Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Q: Flatness Tolerances for Residenti

[Subject Prev][Subject Next][Thread Prev][Thread Next]
As Harold noted, the requirements for flatness are whatever are in the project specifications.  If there is nothing in the project specifications, it will be hard, if not impossible, to enforce anything.

This is what is in Masterspec.  Project specifications would normally include either item 2 or item 3 and then specify required values, depending on the intended use of the structure.  Residential structures are very seldom done with F values although sometimes you see it in specs, usually because the specifier copied the specs from an industrial building.

****************************
2. Finish surfaces to the following tolerances, measured within 24 hours according to ASTM E 1155/E 1155M for a randomly trafficked floor surface:
a. Specified overall values of flatness, F(F) 25; and levelness, F(L) 20; with minimum local values of flatness, F(F) 17; and levelness, F(L) 15.
b. Specified overall values of flatness, F(F) 35; and levelness, F(L) 25; with minimum local values of flatness, F(F) 24; and levelness, F(L) 17; for slabs-on-grade.
c. Specified overall values of flatness, F(F) 30; and levelness, F(L) 20; with minimum local values of flatness, F(F) 24; and levelness, F(L) 15; for suspended slabs.
d. Specified overall values of flatness, F(F) 45; and levelness, F(L) 35; with minimum local values of flatness, F(F) 30; and levelness, F(L) 24.

3. Finish and measure surface so gap at any point between concrete surface and an unleveled freestanding 10-foot- (3.05-m-) long straightedge, resting on two high spots and placed anywhere on the surface, does not exceed the following:
a. 1/4 inch (6.4 mm).
b. 3/16 inch (4.8 mm).
c. 1/8 inch (3.2 mm).

************************

Gail Kelley