Passive turbine or power roof venting

[echotrail]

I seem to lack proper air movement in the attic space of our home. We have the standard passive roof vents as found on most homes and the soffit vents are unclogged. We live in a low area between hills and quite often the natural air movement is very calm or none when actually it's quite breezy at the top of the hills. Last summer I put a thermomitor in the attic and it got up to 126 degrees which seems high. I'm looking for opinions on using passive (non-powered) turbine style roof vents or power roof vents or even a solar power roof vent to help move more air. Chime in with what works for you. Thanks.

[BobT]

I'm not sure 126 is all that high with the sun shining. Attic venting uses the natural convection of air to allow warm air out the top by allowing cooler air in from the bottom. I don't think wind plays that much of a role. Maybe it does with certain ventilation designs though.

[Surface Tension]

Sometimes wind can goof natural convection so being in a hole is not any concern as far as venting goes. 126 degrees, where was the thermometer situated? I can sit in a tent with the windows wide open and it will get that hot.

If you have the proper amount of vents per sq ft and you don't have ice dams your part way there. How is the insulation. Your about 50 degrees above comfort level in summer. Winter that level will be 100 degrees below comfort level. So 126 degrees isn't that hot when you look at it. Again the insulation is the key element here. Could you cool the attic more? Yes, but is it necessary to do so.

[chad austin]

Echo

There are a few things to consider when replacing current venting. If you currently have static vents on your home, replacing only one or two of them with powered vents will not work as the powered vents will cause reverse flow from the non-powered vents and there will be little to no movement at the soffit vents, all of the air will be exchanging at the top 1/3 level of your roof. As far as replacing them with turbine vents, I have found that many roofs that I have looked at in the winter with turbines have snow in the attic from blowing winds and that snow will melt in the spring introducing the insulation to moisture thus diminishing the R-value.

Another thing to consider is your family's health, an attic is the perfect place for mold to grow and live as the conditions can be perfect if the moisture levels get above 1-2%.

You had stated that your attic temp was 126 F, where a properly vented attic should be around 105 F. The minimal cost to fix your venting issues will save you money in the long run as heat does not follow gravity but rather goes to areas that are coooler making your A/C run more often and possibly longer.

Chad