Closed Valleys vs. Open Valleys

We are having a new roof installed on our Cape Cod style house with a 7.5 / 12 pitch and I have a few questions.

We would like to use the GAF Timberline Ultra HD shingles (the “Ultra HD” shingles are 53% thicker than regular Timberline HD shingles). Our roofing contractor has recommended “closed cut valleys” on our dormers and porch roof.

The average temperature for this time of year in our area is between 35 and 55 degrees. I am concerned that given the cooler temperatures and the thicker shingles that the shingles may be more brittle and may crack or delaminate when the contractor bends them to create the closed valleys in our dormer roofs.

My question: Do I have a legitimate concern? If so, should I ask the contractor to use “open copper valleys” instead?

Also, is there a noticable difference between the “Ultra HD” (thicker shingle) and the standard “HD” shingle when one looks up at the roof from the street? If not, would it be better to go with the standard “HD” shingle which is probably more pliable when creating the closed valleys?

Thank you for your advice,
FJ

GAF makes the thinnest shingles on the market.

Each valley is good it depends on the person installing them.

Open copper valleys are very nice but pricey.

Some areas are predominantly open valleys while others are predominantly closed cut or a variation thereof.
What do you see most of from your front door?

You seem to be impressed by the thickness of the GAF HD shingle, really it’s not impressive at all.
Look at a Landmark TL, that is impressive.

IMO you should take the money for the open copper valleys and get a better shingle and let the roofer do closed cut valleys.
More bank for your buck there IMO.

I’d have to dig through some technical docs, but if memory serves me right, GAF recommends open valleys in areas that get snow.

[quote="-Axiom-"]GAF makes the thinnest shingles on the market.

Each valley is good it depends on the person installing them.

Open copper valleys are very nice but pricey.

Some areas are predominantly open valleys while others are predominantly closed cut or a variation thereof.
What do you see most of from your front door?

You seem to be impressed by the thickness of the GAF HD shingle, really it’s not impressive at all.
Look at a Landmark TL, that is impressive.

IMO you should take the money for the open copper valleys and get a better shingle and let the roofer do closed cut valleys.
More bank for your buck there IMO.[/quote]

+1 on that,But man open copper valleys look soooooo damn good. :smiley:

Thank you for your recommendation Axiom. There is a mix of open and closed valleys in our neighborhood. The contractor is a GAF Certified Installer, that’s why he is recommending the GAF products. The shingles come with a limited lifetime warranty, so I am going to ask him to install the GAF Timberline Ultra HD shingle - the thicker shingle.

Since we are going with the “thicker” shingle, (or if we take your advice and ask for the Landmark TL - a nice looking shingle) I am going to ask for the open copper valleys for the following reasons:

  1. A closed cut valley will require the shingles to be bent to fit into the valley.
  2. The temperatures now in our area range between 35 to 55 degrees - it’s only going to get colder.
  3. I am concerned that the “thicker” shingles may be more brittle given the current temperatures, and may crack or delaminate when the contractor bends them to create the closed valleys.
  4. I am worried that the “thicker” shingle may not lay flat in the valleys.

Since you are in the trade, can you offer any tips or suggestions about installing a roof in colder weather? The job probably won’t start until December and it will be much colder then.

Do I have legitimate concerns with installing thicker shingles in a “closed valley”? Will the colder temperatures be a concern?

Thank you again for your advice.

FJ

In cold weather installations something we do is this,tear the roof off,then felt the roof,then open bundles of shingles and spread them out over the roof.Let them warm up.The sun against the felt will warm the shingles up making for a better winter installation.

I generally never just start opening bundles and start nailing right out of the package in cold weather.Taking an hour or so to let the shingles relax and warm up is worth the effort IMO.

Sometimes its not always possible but roofing with the sun during the winter is in your favor.

We’ve installed many roofs in Indiana in Nov and Dec, mostly Architectural. We do all closed valleys. We’ve never had a single problem with what you’ve described. I agree on using something other than GAF. I won’t use them unless the customer is adamant.

I agree with Axiom on the Certainteed Landmark TL over GAF.
I also agree with Roofmaster about laying shingles on the tar paper in the sun. Doesn’t take long to make a HUGE difference. Not that I expect you to instruct your roofers on what to do lol.

Yes your concerns are legitimate. Bending a shingle in the winter time can crack it. That’s not to say that pressing it into a valley is going to. I install roofs all winter long up here in Canada and I have never had an issue.
Quality installation is just as, if not more important than a quality product.

Thank you everyone for your input and advice, I really appreciate your help.

FJ

We too are GAF fans. We install in Vermont in anything above 20 degrees and rarely use open valleys and no issues with shingles not sealing nor cracking.

I put Timberline HD’s up against any shingle with cold weather testing and the “thinnest” shingle on the market according to some- is a way more flexible than say CT of IKO. My second cold weather choice would be OC.

Thicker does not always mean better.

Ain’t what she said. :badgrin: