Nail placement in 3 tab seal tab shingles?

[DJW]

Ok I have read the directions on my Owens-Corning shingles. However when I started to remove the existing old shingles I see they were nailed in the tar seal strip. Now I am not sure if back 27 years ago the installer had used nail guns. But the shingles are dried and very bad but still I have no leaks. Aside from the warranty being voided isn't this a good place to put the nail for the following reasons?

1. The tar will seal around the nail shaft and the head after the sun has done it's thing.
2. The sealing might stop the nail from popping up in the future.
3. The nail is a bit farther up from the above courses tab's lower edge. I am amazed that the nail is so close to the edge of the overlap anyway when installed via the directions. I would think if anything that the nail should go above the tar seal strip. That way any water that might be pulled up under the shingle by capillary action would be stopped by the seal of the two shingles before reaching the nail. What do you think?

[Chas Hurst]

Both Tamko and Certainteed specify nailing in the sticky strip and this is the way I have always done it. I don't know where the information comes from that nailing in the sticky strip is wrong.

[marson]

I hadn't heard that you should nail in the sticky strip...obviously some shingle manufacturers are different. Owens Corning and GAF both don't allow nails in the strip. The strips' sole purpose is to seal down the flap of the shingle above, to prevent blow offs and wind driven rain. If you put a nail in it, it will inhibit the sealing, especially if the nail is a little high. I once wound up in court over a roof, and the owner had a fancy inspector come and look at the roof, and that was one of the few faults he found--nails in the sealing strip. I guess if you really want to cover your ass, you read the directions for each brand.

[Matt Whiting]

The nails cover up part of the sealing strip and also place a depression in it. This reduces the effective length of the sealing strip and hence the amount of force that it can apply to the shingle being sealed to it. Nailing in the strip is a bad idea and you want to nail slightly below the strip per the shingle manufacturers instructions.

Matt

[Matt Whiting]

The information comes on many shingle packages.

I looked up the Tamko instructions and they clearly say to NOT nail into the adhesive strip. Go to the url below and open the instructions pdf.

I wasn't able to quickly find installation instructions at the Certainteed site, but I'd be very surprised if they recommended nailing in the sealing strip. Can you provide a url to where you claim they make this recommendation?

Matt

[Matt Whiting]

Precisely.

Matt

[Mike Hammer]

[Chas Hurst]

The directions in the pdf for the glass seal 3 tabs show the nailing area to be the sticky strip.

[Dave]

27 years ago they primarily used "big heads" on shingles. Yes, there was a pneumatic nail available. The difference should be obvious by the visible clue of observations.

2 layers of shingles is enough. Don't go there from what based on what I've read.

[Matt Whiting]

>

The word choice is poor, but I believe you are reading this incorrectly. I believe they are saying that the nails should be on the line shown either just above or just below (preferred) the sealing strip. Zone is very misleading and certainly suggests that nailing could occur anywhere between the lines. If you read the detailed instructions at the link I posted above, you will see that it says clearly that nailing should be above or below the sealant in the area from 5/5" to 6.75" up from the tab edge. It clearly says DO NOT NAIL IN THE SEALANT.

I have NEVER seen a shingle manufacturer recommend that nails be in the sealant strip. Always just above or below, with below recommended as it places less bending stress on the shingle and thus resists tear-off better.

Matt

[Matt Whiting]

>>

No, you are reading the diagram incorrectly and the word choice is very unclear, but if you read the detailed text instructions it makes it very clear that you are to nail above or below the strip and not into it. But, hey, it is your roof and your warranty to be voided so what do I care? Nail in the strip if you like.

Matt

[Mike Hammer]

OK. I agree with you that for warranty purposes one should not nail in the sticky strip. But seriously though, six 3/8" or 7/16" nail heads are not going to reduce the surface area enough to make any pratical difference if you have a good flat surface to work with. Usually there's a good reason behind, "Don't do that!," but not always.

Mike

[Michael Bulatovich]

Look closer.... ***close to or on*** the strip. The strip is to get the layers to stick together, not a nailing target.

[Michael Bulatovich]

I stand corrected. (I've never nailed ON the strip, but the diagram seems to include it.)

[longshot]

this looks pretty simple to me. how is anyone confused? the zone includes the strip. BTW: any successful roofing contractor has guys with coil nailers, slinging shingles at unreal rates, the nails will be all over that strip in about a 3 " zone ~ everytime.

[longshot]

you will never find a single roofing manufacturer pay you to replace your roof, regardless of where the nails are. The warranty is completely worthless. you think 30 year shingles should be inspected after 29 years to make sure they are ok, if you find some unusual wear than the manufacturer is going to come out & replace them??? that's pretty funny really.

[Matt Whiting]

>>>>

>> Yes.

It isn't just the area of the nail head, the nail can also depress a larger area around the head. If you lose 2" of length of the sealing strip for each of 6 nails, that is 12" of the 36" length of the shingle. Losing 1/3 of the sealing force is VERY significant. Even if you lose only 1" that is still 6" out of 36" or 17% of the sealing strength. In a high wind situation that very well could be the margin between a tear-off and an unscathed roof.

I know it is hard for many people to accept that the people who actually make a product know more about it than those who use it, but that is often the case.

Matt

[Matt Whiting]

I agree that the diagram is not clear at all. However, the text is quite clear and is correct.

Matt

[Matt Whiting]

What part of "do not nail in the sealing strip" in the instructions didn't you understand? The diagram is not clear and the written instructions make it very explicit as to how to nail the shingles.

Yes, I agree that most roofers do quick and shoddy work. And, apparently, most can't read either.

Matt

[longshot]

95 % of all roofs in the world with asphalt shingles are nailed the same way. It's fine. don't read into it so much. The shingle manufacturer is NOT going to buy you a new roof under warranty anyway. no matter how long the roof lasts.