Roofing my new shop need advice please

[GMJim]

I'm building a 34 X 37 shop and am at the roofing stage. It's getting ice and water but a roofer told me an underlayment such as IKO cool grey and GAF deck armor on the areas not protected by the ice and water isn't necessary. Any roofers out there have an opinion on this?
Thanks
Jim

 

[matt_i]

Some clarity is needed...ice + water the entire thing?

I would place it up to a line that projects down to a plane 2' inside the heated wall.

My experience with synthetic underlayment (Grace Triflex) was outstanding when it came to water resistance and toughness thru weather until it was fully enclosed with shingles. However it could get slippery when wet on a 6:12. Personally I'd apply the underlayment because the building will be immediately water resistant as soon as thats rolled out and nailed down. Then you can take more time doing the shingles, some moisture can roll down between shingles and underlayment during the build process but it will cook out on the first hot days.

 

[wrenchguy]

Pitch? Gutters? Full time heated?

 

[jetnow1]

provides a secondary layer of protection, primary layer while roofing, and makes removing the shingles easier when that time comes at a rather modest cost, I know some
builders who feel the same way as your roofer but I do not agree.

 

[GMJim]

It's a 5/12 pitch and will be heated in the winter and will have 5 inch gutters. One reason I agree with the roofer is the deck armor is $650.00 and not a proven product as it has only been used for about 10 years. I should get 20 years out of a 50 year shingle and I'm 66. I could use the $650 on other things. I have always chosen the best when it comes to work on the house and when I sold my last house nobody cared about the quality. If the dump across the road sold for X dollars my house wouldn't be worth much more and would only be appreciated by very few people.
I agree with all the replies that the deck armor would be better than no deck armor however after speaking with several roofers they all said they only use this stuff one out of 10 houses and this is a garage/shop.
Thanks for the replies I appreciate it.

 

[yeldogt]

I'm with the roofer -- not needed.

I recently installed a real zinc standing seam roof -- Zinc is a great material for a roof ... but you need to protect the underside of the zinc from condensation. The recommendation is to use a full "roof guard" product that incorporates a slip shield. This stops any moisture from the building migrating to the underside of the Zinc .. but there is also a danger of the product trapping moisture in the sheathing. In my case I'm using spray foam -- we paid close attention to proper coverage inside under the deck to eliminate any possibility of moisture getting past the foam. It was Titanium UDL 30 -- it's not cheap and it is VB.

With a typical roof covered in asphalt shingles -- I would only use the code required 3' -- or whatever is typical in your area. I like to use the heavier builders paper (tar) over the what's sold now as "30". The stuff at the big box store is too thin and wrinkles.

Roofs are best when the breath == actually, everything is. An asphalt roof will breath -- tar will breath ... any moisture that comes through the building will breath. Ice shield traps this .. the roof is the protection.

Ice shield is one of those products that is used to fix a problem that really should not occur in the first place -- but, that's another discussion.

 

[blkhonda1991]

are they putting anything down at all or just bare deck above the ice and water? Id go with whatever underpayment the mfgr includes in their warranted assembly.

 

[Falcon67]

Some clarity is needed...ice + water the entire thing?

I would place it up to a line that projects down to a plane 2' inside the heated wall.

My experience with synthetic underlayment (Grace Triflex) was outstanding when it came to water resistance and toughness thru weather until it was fully enclosed with shingles. However it could get slippery when wet on a 6:12. Personally I'd apply the underlayment because the building will be immediately water resistant as soon as thats rolled out and nailed down. Then you can take more time doing the shingles, some moisture can roll down between shingles and underlayment during the build process but it will cook out on the first hot days.

Not Canada, but I have seen several roofs covered with the peal and stick "ice/water" shield stuff. Some roofers seem to like it, I guess because it sticks to the deck and they use less fasteners. Not sure.

I used Triflex on the shop roof and it's good stuff. I ran out and covered the peak with 30 lb felt because I had some. Had a storm come through and all the 30 lb disappeared. Triflex stayed put. Also yes it can be slickery - loaded the roof with single bundles at night to begin work the next day and half of them slid off the roof.

 

[Stuart in MN]

I didn't see it mentioned what kind of roofing material is being used - shingles? Metal?

 

[yeldogt]

FYI: With-in manufacturers many of the products have the same look -- you can't tell the difference once on the roof. The product I used is part of a family of products. Some stick to the roof -- some are a VB w/o stick. Others are a simple base sheet. They all have the same printed look over a top sheet that's anti-slip and able to hold up for 180 days.

In some areas the anti-slip top layer is required and if you are going to be waiting weeks -- having the tougher base sheet product is a plus over old school tar. They also sell a spun product -- looks and feels like a black house wrap.

 

[GMJim]

Update
I talked to a roof material manufacturer (GAF) and they told me to use the ice and water on the eaves (code is to have 12 inches extending beyond the interior wall surface) so a 36 inch wide sheet that covers the 16 inch eave overhang and a 6 inch thick wall but I'm going with two 36 inch wide sheets that will cover 68 inches with a 4 inch overlap. Then to use a GAF underlayment (not the expensive deck armor) on the other areas not covered by the ice and water. I'm using the Timberline 50 year architectural charcoal shingle. All this over a 1/2 inch plywood deck. This cut the cost down to a reasonable amount. The roof should last a while. Thanks everyone for all the input.

 

[brewchief]

As long as you're not simply putting shingles down directly on the osb you will be ok, ice and water on the eves and in any valleys if you have them and then one of the replacements for felt paper and your good. I think the GAF felt buster is fine and is only around 75$ for 1000 sq feet.

After stripping 25 year old shingles that were put directly on OSB and had melted into the OSB and took hours to get cleaned up, if I ran across someone putting shingles down with zero underlayment I think I would push them off the roof.

Sent from my SM-G965U using Tapatalk

 

[86turbodsl]

50 year asphalt shingle??? ha ha ha. More like 20 if you're lucky. The flatter the roof, the shorter the duration.

 

[GMJim]

Pitch? Gutters? Full time heated?

As long as you're not simply putting shingles down directly on the osb you will be ok, ice and water on the eves and in any valleys if you have them and then one of the replacements for felt paper and your good. I think the GAF felt buster is fine and is only around 75$ for 1000 sq feet.

After stripping 25 year old shingles that were put directly on OSB and had melted into the OSB and took hours to get cleaned up, if I ran across someone putting shingles down with zero underlayment I think I would push them off the roof.

Sent from my SM-G965U using Tapatalk

Yeah this is a new plywood deck, all new construction.

 

[GMJim]

50 year asphalt shingle??? ha ha ha. More like 20 if you're lucky. The flatter the roof, the shorter the duration.

Yeah the 50 year shingle is in dog years. Knew that going in but they're better than the 25 year shingles that last 8 years!

 

[yeldogt]

Yeah the 50 year shingle is in dog years. Knew that going in but they're better than the 25 year shingles that last 8 years!

I did 40 year presidential about 25 years ago. I put a small addition onto the house around 5 years ago and wanted them to match. Even with the 20 year difference -- you can't tell. Celotex was the original manufacturer --- bought by Certinteed. They now make two thickness -- the one that matches mine is 50 year and the new thinner version is 40. Maybe mine are really 50

Glad you could get an answer from GAF -- some companies are better than others with qualified people to answer questions.

 

[Falcon67]

50 year asphalt shingle??? ha ha ha. More like 20 if you're lucky. The flatter the roof, the shorter the duration.

Double haha - 10~15 in west Texas if you're lucky.