorough inspection of the barrier between the attic and the rest of your home. This can be achieved by someone with good DIY skills, but it’s probably a better idea to hire a professional to carry out this detailed work. Every crack that could allow treated air to escape from your home must be sealed to prevent a loss of cooling efficiency.
If you’re interested in lowering your energy bills by installing attic fans and sealing your attic contact a local certified HVAC technician for expert help and advice. They will be able to provide you with a no obligation consultation for the necessary work.