All About Roof Ventilation

It is the only thing between you and the hot sun or the cold rain and snow.  It can also cost you thousands of dollars to repair or replace.  Your roof takes a beating no matter what the weather and this is why having a properly installed roof ventilation system is so important.  With it, you and your family can live comfortably in all seasons (not to mention saving money on energy bills).  Without it, you might become a contractor's best friend.

All things being equal

Vents let air circulate through you attic or crawl space.  Your everyday activities produce heat and moisture (see that steam coming out of your dishwasher or covering your bathroom mirror?) that could otherwise be trapped, causing wood to rot and warp.  This moisture can also build up in your insulation, diminishing its effect and costing you money. 
 During the dry summer, the heat of the air and sun can cause beams and other roofing materials to dry and crack.  The built-up heat in your attic will also force your air conditioner to jump into overdrive just to keep your living space tolerable. 
 To avoid either of these from happening, the air inside your attic needs to be as close as possible to the air outside.  It is a delicate balance, but you can do it with the necessary know-how.

Keeping current(s)

Your basic roof ventilation system has two parts: soffit vents, which let air into your attic or crawl space, and ridge vents, which let it out.  The placement of these is essential.  Soffit vents are found at the low edge of your roof, under or behind your gutters.  Ridge vents, as the name suggests, run along the ridge of your roof.  Through the natural current (or convection) of the air, cooler air comes in through the low placed soffit vents and pushes the hot air out the ridge vents.  Wind blowing across the top of your roof also causes a vacuum effect which sucks air in through the lower vents. 

For large attic areas, you may want to consider installing a turbine vent.  Turbine vents are small (an average home-use model is about twelve inches in diameter), round metal instruments that does the same job as ridge vent, only with a little more oomph.  As the vanes (similar in action to the blades of a fan) are spun by the wind, the warm air inside your attic is pulled out.  They are a low cost, low maintenance, and (usually) silent way to get the air moving.

If this is still not doing the job for you, another option is a power attic ventilator. Many of these products come equipped with a thermostat so that it turns on when the attic temperature reaches a certain preset point, and a humidistat, which monitors the humidity in the space.  Some of the newer models even come solar-powered, so that it does not cost you money while it saves you money.

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