Roofing\venting proposals = Confused homeowner

2Kwiet

I'd appreciate any thoughts the pro's might have on the proposals I received to put a new roof\venting options. What would you do given the below info

I live in Phoenix AZ, the house currently has 2 vents on both gables, near the bottom of attic space, 4 turbines and a couple of box vents all on back\south exposure, no soffit vents. I'm sorry, I don't know what you'd call my roof, but it's not flat and it doesn't have a steep pitch, '70's ranch, single story. 34 sq's (including garage that is keeping 1 turbine).

Roofer 1 = remove turbines\box vents and install 2 20amp solar fans, my choice of OC, GAF or Malarkey for shingles
Roofer 2 = remove turbines\box vents and install 15 low profile O'hagin vents, OC shingles.
Roofer 3 = remove turbines\box vents and install 2 20 amp solar fans plus put 3 soffit vents across front of house (currently has birdblocks?), Certainteed Landmark.

All 3 roofers have been in business at least 10 years, I checked the State contractors website and confirmed, checked for actions, I choose these 3 based on a bad hailstorm 2 years ago - a number of companies lost their reputations subbing out the work, and these 3 didn't - 95% of the homes in my area had roof repairs or replacements, so this was important to me. I've read, I've researched, and I still have no clue what the best choice is, especially for the venting. There's a 3k spread in pricing which I'm leaving out of the picture since I'm trying not to put price at the top of the list.

If you were in my shoes which would you choose? Modifications that you'd recommend, etc?

I really appreciate any and all feedback. Thanks

joecaption

Picture of the outside of the house would be great.
I'd wonder why not one of them suggested using ridge vent instead of vents that only vent in a circle, run to slow to exhost much air, do not vent 24/7.

smalpierre

Joe - Ridge vents don't work as good as a powered vent. For them to work well at all, the intake / exhaust must be properly proportioned. They also work via the sun making the attic air hotter than outside, creating a convection current, so they don't vent at night either.

I use Attic Breeze solar vents. I'm not a fan of GAF solar vents. In most situations I run across, solar vents with properly balanced soffit ventilation is best. Too much or too little intake ventilation is no good - not as much of a problem with a forced air solution than a passive solution like ridge vent.

joecaption

Your joking right?
So at night the laws of nature change?
Heat rises, plain and simple.

bcdemon

I would go with Roofer #1 and definitely choose Malarkey shingles over those other POS. Malarkey gives the installer a 2" tall nailing area, whereas GAF gives you a chalk line to nail on, miss that line and there goes your manufacturers warranty.
And heck, you can take the Malarkeys and put the GAF warranty on it with their "Your Choice Warranty Program".

CIT

2Kwiet - you are confused because THEY (the contractors) are confused. I have 7 bids laying in front of me at this very moment and NO two suggest the same ventilation solution. Even the very professionally written proposals differ. I read that improper ventilation can take 60% of the life of your shingles so it is a real concern to those of us who live in a hot places like you (and I). I too have gable end vents (one powered by a fan) on the East West sides and I think I am going with a contractor who wants to knock out several soffit blocks on the south north sides and replace them with screens. He then wants to install some O'Hagin or dormer vents up higher for exhaust. Not sure if the gable end vents then should be closed off or not. The whole ventilation thing is either very misunderstood or else they are overstating it's importance and maybe we don't need to worry about it as much as we think. Many of the contractors don't address ventilation at all. Signed, "confused too".

AndyGump

Roof venting is not to cool the roof down, it is to remove any moisture that may accumulate in the attic.

Andy.

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CIT

Kweist- I ran across this article and thought you might like to read it. They wouldn't allow me to upload but here is the link:http://www.finehomebuilding.com/PDF/Free/021221068.pdf

CIT

Andy Gump: The article I refer K2weist to states:


Theory behind venting
The intent of roof venting varies depending on climate, but it is the same if you’re venting the entire attic or if you’re venting only the roof deck.

In a cold climate, the primary purpose of ventilation is to maintain a cold roof temperature to avoid ice dams created by melting snow and to vent any moisture that moves from the conditioned living space to the attic. (See “Energy Smart Details” in FHB #218 for more on ice dams.)

In a hot climate, the primary purpose of ventilation is to expel solar-heated hot air from the attic or roof to reduce the building’s cooling load and to relieve the strain on air-conditioning systems. In mixed climates, ventilation serves either role, depending on the season.

Just FYI, you may the correct and not the article. Thanks

Windows on Wash

+1

Love the Malarkey shingles. Just can't really get them out here.

There is a gross lack of understanding when it comes to ventilation amongst roofers.

Ventilation has little to do with shingle cooling and the biggest impact on shingle life would be in lower slope applications and moisture accumulation.

+1

+90% of the cooling happens to outside. Very little comes through the roof deck and into the attic.

An overwhelming majority of the cooling happens to the outside of the home. If you have anything over a 3:12 pitch, convection takes over and your cooling is to outside.

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Gary in WA

1. Is the attic floor air-sealed?

2. What is R-value of the insulation now? Type/thickness?

3. Any HVAC ducting/units in attic?

4. Are you having moisture/mold problems with existing venting?

Gary

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Gary in WA

A good read; http://repository.tamu.edu/bitstream...pdf?sequence=1

Gary

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2Kwiet

Here are some pic's of the house, with where the existing gable vents are.

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2Kwiet

1. Is the attic floor air-sealed? I'm having a home energy audit done next week to answer that question. My feeling is, nope. Within reason, I'll take action to make it so.

2. What is R-value of the insulation now? Type/thickness? - it's blown in, other then that, I can't answer.

3. Any HVAC ducting/units in attic? - The a/c unit sit's on the roof, so probably most of it is up there.

4. Are you having moisture/mold problems with existing venting? - I don't believe so. I've never been in the attic, so I guess I'll find out next week if there's anything up there that's an issue.

2Kwiet

So to help me, or to muddy the waters more, I decided to get a fourth quote, and it ended up kinda doing both. The estimator's first thought was a ridge vent, and then he saw I didn't have any soffit vents, and he said it wasn't an option. When I asked about having soffit vents put in, he said that their license was for roofing, and didn't cover structural changes....?? Okay, so does this make sense? My concern is, that along with the roof, I asked everyone about redoing a patio area that currently has a metal roof, which is going to require reframing to tie in with the roof and support the change - and all of the other roofers quoted me on that portion of the job. I double checked roc again, and as far as I can tell, everyone has the same type of residential roofing license. A couple also had insulation, but none of them had anything that would suggest structural changes - like a general contractor or whatever. Second - is putting in soffit vents structural? If that's structural, then what keeps making a hole in the roof and putting in a vent, non structural? His venting suggestion was putting in louvered vents to replace the box vents and nothing else.

And to you all, thanks so much for your replies, and I'm sorry for the delay in answering. i asked for notifications and got a total of one, so just realized today that there were more to read and reply to.