Low slope roofing options

I had a roofer give me two estimates. One to remove and re-roof the entire roof along with replacing the damage decking over the back section of the house. The other estimate is for only removing and replacing the decking and re-roofing. He informed me that the back section of the house where the turtle vent caused severe damage to the decking has too low of a slope to shingle according to code.

Is this accurate based on the photographs for this section of the roof? I apologize that the 2nd picture is not very clear but it is the only one that I had from that angle.
When did the code change?

As you can see the slope is connected to a steeper slope and I am concerned about how that section from that ridge to where the low slope connects would look, but I want to do what is best.

We didn’t have any drainage problems with the first roof, and the leaking on the second roof appears to be caused by the turtle vent, therefore, I don’t believe that the low slope caused any of the issues or had drainage problems.

IMG_0892 IMG_0893

The current “standard” shingle is different than what was considered standard 20 years ago. The current shingle (architectural) doesn’ drain water as well on low pitch roofs and the old (3 tab). That is the primary issue.

That makes sense. I am sorry but I just edited the post to include the pictures.

Looks like a 3/12 pitch to me from the pic. And I do consider that “iffy” about installing shingles on. Is the section visible from anywhere? If not, I see no reason not to just install one of the products designed for low slope roofs (there are several options I consider acceptable).

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Code is shingles may be applied to a 2/12 to 4/12 but requires a double layer of felt. Code also requires installations to meet Manufacturer’s Specifications. Manufacturer’s Specifications trump code. I believe Manufacturer’s Specification do not allow for laminated shingle to be applied on slopes less than 3/12.

I think your best bet is to either install roll roofing or a more expensive membrane. I suspect that low pitch isn’t very visible. If it is, then apply Ice & Water barrier to the entire low slope and then install the laminated shingles. Install a good brand of Ice & Water, chances are reasonable you’ll need it to perform well. And use a competent installer who knows how to properly install a turtle vent.

Not really visible from anywhere. Do I need to be concerned about how the shingled area on the slope above the kitchen connects to the low slope dining section?

If your roofer was knowledgeable enough to know that shingles aren’t the best option then I think they would be knowledgeable enough to tie the different types of materials together properly. It’s not that difficult.

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You’re right it isn’t very visible. Do I need to be concerned about the different roofing materials on the slope of the kitchen connects to the low slope of the dining room area?

I plan to eliminate the turtle vents since the ridge vents and soffit vents were installed.

Thanks and you might be right, but I am just trying to learn as much as I can so that I am not put in the situation that I am in now, ever again. Besides that I was clearly not talking to a roofer, but a salesman that by the way used to do pest control. I have 2 more companies scheduled to come out to give me estimates.

Regarding the installation instructions. I don’t think I am looking in the right place, when I look at the codes, it refers to Installation by Manufacturers instruction, but then the Manufacture information says to refer to local code.

Dont be scared to use shingles,just put some ice guard underneath and 4 nails in correct place per shingle would work.
I’m not sure bout prices for sbs layers vs epdm,pto+ iso board vs ice guard + shingles. Latter is easier to slap on in wall adjacent area so you dont have to pull siding off and able work with babytins.

Need to be careful with your wording. “Slapping” things together makes the customer wince. We “scab” rafters together, but around the customer, we “sister” them together…

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What brand of shingles are you installing?

There is no concern with “mixing” materials. It isn’t two unlike metals corroding when they touch. Use the right material for the right job. Good to get rid of the turtle vents. They were useless without soffit vents anyway.

I already have soffit vents, the turtle vents were supposed to be eliminated when the ridge vents were installed and they were removed. 2 years later I had a leak and the roofer reinstalled 2 of the 3 turtle vents. But it appears that the turtle vent continued to leak. Of course I now know that mixing the ridge vents, turtle vents, and soffits was not a good call on the roofers part. And the good news is no one ever fell through the third time turtle vent.

The bad thing is that I don’t know how much ventilation that I’m getting from the ridge vents because none of them are cut in all the way. A slot here. A slot there. Looks like the tried to cut it in on both sides here or there but only got a few inches through. And the area above the garage has soffits and a ridge vent, and a gable vent up high near the ridge.

Now I’ve got to figure out how to figure out what is going on in the other section of the house. From the outside looks like Ridge vent was installed, gables, and turtle vents. This attic space in the upstairs of a cape cod house and the only access is in the top of a linen closet. I can’t imagine that it’s very high but I know it has duct work whereas the attic space over the back part of the house doesn’t.

I noticed a few months ago that the foyer at the front door, the drywall tape had started to lift. I had it repaired and was getting ready to paint but now I am certain that it is a symptom of the roofing ventilation issues that are going on because all the different types of vents are not playing well together.