If you are searching the web for answers on how to properly ventilate an asphalt roof you have already discovered that there is no definitive answer. There are several things that go into the equation when calculating roof ventilation. What you have probably read is the importance of roof ventilation. In the summer months ventilation will reduce excessive heat and humidity build-up. In the winter months, ventilation will reduce condensation and prevent ice dams.
A roofing expert will have to determine total attic square footage, slope of your roof, venting requirement, and what type of product will be the best fit for your particular home. A roofing expert has to keep in mind what type of climate your home is in to properly ventilate your asphalt roof. In humid climates too much air intake can create moisture problems in your attic. In dry climates too little air intake can have the opposite effect. So what can happen if your roof has inadequate ventilation?
- Wood member rotting
- Formation of ice dams in winter months
- Buckling of roofing shingles
- Moisture accumulation in roof deck
- Shortened life cycle of roof
Did you know that attic ventilation is required by the Uniform Building Code, International Building Code, Standard Building Code and the BOCA National Building Code? Unfortunately for homeowners there is not one application that can be used for all asphalt roofing systems or fiberglass shingle roofing. So how do you ventilate your roof?
Asphalt Roof Ventilation Equation
For most residential roofs the standard for home builders and roofing contractors is a ratio of 1 sq/ft of ventilation for every 300 sq/ft of flat attic area. The caveat is that there has to be equal air intake and air exhaust. Your common sense may be telling you to put additional insulation under the roof sheathing or between the rafters of your roof.
Doing so can cause moisture and lead to damage to both the sub-roofing as well as your shingles. Excess insulation can also lead to increased temperatures in your attic and your roof shingles. Roof temperatures can decrease the longevity of your roof.
Benefits of Roof Ventilation
- Maximizes roofs longevity
- Prevents condensation
- Prevents ice-dams
- Reduces heating and cooling costs
Quick Ventilation Fixes
If you do not have an air intake or an exhaust ventilation system you will probably need to install a continuous soffit intake and ridge line outlet vent. If you have only soffit vents only you will probably need to install continuous ridge venting. If you only have ridge vents you will probably need to install continuous soffit vents at the eaves. If you only have gable vents you may need to add a continuous soffit intake along with ridge outlet vents. If you have any questions or would like to learn more contact our shingle roofing experts now.
For more information on Asphalt Shingle Roofing or to set up a free in-home estimate call Global Home Improvement at 888-234-2929 or visit online.
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