I usually post over on Knots, but was recently surprised when I built a new shop. I used 3/4″ tongue and groove Sturdi Floor plywood for the floor, and I was somewhat taken aback when I discovered that the tongue is cut from the 48 inch width, leaving a true coverage of only 47 and 1/2 inch. Of course, I discovered this after I had framed up everything based on 48 inch coverage. My shop was not so large that I couldn’t recover, but I was really disappointed. Is this normal of most T&G plywood flooring?
Woody
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I don't remember what the actual dimensions of the plywood were when I built my house 7 years ago, but I do remember that the local lumber yard sent two different brands of plywood for my order. Seems they switched distributors. The two plywoods were 1/2 inch different in their widths! Of course I didn't notice this until I had used up the top of the bundle and reached the "new" stock. And the switch had to happen in the middle of a row.... wasn't much fun tearing off the 3 sheets that I had already glued and nailed down with ring shank nails. Lumber yard replaced the 3 sheets and gave me excellant service after that!
Larry
PS I used to be NevadaLarry until I was banned for posting a questionable link to a "Concentration Test"....
I bought what I was told was the top-of-the-line brand, and it really did disappoint me. That could really create havoc in a major project when you have to stay on your 16 inch spacings, I would think. I was fortunate that I could adjust and live with it.
Woody
Yes, I think they are all that way.
That could really create havoc in a major project when you have to stay on your 16 inch spacings, I would think.
Ummmm, now you are scaring me. You did run the 8' length of the sheet perpendicular to the floor joists, yes ? The subfloor is not designed to be installed parallel with the joists, which is the only way you could install it where the 16 inch centers could affect your sheet layout.
Old homes that have odd joist spacing just require you to cut the 8' length of the sheets to match up.carpenter in transition
Yes, I ran them perpendicular, and this was fine. I had installed some cross bracing where the heavy shop tools would set and had to redo a couple of these, plus I came up a couple of inches short on the far side. I was able to cover this with the sill plates, but in a larger structure this could become a problem if you didn't plan for it. Silly me, I thought 4x8 plywood was still 4x8.
Woody
but in a larger structure this could become a problem if you didn't plan for it
I guess, maybe.
Under the wall plates you can just fill in with ripped scrap. The T&G edge isn't critical under a wall plate.
carpenter in transition
I think it works out that way because they mill the tongue and groove AFTER the sheet is cut to 4X8.
It can be annoying if you're not expecting it, as you found out. But unless a building width is an exactly multiple of 4', it really doesn't matter.
This seems to be getting more common. It is also more common that the flooring is not squared up. I think if you do not insist on putting it together too tightly it will work better. If the floor gets wet, especially, and you do not force it too tightly, it will be vrey close to 48"
Additionally, if you use engineered joists, you may find the 2 1/4" width to be quite helpful. Leaving a small gap on the short end of the flooring is no problem when you are not confined to a 1 1/2" width of, say, 2X10.
Having said all that, I prefer squared flooring with standard dimensions. The trick is, as with windows and other components, to measure before you start installing. Things are more variable than ever before.
I recently installed a french door. I ordered the door and prepared to frame up for it. I was going to do the rough opening per the rough opening instructions on my invoice. Since there was a similar door in stock in the five foot version, I measured it and came up with a different dimension. I added 1/2" to the height just to be safe. I figured it would be easier to install and extra piece of 1/2" OSB in the opening if the door actually matched up to the one in the store or to the dimensions on the invoice.
When I actually installed the door, it barely fit in the opening. Go figure.