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Is there a consensus about shingles?

9K views 41 replies 7 participants last post by  minnesotaroofin 
#1 ·
The fiberglass shingle roof on my home, put on under previous ownership, is pushing 20 years old and, for various reasons, I'm thinking of having it replaced in the spring.
Based on a review of previous threads I'm thinking that there is a consensus amongst the roofing pros that GAF makes a good product. Am I correct about that? What do I need to spec when I request quotes in terms of underlayment, shingles, flashing, nailing, etc? Are there other things I should spell out in and RFQ? Also, I've noticed a lot of posts about ice and water shield - is there a good reason I'd want to use that on any portion of my roof?

My roof is moderatley sloped with north and south exposures. No hips or valleys.
I have a big gable vent on each side of the main house structure and a single gable vent on the smaller part of the house. The attic is well insulated.
Avg. temps here are in the low 30's in the winter, high 70's in the summer. Avg min's are in the low 20's, avg. max's in the high 80's. Jan. is coldest with 25 days below freezing and July is hottest with 12 days over 90.

I can get a lot of ice-build up along the gutters in the winter when there is snow. I currently have a single layer of shingles over felt.

Thank you all for any feedback.
 
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#2 ·
Pipe, You may want to read this.
http://www.palmbeachpost.com/storm/content/weather/special/storm/reports/2004/roofs/index.html
It is a 3 mos. study of why roofs failed during the 4 hurricanes that we endured. There is a lot of info about shingles, testing, longevity and warantees. I don't know where in the mid-Atlantic you are but anyone considering a new roof and all roofers should read this.
Grumpy, I sent you the hard copy today but you can get a jump on it here. I marked the copy that I sent you to show you where I live, less than 2 miles from ground zero for Francis and Jeanne.
 
#3 ·
GAF does make very good shingles. I have had no complaints and no warranty claims.

I don't know your area but I say you let the professionals spec they favored systems then you ask questions. I hate nothing more than when a customer comes to ME with a spec, as if they know how to roof better than I do.

The RFQ should be "Hey I need a new roof, c'mon out and take a look. I live at..."

If you get alot of ice you will want ice shield. You want it at your gutter lines at least. Your goal is to get it 1.5' past the "warm wall". This means if you have a 1' overhang you get 3' ice shield. If you have a 2' overhang your probably gonna want to increase the width of the ice shield. Also put 18" ice shield around the chimney(s) and skylights.

I think your attic is not properly ventilated from what you described. Please post a pic.
 
#4 ·
If you use GAF shingles, and have them installed by a GAF Authorized or Master Elite contractor, be sure to use ALL GAF components in the roof assembly, as there are enhanced warranties available.

These include Weatherwatch ice protection, Shinglemate vapor retarder/underlayment, the shingles (of course), Masterflow ventilation products, and, if using an architectural shingle, an architectural ridge cap.

You will need shingles plus two GAF components to obtain the enhanced warranty on a tear off, and shingles plus one on a roof-over. I NEVER recommend a roof-over. Do it right the first time and you'll be worry free for a good long time. IMO :Thumbs:
 
#5 ·
Teetor, looks like you guys are going to be the proving ground for all shingle manufacturers, at least with regard to wind.

I like your new fancy designer roof colors down there. You guys have always been famous for your flamingo pink stuccos, now you are setting the fashion trends for roofing.



So it sounds like when it comes to roofing and hurricanes you have three problems - the roof itself blowing off, and they are recommending strong ties on trusses and such, then you have shingles blowing off, sounds like that will be addressed by the brand you purchase and its wind shear stength, then finally water getting into the house if shingles blow off, so they are recommending taping seams. What about just covering the entire deck in that water proof ice shield stuff and shingling over it? Seems like that would make the deck water tight if the shingles blow off.
 
#6 · (Edited)
Thanks everybody for some really good information.

Grumpy said:
I say you let the professionals spec they favored systems then you ask questions. I hate nothing more than when a customer comes to ME with a spec, as if they know how to roof better than I do. The RFQ should be "Hey I need a new roof, c'mon out and take a look. I live at..."
I see your point Grumpy. I definietly don't want to pay the "pain in the ass" premium because I'm seen as the customer that's trying to second guess everyone before they've even looked at the job. I'll try not to reveal my true nature too early in the program :cheesygri
 
#7 ·
Mike, Looks like you read the entire article and your assumptions are correct.
The blue roofs supplied by FEMA have a predicted lifespan of 6 mos. Most contractors are at least that far out, my estimates are for November and hurricane season starts in June. Would you like to face the prospect of going through another one of these with blue plastic on your roof?
The photo that you posted is of Palm Beach and they didn't get whacked that hard being on the southwest side. The Northeast side is the one that get pummelled. Look for an ariel view of Port St. Lucie. It was a General Development Corp. community, lots o cheap homes real fast back in the 70's and 80's now pretty much devastated.
I'm peeling up the deck to check/rectify my truss tiedowns and am going to have to do the roofing myself to get the roof that I want.
I posted elsewhere that the Grace water and ice sheild stuck to the deck through 2 hurricanes, saw it myself, firsthand knowledge. It's the only thing going on my house. You can lose all of the purty stuff but his is what is going to get you through the night.
 
#8 ·
Teetorbilt said:
I posted elsewhere that the Grace water and ice sheild stuck to the deck through 2 hurricanes, saw it myself, firsthand knowledge. It's the only thing going on my house. You can lose all of the purty stuff but his is what is going to get you through the night.
Teetor, with mold abatement work almost becoming elevated to the same stature as asbestos abatement, and with litigation and insurance concerns broadening almost continually, do you think there will come a time when the 'risk costs' associated with being exposed to a major roofing failure will be sufficient to make the application of waterproof underlayment a prudent specification across the housing industry?
 
#9 ·
Pipe, I don't understand why anyone would'nt do it. Inital cost is greater but is also a sales tool when the home is sold. IT IS THE ROOF! Whatever you put over it, shinglels, tiles, whatever only protects what is underneath.
I am not a roofer, don't want to be one. I just want a reliable roof up to a Cat 5. Beyond that I'm a statistic.
 
#10 ·
Mike, I want to know how you posted that pic. I could have posted many more a long time ago and none as clean as that, That's Palm Beach propaganda (we lost some roofs). You only know how totalled we are if you are here.
Cute: Firewood is selling for about a buck a log. Last tally at the landfill was costing us about the same to turn it into mulch.
 
#12 ·
Teetorbilt said:
Pipe, I don't understand why anyone would'nt do it.
The answer is simple really. Some guys sell on quality and some sell on price. The ones that sell on price make about the same as the ones who sell on quality, the difference is the ones who sell on price take all sorts of short cuts... like re-using 50 year old roofing felt instead of installing new underlayments.
 
#13 ·
Teetor - to post an image like I did you need to have the URL of the image. Meaning the image has to be viewable on the internet by using your browser.

You can get the URL of any image on the internet by moving your mouse over the image and right clicking it with your mouse button. (try this on the picture I posted)

A menu opens, go all the wall down to 'properties' and click it, another menu pops open and you should see 'URL'

Take your mouse and highlight what is given as the URL. It starts with http and ends with jpg. To highlight hold down the left mouse button and pass the mouse over the text.

When you have it highlighted you need to save it to your computers clip board. Press your CTRL button and the C button at the same time, this is the copy command.

Now to get the image into a post you need to sandwich the URL between the forums image posting command tags which are the "img" tags. You have an opening tag and a closing tag. The opening tag is img the closing tag is /img

The img tags need to be inside of brackets [].

So put the img tag inside the [] then paste the URL by pressing your CTRL and V keys at the same time, that is the paste command. Then finish by placing the /img tag within [] and that will do it.

