re roof

[rtwills]

i am about to redo my roof. From previous posts I decided to go with Landmark shingles.I have alot of "cupping" on my current shingles. I have 5 vents for a 40' run.i am wondering if I block those vents and install a cobra vent would that stop the problem or should i just cut in a couple more standard vents?

[Surface Tension]

How old is your roof? Cupping is thought to be caused from improper venting. I have yet to see a roof that prematurely failed from cupping and I've been on hundreds of old homes that didn't have any roof vents. Yes I've seen cupped shingles but they were 30 years old too.

Need to know you sq footage, better yet, volume. Are your soffits vented? Are your roof vents toward the peak? Yes you could go with the scrim type material on the ridge. Personally I like the roof vents. As long as they're placed right they work very well.

[rtwills]

it is about 15 years old.yes soffits are vented. vents are 18" down from peak (5 of them) . upper floor is 40x36, 5/12 pitch.I have about 20" of insulation in attic and yes there are chutes installed.currently there are 3 standard vents and 2 whirly bird vents up there.

I have done a few roofs but dont know alot on the specs of the different vents.I noticed alot of ridge vents lately and was wondering the difference on performance wise and if it was worth changing to.I plan on being here awhile so I dont want to run into issues later.

[Roofer]

I would recommend a ridge vent. It looks better (IMO), and works better.

A couple options for ridge vent. Cobra works good and doesn't show as much. We like to use Omni-roll. It vents a little better than cobra, but it shows outside of the ridge cap. Some people don't like that.

I would also suggest using Roofer's select for the felt. Lays much flatter and is much tougher. It will make an all around better job.

Another suggestion is to get rid of any aluminum roof edge and use steel. Where gutters are you can make a gutter flashing out of break metal, but for the gables use steel edge.

[Roofer]

Your shingles are probably cupping because they are the older all asphalt shingles. The ventilation sounds like it is enough, but ridge vent will work better.

[sparcebag]

Roofer why steel edge,rather than aluminum? chipping & rusting??

[BucksnDucks]

Being the roofing business myself also for over 13 yrs, I can agree with what Roofer posted. He hit every nail on his lines! Reason of steel over aluminum is its just plain stronger and is less likely to bend or lift in high winds and hail. Hope we got you pointed in the rite direction! Stay away from box vents and whirly birds, just another spot for ice damage to build up!

[Roofer]

The aluminum edge tends to also show bulges and bends because it moves so much in the weather. Steel stays nice and flat and is much stronger. We also use steel fascia's. Less bending and is much stronger.

[rtwills]

Thanks for the replies I think i'll go with the ridge vent and thanks about the edging,I'll look for the steel stuff.