Before we dig any deeper on how much does roof ventilation cost, let’s have a look at its importance. When a roof is built without air intake and exhaust vents, the sun’s heat can cause a buildup of warm air in the attic. This heat could radiate to other areas of a house, which could lead to unbearable indoor conditions during summer. On a typical day’s heat of 90°F, the temperature could rise to 140°F when there is poor airflow. In addition to heat, the existence of moisture in the attic could lead to serious problems in the future if proper venting is not installed.
Shingles and roof decking could suffer and prematurely deteriorate. Radiating heat could also mean air conditioning units and other cooling units need to work harder to keep the temperature down, ultimately increasing the electricity bill.
Uncovering how vents work
There are benefits to having a fully functioning ventilation system for the entire year. Roof vents work by allowing air to freely move from one point of the roof to another. This ensures that no moisture and heat is transferred out of the roof, keeping the house cool. These systems typically have several components systematically placed for optimal function. This air movement can be achieved in two different ways: mechanical and natural. Natural air movement is driven by either stack or wind effect. Meanwhile, mechanical vent systems utilize electrical motors.
Mechanical systems are the most effective. A powered system can effectively transfer hot out and cold air in. However, there are a few tradeoffs to this kind of venting solution. First, some fans require more than 100W of electricity to run. This could increase your electricity bill significantly. Installation is also more complicated, and in most cases, may require professional help. There are also solar-powered fans that allow off-grid operation but are a little bit costly.
How much roof ventilation do I need?
Having enough airflow in your attic definitely, keeps the electricity bills down during summer. Expelling hot air not only keeps the entire house cool, but it also protects the roof structure from moisture-caused damage. However, most homeowners are oblivious about how much airflow they need in their home. It is best to know how much you actually need. This is to ensure that you would have enough airflow to keep the temperature in your attic relatively tolerable.
It’s relatively easy to know just how much ventilation you need for your attic. Generally, you would need 1 vent area (around 1 square foot in size) for every 150 square feet. Assuming that your attic has around 450 square feet of space, you would need to install at least 3 roof vents.
The recommended allocation of vents is at 60% and 40%. The 60% vents would be located in the soffit area and in as cited in the example above, there should be 2 soffit vents installed. The other 40% is for a ridge vent. The type of ventilation may depend on the climate as well as your preferences. If you are still undecided, you should consult a professional to get a second opinion.