We just received our first set of estimates for a new roof, and the contractor priced out both can vents and ridge vents. What’s the difference? Pros and cons to each option?
Ridge vents draw air equally across the ridge, can vents will pull from isolated areas … Ridge vents will give you a more consistent attic temp. Heat rises, the ridge will be the highest elevation relief.
If by can vents you mean wind turbine or another penetration the answers are as follows.
Can Vent
Pros: Cost (it is more affordable to put a few vents on your roof, whether its when doing a complete reroof or just upgrading your existing roof).
Cons: Wind turbines have to be capped if a hurricane is going to hit.
- When they rust out they will begin to make squeaking sounds.
- If there is no wind you basically have a 10" diameter area in which hot air can escape.
- During wind you still only have an approximate 5-10 foot diameter around the penetration
which will be sucking out hot air
- Rodents can get in through the hole
- Appearance (personal opinion as a roofer) I think it makes your roof look like a restaurant
Ridge Vents:
Pros: Continuous are circulation regardless of wind
- Sleek design that won’t affect the look of your roof
- Rodents cant get in
- If you have enough intake (soffit vents), you can install ridge vents on all of your ridges for a maximum amount of ventilation
- 40 feet of Ridge vents = 10 wind turbines or 18 conventional roof vents.
Cons: Price (semi con) when doing a re-roofing if you install 40 feet of ridge to 10 wind turbines the
the cost of the turbines is actually more, but if you’re only putting 2-3, the turbines are more
affordable. When upgrading your current roof it is more economical to just install the turbines.
As you can see I favor Ridge vents to can vents any day of the week; its better for your roof and no maintenance is required on them.
Hope this helps,
Daniel- Florida Standard Roofing
Box vents are your cheap alternative. Only reason we use them is if there isn’t enough ridge to properly vent the roof. Box vents also isolates where the air is being pulled from, leaving the roof not properly ventilated in some areas. Your roof life seems to diminish with box vents.
Ridge venting is a more costly way to go but if your roofing contractor is up front and honest the price will vary minimally. It is in my eyes the best way to properly vent a roof. We are Preferred contractors for Owens Corning and ventilation is huge in their eyes. The shingles will last a lot longer if properly vented. So don’t let your contractor talk you into box vents if you can put on ridge venting.
In my professional opinion, ridge vents are best. It is the most updated ventilation system. However you need to have soffit vents swell. Soffit vents act like the intake of air and the ridge vents like the exhaust. It allows better breathing of the house.
Jason
We stop using can vents (turtle vents) about 3 years ago and only start using ridge vents ( GAF cobra vents or smart vent when there isnt enough of ridge line) . Why? Ridge vent is the best option for attic exhaust ventilation , has clean look and leak proof if installed correctly . It also would not allow birds to enter or nest in your attic ( common problem with can vents) .
I’ve had a couple contractors looking at my roof. Its going to be a complete tear off, I like the ridge vents but one contractor told me that ridge vents only work if you have vented soffits? Is this true?