ridge vent or power let the debate insue

[hoppyih]

here's the picke i have, living in arizona, the folks down here are very confused in ventilating systems. All of the new homes you see have a few soffit vents and two gabble vets, oh an two or three of the static vents on the roof.
I'm looking at putting up either a ridge vent or a solar power vent. I'm looking at really cooling the attic space, the brilliant folks down here put there air handlers in the attic :confused: .
Yah bugs me too not having a basement :mad:
Any thoughts on this one would be fantastic.
H

[deejoe]

First of all, are you referring to ventilation to an attic area that is above a living area of the home?
In other words, is this area "unoccupied", other than for some bits of stored junk,etc
For this type of uninhabited attic, all that is required to make it expel any extreme heat (shingle damage) is to properly vent it by way of SOFFIT vents, together with either a continuous RIDGE vent or a sufficient number of individual vents placed as high up and as near to the peak as possible.
This enables a "gravity air-flow into the soffits and causing any heat build-up to just rise and go out the high vents.
No power fans are needed for this type of venting to do the trick.
Hot sun heat build-up during the day can make an attic area very warm, but usually during the night this air will be replaced by cooler air coming in.

As long as the attic floor (ceiling of the area below) has an ample R value insulation (R28 or greater) the heat in the attic will not have much (if any) infiltration effect on the liveable areas below.
Also, the amount of VENT AREA has a lot to do with this working properly.
The ratio of venting is a MINIMUM of 1 sq. ft. of ventilation for every 300 sq ft of attic floor area. This amount is divided equally between soffit and ridge vents. (calculated free area)
Note the word MINIMUM,you can NEVER over vent an attic area as long as an sufficient insulation R factor is installed in the attics floor.

[WFO]

Avoid asphalt shingles (especially dark ones) and go with something reflective. Look into radiant barriers.

....oh yeah, ridge vents over power. Bigger the better.

[CR500]

There was an article in the washington post the other day where the writer was saying that he didn't like power vents because they tend to pull air out of the house. Seems to me that if you have enough open area for the air to enter the attic, that should not happen.

My house has a hideous Mansard type roof. There are NO soffit vents because the soffits are at first floor ceiling height. Venting them would allow air to circulate in the 2nd floor walls. I have a power vent in the attic and a bunch of passive air inlets on the roof. I think I set the vent to 110 deg and it runs all day during the summer.

The roof is old and seems to have held up well. Next year I'm installing a new roof and will see if there is any way to install a ridge vent (I think my roof has a small section of ridge) while also leaving all the passive vents and power vent.