Opinion on dormer vents

I have a small ranch with hip roof, 2100 sq foot attic space. I would like a passive ventilation system. A builder told me the only way to get enough exhaust venting is with Air Vent B-144 and use 4 of these and some RVO-38s as well. They are so ugly.

No one ever uses the dormer vents in Oregon but they look aesthetically more pleasing, not sure of rain intrusion. Any opinion on dormer vents and what a good brand might be? The ridge of my house is 15 feet long with 5/12 pitch.

I meant a roofer told me to use Airvents 144 for exhaust venting. BTW, I’m reroofing the house at the same time.

If you want something passive and maintenance free try two of these.

They carry a lifetime warranty and cost just $50 each.

Use 14 inch. The 12 inch aren’t worth 50 cents.

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You could add hip vent to the top portion of your hips, near the ridge.

Turbine vents are notorious for drawing in snow in my area, I avoid them like the plague.

Ann, snow would be a non issue in the southern states. What area are you in?

The B-144 vents are basically a power vent casing with no fan inside it. They won’t do much of anything. All those vents are not necessary.

One power vent would ventilate the whole attic unless there is more than one attic space.

15 feet of ridge vent would be too passive.

Do you have soffit vents underneath the overhang of the house for the intake air?

Axiom, I have lots of hip seams. I think running the hip/ridge product all over the roof would really muck it up and make things look overwhelming. I’ve been told that the hip/ridge material should be run on every seam. Just the ridge portion at the top is not long enough to accomplish the required amount of exhaust ventilation.

LuckyChucky, I live in Oregon in the Willamette Valley. Mostly we get lots of rain, maybe one snow a year or less on valley floor, not much. I think turbines look as ugly as the big B144 vents.

Still no opinion on dormer vents anyone? I’m working towards approx 726sq intake and exhaust ventilation. Sigh, maybe I should just get a power vent and call it good.

Lucky Chucky, Yes I have under eaves vents, or what folks call bird blocks. The 2x4s blocks have small screen holes and the plan was to remove all 22 of them and put in eaves vent screens that have 30-33 sq inches intake each.

If by “dormer vents” you mean what we refer to here in the extreme south as “wooden gable vents”, then I don’t recommend those. They do not vent very much at all and are prone to leakage and rot when they get older.

I’ve been a “repair” specialist for over 28 years and very often I’m called to some of the older areas of town about a leak to discover upon arrival that it’s the gable vent. Usually the corners at the bottom of the valleys but sometimes its blowing rain getting in the gable vent. I “Always” recommend removing them from the roof, decking in the hole and installing a more modern type of ventilation according to the specifics of that particular home.

Sounds to me like the power vent is your best solution. Just remember all power vents are NOT created equal. The 1170 and 1250 cfm ( cubic feet per minute ) only come with a 5 yr. warranty on the motor while the 1600 cfm carries a 10 year motor warranty and only costs about $75 more per unit to purchase. The casing is also very superior to the lower classes.

You can have an on/off switch installed between the power source and the thermostat for ultimate “control” of the fans. Also, if they are not too high up in the attic, the thermostats are easy to adjust between 50 and 120 degrees. Check with the manufacturer for the recommended setting in your area. Start with that and “tweek” it to your liking. :slight_smile: