1961 steel joist - la series
 

1961 steel joist - la series
i need to check an existing steel joist roof built in 1961 for loads due to some new hvac equipment. the joists are designated as 40la18 and they span 68'-10". an old thread (
according to the sji 50 year joist digest, a 40la18 has a uniform load capacity of 632 plf for a clear opening or net span of 69 feet.
good luck!