[Marco]

All of the observations and opinions are absolutely correct. OSB is inferior to plywood and the difference in price to quality again greatly favors plywood, 23/32 OSB $38, 23/32 plywood $40. If you had a both a sheet of OSB and plywood nailed to the floor and took 3 to 5 swings of the hammer to each, the OSB would have a hole in it and the plywood would not.

 

[Marco]

Hope it didn't rain before they had the OSB covered. The 23/32 could be closer to 28/32 but it would provide a softer landing if you fell on it assuming you didn't fall through. OSB is second to plywood as particle board is to OSB. They use to put particle board down for flooring that idea as well as the floor didn't last long.

 

[Marco]

I wish I had taken pictures of the floor I put down in a cabin in Canada. It was about 20 years ago and I was replacing a floor that was put in 50 years prior to that. The original sub floor was solid pine that I replaced with 3/4" OSB. The original sub floor was about 6" off the dirt ground. I hand dug the dirt to a depth of 4 feet thinking that would be fine. I was wrong within a few years mold started growing on the OSB and 10 years later the floor was completely rotted and had to be replaced again. The original floor that was still in place in the front of the cabin is still as solid as the day it was put down in 1939. That part of the floor had an air space of at least 3 feet. So air space caused the original floor to rot but even with 4 feet of air space the cheap OSB rotted.

23/32 OSB 80 pounds, 23/32 plywood 60 pounds. That is 20 pounds of extra glue spread over 32 square feet. You need all of that glue to get the thousands of thin strands of wood to stick together. OSB is here to stay because of the cost. A quick search shows a 5 dollar difference in sheathing 7/16 OSB, 1/2" Plywood. 5 dollars per sheet on all of your exterior walls and roof adds up. Adds up for the builder. For my smallish house roughly 1100 square feet the extra cost would be $660. If builders presented the cost difference between the 2 sheathings I would pick plywood. What happens when the roof leaks or the vinyl siding has a crack or void and water penetrates? Then there's your flooring substrate, same thing. My ice maker leaked the dishwasher leaked the water heater leaked a pipe busted, when the water hits OSB it's a major costly problem.