Jon_E
Well-known member
Did a little research, and an article from 1997 on Journal of Light Construction Online mentions a book called Handbook of Construction Tolerances, which lists a bunch of suggested tolerances for various phases of construction.
Quote: "According to the Handbook , horizontal building layout (including the foundation) involves both dimensional accuracy and squareness. For measurements less than 10 feet, the tolerance is 1/8 inch; between 10 and 100 feet, it’s 1/4 inch. For squareness, the tolerance for the dimension of the 5-leg in a 3-4-5 triangle measured with a steel tape is 3/4 inch in 100 feet. Use the same ratio for diagonals of less than 100 feet. For example, when measuring a 50-foot diagonal, the acceptable tolerance would be 3/8 inch (one-half the tolerance for the 100-foot diagonal).
Foundations walls should be level within 1/4 inch in 10 feet, while the entire foundation should be level within 1/2 inch."
So while you have a majority opinion stating that it's not too bad, and indeed it can be fixed with framing, the actual workmanship really isn't too great. I specified that my house and garage foundations meet a 1/4" tolerance for squareness, and they do.
Quote: "According to the Handbook , horizontal building layout (including the foundation) involves both dimensional accuracy and squareness. For measurements less than 10 feet, the tolerance is 1/8 inch; between 10 and 100 feet, it’s 1/4 inch. For squareness, the tolerance for the dimension of the 5-leg in a 3-4-5 triangle measured with a steel tape is 3/4 inch in 100 feet. Use the same ratio for diagonals of less than 100 feet. For example, when measuring a 50-foot diagonal, the acceptable tolerance would be 3/8 inch (one-half the tolerance for the 100-foot diagonal).
Foundations walls should be level within 1/4 inch in 10 feet, while the entire foundation should be level within 1/2 inch."
So while you have a majority opinion stating that it's not too bad, and indeed it can be fixed with framing, the actual workmanship really isn't too great. I specified that my house and garage foundations meet a 1/4" tolerance for squareness, and they do.