Wood shingle replace sheathing thickness

Specific Inspection Topics Roofing Inspections
1

Tearing an old comp and a wood shingle roof off, going back with comp. Wood shingles are nailed to spaced 1x4s. I want to leave the 1x4s there thinking that it’s easier to install sheathing over them rather than lining up with rafters, using H-clips, etc.

IDK if it’s cheaper, but does code allow additional 1x4s to fill in between my old wood shingle roof’s spaced 1x4s and skip the new CDX? It looks like a tight fit.

Prolly not. How about reducing the CDX thickness because it goes over the spaced 1x4s? Is it OK to not worry about lining the CDX up with the rafters (as if there are no 1x4s) since I’m nailing into the 1x4s and they provide more support than rafters?

2

Part of the CDX thickness is to accept the shingle nail adequately.

3 Likes
3

As long as you have no gaps, it could work to use the 1x4’s for sheathing. But keep in mind you may have whole rows of shingle nails that land at a seam. The chance of it is high with 1X4 planking obviously. Now if it were 1X8 or 1X10 planks with no gaps, no problem.

1 Like
4

If I use longer nails to catch the 1x4s as well? So, yeah, prolly not worth it. Thx.

5

I know I’m older and don’t keep up with younger generation “slang”, but what is “prolly” and do inspectors use it in their reporting these days?

6

I did the same thing at my house several years ago. I went with half inch plywood over the wood planks, but attached/nailed to the rafters. I wouldn’t rely on the wood planks alone to secure the plywood. If you’re replacing wood shakes with spaced wood planks I’m guessing you’re home may be at least a hundred years old, so are the wood planks, probably a little soft.

The 3-tab shingles I used lasted 25 years and I replaced them about 3 years ago with architectural shingles. The roof decking has held up quite well.

2 Likes
7

probably

Prolly shouldn’t.

5 Likes
8

I’ve had lots of experience inspecting older houses that had wood shingles and I’d advise against in-filling between the skip sheathing. I asked this exact question at a CE conference once and the (very experienced) roofer explained that all the edges are a nightmare during expansion/contraction. Basically, seams/joints are the enemy of tar paper or other underlayment as it can and will get pinched and tear. I’ve probably seen a few thousand roofs with skip sheathing covered by plywood and only one done with in-fill (that’s what prompted me to ask the question). The standard install is to just go over the skip sheathing with the new decking.

5 Likes
9

Surprised that “professionals” use that at anytime. But I’m old school and appreciate “good” grammar… but it’s just me… :shushing_face: :wink:

10

Read some posts over. You’d be surprised…maybe. :man_shrugging:

11

Wow, I thought grammar Nazis went out of style years ago. I was even guilty many times back then. Kinda ironic, huh? Literally, I was a professional writer for many years. Hundreds of clients, Fortune 500 companies, billionaires, blah, blah. Even retired, I still write a few thousand words most days. But yeah, I get to use slang now, since no one’s paying me. Hadn’t ever thought that someone might want to tattoo my arm for it though. I do know how to google the meanings of words, so I guess one is as old as they feel.

1 Like
12

Thanks, everyone. I’ll put new sheathing over the 1x4s, unless they’re rotted out. Just easier than pulling up all of them, and easier to walk around on the roof - I’m an old man.

1 Like
13

Is that radiant barrier sheathing worth the extra dollars? Does it install the same way?

14

No. And a good thing. The posts here are informal and you are not an inspector writing reports for clients, so no problem with casual grammar. I use slang here sometimes, but never in a report. The deterioration of grammar is a topic for another thread, but we won’t solve it on this forum. Inspectors should use their best grammar in their reports.

Could be. In areas with extremes in heat or cold, it can be “worth it.” There are several different radiant barrier systems and sheathing, but some install like standard sheathing. If you plan to stay in your home for 10+ years, then you should consider it. In my experience, radiant barrier sheathing does not add value, so you only do it to save some energy costs. There are other considerations when trying to calculate how much savings you will get with one of these radiant barrier systems, but they can be effective. The wrong system for some houses, can be worse than none.

