What is best type of venting for a roof?

Question

We are redoing our roof and have had several different suggestions for venting. We have a decent size house and only 1 roof vent, so we know this is inadequate. Been told to do 1 "power vent" and told that you use this instead of other vents rather than in addition to? Someone else said just put 5 or 6 more roof vents. Another told us to do ridge vents, I think they were, along the top of the roof. We have a split level house and it is already difficult to keep it cool because it is so open to the lower level. Any suggestions best venting to use to maximize keeping attic cool? Thanks so much.

Answer 1

There's more to it than just adding more roof vents. Venting a house properly requires "make up" air and "exaust" air. To make it simple, air must flow in before it flows out. Just adding "hat" vents to the roof won't make a whole lot of difference if there is no air flowing in to feed them. Adding soffit vents is a common solution if you don't have them already. (those would be vents in the roof overhang, or eves) They will provide the incoming air, and, as hot air rises, a ridge vent will carry the moist, warm air out the top of the roof. "Hat" vents will also work here, just not as good. As an alternative, gable vents (vents on the side of a house near the roofline) can be used for incoming air if soffit vents can't be used, they are just not as efficient. To answer your question, the best venting would be a combo soffit and ridge vent

Answer 2

Dont know what is best for all situations, but what has been working well is a ridge vent,
Have a shallow pitch on upstairs roof w/ very small attic space & it was uncomfortable in winter & summer .
Had a re -roof done & went w/ ridge vent.
The logic was that a ridge vent is at the highest point & hot air would exit as it rises.
Also, it would take quite a few regular roof vents to equal the venting area of a full length ridge vent.
Also left the peak vents on both ends in place.
The re is no insulation on the roof rafters just between ceiling joists..
Had a thermostat controlled power vent that proved to be noisy & ineffective.
The ridge vent solved our problem.
Might be worth discussing w/ your roofer if you have similar situation.
Best regards.

Answer 3

Yes, split levels are a mess with venting and also with HVAC. The scourge of housing design, I'd never live in one. But now that you're in one, let's discuss the options.
Power vents......well, there are two concerns. One, is what if the things stops working or shorts out or the thermostat goes bad. Then you're either not getting proper venting or the house burns down. Personally I stay away from power vents because I don't like having to rely on their reliability. Secondly, even with a powered vent, split levels that I've deal with are vented so badly that even they can't seem to move the air through the attic.
Lots of roof vents will work. I personally would prefer this over a power vent, and they work pretty well, but then your house roof looks like the roof of a restaurant with all the metal venting exposed.
I would lean toward the ridge vent. They'll do an OK job in your application, and they have the least impact on the aesthetics of the house.
If you permanently want to solve your venting and HVAC problems, though, plan on selling your house sometime in the next 10 years and getting away from split level. It's just impossible to both heat and cool them evenly, even with a very expensive zoning system. Because the attics are boxed in and separated, they just can't move air through the attics, either.

Answer 4

This Site Might Help You.

RE:
What is best type of venting for a roof?
We are redoing our roof and have had several different suggestions for venting. We have a decent size house and only 1 roof vent, so we know this is inadequate. Been told to do 1 "power vent" and told that you use this instead of other vents rather than in addition to? Someone else said...

Answer 5

Ridge venting combined with eave venting promotes natural convection ventilation. The air flows in through the eaves and out through the ridge vent which are at the highest point on the roof. There is no hot air trapped at the ridge as can happen with regular roof mounted venting.

It is not the number of vents but the effective ventilation area that counts.

Minimum venting is 1 square foot of vent for every 300 square feet of roof surface. That is 1 square foot of vent on roof and eaves. Area of the roof is the actual roof surface. If it takes 3000 square feet of shingle materail to cover the roof, the roof area is 300 square feet. That would mean 10 square feet of effective ventilating area. Vents should have an effective ventilation area stamped on the label.

Check with your local building regulations for the actual venting requirements.

Good Luck

Answer 6

We had two turbine vents put in our roof to supplement the two small gable vents. When we had an addition built on, one had to be removed to make room for the reconfigured roof. The contractor put a "biscuit" on the addition, which automatically runs when temperatures in the attic exceed 120 degrees Fahrenheit.

Still gets hotter 'n' a pistol up there anyway.

The attic floor is well insulated, so that heat doesn't get into the house. We do have a zoned system, with one heat-pump/AC upstairs and another down. It was worth the cost.

Answer 7

I LIKE THE RIDGE VENT THIS WAY IT IS VENTED THE WHOLE WAY DOWN THE ROOF. HAVE YOU THOUGHT OF PUTTING IN A GABLE VENT? WE HAVE ONE OF THOSE WITH A BOX FAN IN IT SO WHEN IT GETS REALLY HOT WE JUST PLUG THE FAN IN FOR A COUPLE HOURS. GOOD LUCK!

Answer 8

leave a hole