Home design is much more complex than I ever realized. You can’t just throw up four walls, slap on a roof, and call it done. Homes need to breathe, and breathe correctly. Pressures, temperatures, conductivity, and other physics principles play a role in how it all works. Proper home designs turn homes into a system with features that work together to keep the home stable against the natural elements. If any one of these parts becomes out of whack, it throws off the whole system.

The attic is where most homes exhale the air they breathe in. Just as if you could not breathe, if the attic cannot exhale properly then it creates problems for the entire house. Attics should ventilate at least one square foot of roof ventilation for every 150-200 square feet of attic space. Air is ventilated out of the attic through soffit and roof vents.

While the more attic ventilation the better, more vents can upset the delicate balance here. I heard of one story where a homeowner tried to increase their ventilation rate by installing two different kinds of outlet vents. This resulted in transforming the weaker outlet vent into an inlet vent. Air simply short circuited between the vents, preventing soffits from drawing in air flow.

During the summer proper attic ventilation keeps your attic from collecting heat. Without ventilation, your attic can turn into a hot box and spill that unwanted heat back into the living area. This increases your energy bill since your air conditioner has to work that much harder. It also destroys your shingles.

During the winter months, mold can result from improper attic ventilation. Hot air rises from the furnace in the living area and coalesces against cold surfaces on the attic roof. Often these are places with nails since iron is a great temperature conductor. When a hot air mass meets a cold surface, the dew point is reached and water droplets begin to form. This moisture results in mold that will create health problems and eat away at your attic and roof.

The best tip I can give you is to inspect your soffit and roof vents on a regular basis. They can easily become blocked and disrupt system flow you have in your home. But this will not help you if your attic is improperly designed in the first place. Check with a reputable home design inspector to determine if this is a cause. An improperly ventilating attic will cost you in energy bills and mold damage.