work off of the top one if its possible..... if the ridge is offset from the eave then tack a 1x4 on the ridge and let it overhang so you can run your tape straight from the 1x4 to the eave. I usually put my first row on because it is usually an inch or so different from the remaing field... monier tile I believe you measure 14" from the eave to the top of the 1x4 but consecutive courses should be no more than 13.5". I also measure to a point 1.5" down from the ridge to allow for the tile lugs and the 2x3 or 2x4 ridge nailer.
If you go to a lower ridge first you may end up with a cut tile at the top ridge.... also... do not try and gauge to one ridge then after you reach it gauge to the next ridge because it makes the keyline look like crap..... i would rather cut the half tile if that is the case.
Also a little trick for you once you put your first field batton on cut a few 1x2's EXACTLY the same size as the gap between the first 1x4 and the 2nd one...... you can now use these instead of a tape and its more accurate because the board can not slide down while you are holding it. Always measure a batton in 3 places (end, mid, end) to keep your lines straight. I cannot stress enough how exact these need to be... if you are 1/16th off..... it will be 1" off when you get to the top of a 16 line roof.
Ken
