Understanding the basics of roof ventilation can prevent expensive repairs later. Learn about how to achieve optimal airflow for your home.

Q: Even though we have done a good deal of work to increase energy efficiency in our 1960 split-level home in San Carlos, we are having a difficult time keeping the warm air inside the house ...

Instead, gable vents are at each end of the house. The intakes are soffit vents. This seems to have worked fine with our current roofing, three-tab asphalt shingles with felt underlayment.

The vent area should be divided equally between soffit and roof (or gable) vents. Thus, in the 2,500 square-foot attic noted above, at least 8.3 square feet should be allocated to soffit vents ...

Soffit and fascia are two essential components of any roofing system, helping to provide ventilation and weather protection. Soffit is the underside of the eaves extending from the roof overhang.

How much soffit ventilation should I have? What is the best way to cool my attic naturally without electric-powered fans? A: I applaud you for trying to ventilate your attic the old-fashioned way.

The original design had no soffit vents and only a ridge vent at the top. The new roof still has no soffit vents, but several roof vents that stick up above the roof at the bottom and top of the roof.