I have installed a sagging ceiling with a double 2x6 header. I have it resting on two jack studs on either end and it butts up against the wall stud. The ceiling joists are sitting on top of the new header but I'm trying to determine the best way to secure the header to the studs. 16d nails? Simpson Strong-Tie plates? Thanks....

My intention is to lay 1' x 2' tiles over a concrete basement floor. I thought I had a flat concrete floor but I've now found a high spot that rises up about 1/8" from the rest of the floor in a sort of slight hump. As I understand it, using a very straight board 10' long you should have no more than 1/4" gap anywhere. (Please correct me if I'm wrong on this.) [ATTACH]67318[/ATTACH] As seen in the image, with the hump in the middle I look okay, but the lower image shows I'm not. The floor looks pretty good everywhere else I check with my stud although there are some areas that have 1/8" valley. Can someone explain to me how to measure correctly? Thanks