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David
Roof Nailing

We will shortly have a new architectural roof put up on a 1924 colonial with 1x7 tongue and groove decking. Most of the wood has held up very well for the 88 years, a few cracked pieces we can replace with extra same-size pieces from the attic floor.

Opinions from roofers vary; obviously there will have to nails coming through the decking between the roof joists. The question is where to avoid having the nails come through. Obviously hitting it through the edges where the tongue and groove is is not a great place. And if it's dead center of the decking section between the rafters there's risk of splitting the wood. One roofer told me since they know the width of each piece and the location of the joists below they can mark out some kind of template for the underlayment and shingles so they'll always know about where they are.

Does this sound right? Perhaps with the new nail guns there's less hammering overall and less stress on the wood?

A. Spruce
Re: Roof Nailing

If you're worried about damage to the deck because it is visible from underneath, then overlay it with 1/2" plywood that is nailed directly into the rafters, then use a 1" nail roofing nail to attach the shingles, that way the nails won't even penetrate into the 1x decking at all.

That may sound strange, but if you measure the thickness of two shingles plus the paper you're at just about1/2", the plywood will make up the difference in nail length.

BTW, nailing the roof is a far better means of shingle attachment than to use staples.

dj1
Re: Roof Nailing

Spruce's advice is right on, but if you're on a budget and if your deck is in good condition, you don't need the extra plywood.

Just lay down 30 lb paper and use 1" roofing nails.

The difference between roofing nails and staples? wind resistance: nails can resist higher winds than staples. If your roofer insists on using staples (it saves him labor and time) offer him a little extra incentive.

BTW, roofing nails that go through the deck should not be of a great concern, so you can even use 1-1/4" nails. What you need to watch for though is that the paper has no cuts, no holes and lap tar is used where needed. If the roofer drives a nail in the wrong place, pulls it out and drives it in a different place, the hole must be plugged. To make sure, you must be able to supervise. Left unsupervised, roofers make a million mistakes.

A. Spruce
Re: Roof Nailing
dj1 wrote:

The difference between roofing nails and staples? wind resistance: nails can resist higher winds than staples. If your roofer insists on using staples (it saves him labor and time) offer him a little extra incentive.

The larger shank and head diameter makes all the difference, though it is worth noting that unless the fastener is driven properly, it is not going to hold anything. Therein lies the single biggest problem with staples, they are rarely driven to the proper depth, they are over driven, which means that they've cut most of the way through the shingle.

Fencepost
Re: Roof Nailing

Around here, inspectors REQUIRE the roofing nails to fully penetrate the sheathing. I think that's so they can see that they are long enough.

It sure is annoying when you have to work in the attic and you scratch your head on protruding nails.

It seems like nailguns result in less cracking than hand-nailing.

jkirk
Re: Roof Nailing

every house we do a complete overhaul on hte exterior typically gets a new roof, most of hte time they have tongue and groove boards for the sheathing so we strip off all the shingles then go over the boards with plywood to not only give a better nailing suface for the shingles but makes the roof flatter. this template thing the roofer is telling you about sounds like b.s.. ive never heard of that

in many regions the use of staples for fastening shingles does not meet code. they dont have the holding power of nails in high wind regions.. keep in mind the roof is the first line of defense against the weather for your house and is one of hte first things insurance companies look at when they go to approve your house for coverage. dont mess around with cheap labor

David
Re: Roof Nailing

Thanks very much for the input. Yes we always hire licensed, experienced and insured contractors. Though I did put in a question about staples, we wouldn't use them for all the reasons mentioned here.

David
Re: Roof Nailing

I misspoke; I wrote staples when I really meant a nail gun, which I understand is fairly easy to calibrate the pressure for so the nails don't go through the shingles. So nail gun is fine, yes?

dj1
Re: Roof Nailing

The thing is that you want to use 'roofing nails' and not staples. Roofing nails have large heads and hold a lot more of the shingles than staples. In numbers, nail heads are 14/32" wide while staples are only 1/32" wide. It's easy to see how nails hold more than a staples.

The use of a roofing nail gun is fine, as lond as it drives the nails correctly.

A. Spruce
Re: Roof Nailing

A roofing nail gun with the right length nail and that is adjusted to the correct pressure will be fine.

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