Condensation can wreak havoc on your household if you don’t correct the problem early on. An improperly insulated attic is a prime candidate for the formation of condensation, which can lead to mold and mildew, damaging the interior structure of your home. To prevent condensation, ensure your attic is properly ventilated. Inadequate ventilation can damage your roof, and the decking, encourage ice dams and shorten your roof’s overall lifespan by half. We’ll break down how to properly ventilate, but first a little science on condensation.
An Explanation of Condensation:
Air is all around us. And it contains water vapor. The temperature of the air determines exactly how much moisture it can hold. The warmer the air is, the more moisture it can support. When warm air comes into contact with a cold surface or cooler air, it loses its ability to hold water vapor, and it turns back into water. This process is called condensation. Now, because air is all around us, where the air releases its water can be quite problematic.
Three types of Condensation: Condensation can be grouped into three common types.
Cold-bridge condensation– When warm, humid air collides with cold surfaces or cooler air, condensation will occur. Because warm air rises, condensation often takes place at the base of walls, on windows and at the bottom of your roof.
Warm-front condensation– In the winter, when a system of warm air passes through and enters a cool house, this humid air can turn into condensation.
Interstitial condensation– When a vapor-permeable material like insulation has moist air enter it, if the material is warm on one side and cool on the other, condensation can occur and dampen the material.
V is for Ventilation:
While condensation can lead to mold growth and issues throughout the household, your attic and roof are easily the most vulnerable. Proper insulation and extractor fans are all well and good, but to really protect your home from condensation, ventilation is key. There are quite a few options when it comes to purchasing vents. Vents come in many shapes and sizes depending on your individual needs. To put a proper ventilation system in place, you’re going to need both intake vents and exhaust vents to get air flowing naturally in and out of your roof cavity or attic. This prevents humid air from getting stuck and condensation from occurring.
The best vents for the job are a combination of soffit vents under the eaves of your roof cavity or attic and ridge or gable vents toward the top of the roof. Fresh, outdoor air will enter through the soffit vents and leave through the ridge or gable vents. NOTE: Every 150 square feet of space in your roof or attic should have a minimum of one square foot of ventilation.
To prevent roof damage and the need for roof repair, ventilate your home early on. But if you do find yourself in need of inspection or a contractor, feel free to reach us at 703-230-ROOF (7663) or online here. Remember, a dry home is a happy home.
