Gee Jim, what happened to putting a hole in the top half of the joist is like removing a brick from a stack of bricks? Glad to see you came around on this issue. As far as Ron's 6 inch hole is concerned, being that it is only 18 inches from the end of the joist, I agree he has little to be concerned about. On the issue of horizontal shear stress, if you say it is zero at the center of the joist, then why aren't 2 2x4s laid flat on top of each other (for example) just as strong in bending before they are nailed together as they are after? In fact, instead of being only twice as strong as one, they are 8 times as strong. The forces keeping them from moving relative to each other at the middle result in HORIZONTAL SHEAR STRESSES and they are at a maximun at the middle, not zero.