It should look like this, with the URL replaced with what you pasted.
 
#17 ·
You always have to cut (or space) the plywood roof deck to have breather space. Maily for swelling in humid weater and unswelling(?) for less humid times. You will aways get some moisture condensing between the sheets, so I am told.

Youre right about contrversial. I have never seen a roof with full IWS coverage, nor the need, but I am also not in the Hurricane capitol of the world. I would have to weigh out both sides of the issue before deciding if I would do it.
 
#19 ·
Roofing felt is a vapor barrier which will allow some air to pass through. It is not 100% water tight either. Roofing felt does have a water permiability rating, but I forget now what that rating is.

1/8" gap between each plywood board, but I have never called that "breath" space. That is for a temperate expansions. Yes humidity and heat will both cause the plywood to sweel. If there is not proper spacing between sheets expect buckling of those sheets, and subsequent buckling of the shingles.
 
#21 ·
I'm not a roofer, and I don't even play one on TV, but I do know wood. Sealing a wood surface such as a roof deck completely on the weather side should and could not lead to rot from the weather side. The weather side would be theoretically sealed from moisture - isn't that the purpose of the coating we are talking about here?

The moisture would be from the edge along rake edges and from the underside which would be in the attic. Both of those should be addressed by proper rake edges with proper shingle overlap on the rake and proper ventilation in the attic.

You might cause issues to accelerate in regard to problems that would occur anyways if the venting wasn't correct, but I don't see how you would be causing any.
 
#22 ·
I think Aaron's point is that if the entire top side is sealed 100%, no moisture can escape thus rott can occur. This is actually a topic of much debate between the great minds within the roofing industry. I do see the logic to both sides of the debate.

Some claim that this lack of breathability can be defated with proper ventilation and some claim ice shielding an entire roof substrate simply must never be done... I have seen no proof one way or the other.
 
#23 ·
OK i lied. I do small standing seam with full coverage and still they are all fully exterior roofs, like porches, etc.

Yes, breather space some call it. It is for swelling, Not so much for thermal movement (expansion and contraction).

Yes, you will get air flow over and under roofing felt.

Grumpy, everything has a perm rating. This is why you canot have stasnding water on roofing. Everything soaks water. Maybe not ployurea, but I am still researching this.
 
#24 ·
Grumpy - how do the address the fact that ice shield goes on the lower part of the roof and the wood under it doesn't rot? How is that different than putting it over a greater area? If it doesn't rot under 4 feet of it, or 6 feet or 8 feet I don't follow the logic of how it would rot is you went to 15 feet?
 
#25 ·
Mike I believe the logic behind the idea that the whole roof doesn't rot when only partial ice shield is installed is that because the ice shield is only placed on a portion of the roof there is enough breathability from the remaining area; but like I said I have seen no proof proving or disproving the claims. I just know it is a matter of great debate.

When I see some scientific studies I will then take a stance. Until then I will just keep doing what I am doing.
 
#26 ·
I'm not talking about the entire roof rotting, only the wood under the ice shield. Wood doesn't breath 8 feet along its long axis. Meaning take a piece of plywood and soak it in water for a day, then fully cover both sides with a non-breathing barrier leaving only the edges exposed and leave it for a month, come back and take off the ice barrier and inspect the plywood, you are going to find the edges have dried, but the center probably has a wet spot about 2-3 feet in diameter. Moisture doesn't travel in and out of wood very well longitudily, that is why wood tends to cup, the moisture travels out the broad surfaces. Plywood, that would be the two flat faces.

The point I was trying to make is it is pretty easy to see that the reason why the plywood placed at the edge of the roof with the ice shield on it doesn't rot is because it is breathing from underneath due to proper venting. Think about it, where is the moisture going to enter the plywood from if the weather side is waterproofed? The only moisture is from underneath, as long as the roof is properly vented it should be an issue since no moisture is entering the plywood.

Anybody an experienced wood-worker here now what I'm talking about?
 
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