Build with Mark - Ridgevent gives you 3 times the amount of Ventilation.

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	© Mark Saville 2006	Roof vents and ridge vent
			Venting of your attic space is one of the most important systems in your house and really there is no such thing as over-venting an attic space. The temperature in your attic should be the same as the outside air in any season to guard against condensation buildup which can eventually lead to wet insulation and truss/roofdeck rotting.The general rule is 1 square foot of vent area for every three hundred square feet of attic area but more is better. Attic venting will not lower the temperature of your house in winter.
	Ridge venting will give you the most vent area possible when used on a gable roof but your ridge line may not be long enough in other types such as a hip roof. In that case the square type vents will have to do but make sure there is enough of them to get acheive the 1/300 rule The image to the left is an example of a nail-through type ridge vent that allows you to install the shingle caps right over the vent making a very neat looking roof. You can also gain a lot of vent area with a continuous ridge vent as opposed to the square type vinyl vents. You just cut the roof sheeting 1 1/2" away from the ridge on each side creating the opening for the air to get out.

The photo to the right shows the finished ridge with the caps installed creating a very nice looking roof with lots of ventilation.The caps are nailed right over the vent material with 2 1/2" roofing nails which go through the vent material and into the roof sheathing.

The shingles are installed over the vent to match the roof.

In order for roof venting to work we need to have the cooler dry air enter through soffit vents pushing the warmer moist air out through the roof venting. The area of the soffit venting should be equal to the area of roof venting so that the system can work properly. In any case the roof vents should be the first concern and provide enough open area to fully vent the attic space.

Roof vents and ridge vent