1 Like
15

Prolly not!

16

some prolly do…

1 Like
17

You’re prolly right.

19

This :point_up_2::point_up_2::point_up_2:.

@rlewis39 Since you didn’t say where you are located, I would add to check with some local roofing companies to see what sheathing and fasteners are required in your area. Around here, 1/2" OSB is used on single family homes instead of CDX plywood. It’s considerably more cost effective.
You should check with your local municipality to see if a permit is required for such a project as well.

3 Likes
20

Thanks for all the great info, guys.

I understand that I’m not an inspector and am somewhat intruding in y’all’s community. I appreciate that most of you have welcomed me, and I will try not to abuse your friendship. There are online forums for all the trades that I wish I knew (electricians, framers, plumbers, etc.), and I was searching for them when I found NACHI. I stopped because y’all are it.

Reminds of the old tire commercial - “where the rubber meets the road.” Those other forums have rubber, I have a road, and y’all are where they meet, and that’s what I want to know.

Not casting aspersions, but City Inspectors are fearsome and have historically had corruption issues. I’m surprised there aren’t a lot of homeowner Karen vs City Inspector vids online, with the homeowners losing every time. I’ve already had a run-in with such inspector corruption here in Houston, albeit not related to construction. I’m just saying that I’d rather have inspectors telling me what to do than listen to tradesmen and find out an inspector disagrees later. So, when I found this forum, I was excited, but decided I should tread lightly by asking general questions and not specific construction advice.

I wouldn’t have been surprised had I been shunned as an outsider. I was surprised by the Nazi. Trust me, y’all don’t even know what it’s like to live that life, just as I don’t know what inspectors go through. I began in a corporate Marketing department. A Fortune 500 company with more than 50k employees. Every word I wrote, and I wrote hundreds of thousands, was reviewed by 8 other writers, our CMO, any other senior execs who oversaw the article topic, and of course, those 50k employees. I guarantee you that everyone one of them had ‘suggestions,’ and no grammar mistake made it through unnoticed.

I’m retired now, and not as sharp or patient as I used to be, so I don’t try to meet those standards, but old habits die hard. The one indulgence I do allow myself is an expanded vocabulary. Corporate-speak is brain-numbing, and if I have a talent in this field exceeding others’, it is creativity. So, excuse me if I’m informal at times. When y’all retire, I’ll cut you slack as well.

Except the Nazi. He better be perfect. I can’t even imagine the self-esteem that allows someone to criticize word usage as bad grammar, much less to actually make that false claim in a post consisting of two incomplete sentences and multiple grammar mistakes. We’re witnessing a character flaw, and it ain’t pretty. But, it’s water off this duck’s back.

On to my questions…

1 Like
21

I live in Houston, so no weather extremes, or at least not by Texas standards, lol. A lot of the state gets real hot for long stretches. Houston isn’t as bad being nearer the coast. We do have humidity issues though. Sounds like radiant barrier sheathing would cost me another $500 over standard OSB, and I’ll die in this house, and that will prolly be more than 10 years from now, but who knows. I may opt for the radiant barrier.

And, yes, I will be asking contractors, tradesmen, and the City many of these questions. I just hate going into such conversations without base knowledge. Same issue as taking my car to a mechanic without knowing what’s wrong with it. I have 4 non-running cars now because I refuse to do that. (I have a lot of cars.)

I’m definitely not a tradesman of any skill, but did work as a roofer through college, and much of that hasn’t changed. I’ve also remodeled many houses and, importantly, know when I’m in over my head. I’m just planning now, planning how to make a plan.

OSB sounds good. IDK the difference and just saw the CDX reference somewhere. With the 1x4s underneath, I expect strength won’t be an issue.

Thanks, everyone.