HELP: T&G planking vs plywood?

A tree recently fell on my house and nearly crashed completely through it. The sheathing for the roof was originally tongue-and-groove planking (it’s a 1950’s brick ranch with a typical sloping roof, in NC). The contractors want to replace this sheathing with plywood (1/2" CDX) because the tongue-and-groove planking is “expensive” and “hard to get”. But I was assured that it is “just as good.”

Is it really just as good?

Thank you in advance!

You’re going to pay a boatload of money for tongue and groove sheathing. No CDX is not just as good in some senses, but it is definitely more practical. If I had to resheath my house, I would not use tongue and groove and I pride myself on doing it right. The sheathing is just something to nail the shingles to, tongue and groove is overkill. 1/2" disturbs me more than plywood, but building codes may be different where you live.

my insurance is covering everything, does that change your opinion?

and about the 1/2"… you think that’s too thin or too thick?

(thank you very much by the way)

the last time i checked tongue and groove is 1" thick.
you can replace with plywood.
not 1/2", but 1 "

use one 1" plywood.


i think its too thin, but building codes vary. Where I am, 3/4" is standard… are they going over an entire existing roof-deck? If that’s the case, 1/2" is standard. I think I’d charge 5x more just in labor for the tongue and groove… you think your insurance is goint to pay for THAT? I’m not sure myself, but…

hmmm, I’ll have to find out how to find out what the building code is here… I don’t know what a “roof-deck” is, but I certainly don’t have a deck and they are not going to replace the entire roof (except for the shingles)

my state farm guy (good guy) assured me as we were going through the house that “everything will be put back together as it was, except for instances where things need to be brought back up to code” and I made sure to get a response like that because I told him I was weary of new construction because my old stick-built house literally saved my life (it was very close) I have many more trees around me so the threat remains until I can cut a few down

thanks again!

roof deck just means the sheathing…

if they’re not replacing the whole roof, then they’re not going over it. That doesn’t comply to building codes where I live. Where you live might be different.

interesting, thank you very much

all tongue & groove in NY is 1" (actual size 3/4 ") what i would do is cut the broken boards back to the rafters, then take out the broken boards, and replace with 3/4 cdx. that is code in NY state with heavy snow loads…so i would assume that doing it in NC would be adequate.

what marshall ext. said :smiley:

thank you both! I’ll give updates tomorrow!


I would go back with the tounge and groove. More strutural integerity.


I would go back with the tounge and groove. More strutural integerity.[/quote]

i agree with you on principle, but it’s just so impractical. Nobody is ever going to see a return on this investment. Not the contractor. Not the homeowner, not a future buyer of the home.

I don’t know. My roofs don’t blow off. That much I can tell you. Never. Ever. It is a covering, not the framing.

Even though the roof as it was has lasted 50 years, without a flaw and now part of it is going to be replaced with something that surely will not last that long?


If you are not using full sheets of plywood.

Replace with like kind.

I use a fair amount of Tounge and Groove in a year. If there had not been tounge and groove on the building, We would have had to resheet a lot of the house. Plywood does not hold the same.

Every hole you make in plywood weakens it. Not so with tounge and groove.

thank you Lefty

I’ve talked to my State Farm guy and he said that everything must be replaced with “like” and of the same quality and if the contractors cannot get a hold of “like” materials then they are to use an “exceptable substutitute” which the local building codes obviously recognize plywood as being. He is convinced that plywood, because it will span 6 rafters or so, will be just as strong as the T&G…

However, Someone on another forum recomended the the possibility of simply replacing the broken T&G planks with 1x?* pine planks. My SF guy is checking into that. Have any of you people done that or heard of doing that?

  • “?” being whatever the width is of the T&G now

Is there some kind of definitive resource that I can go to that will tell me the difference between building materials like plywood vs. plank, a resource that the contractors will recognize that will help to back me up when everyone tells me that plywood will be just as strong as plank?

Issue resolved.

My insurance guy has no problem about covering T&G planking. I met the project manager onsite today and after convincing him that I knew plywood was not of equal value/strength/etc. he said that’s fine he’ll do it. It just may take a while because they know of people who CAN make it, but I guess don’t ACTIVELY make it and have it in stock. I told them if it takes longer, that’s ok.

My thinking is that I know the house (my first one) saved my life because of how it was built and the materials used, so no matter what, I do not want it put back together any weaker than it was.

Thank you everyone. And I’d recomend State Farm to anyone (as it was recomended to me).

I just didn’t think the insurance would really replace with all of that extra cost, good job. No State Farm Insurance here in Massachusetts. No Geico either. Insurance is heavily regulated here.