Floor Tile and Chalk Lines

Before starting any floor tile job, whether the tile is carpet, ceramic, or self-stick, you are supposed to snap a few chalk lines: From corner to corner, there will be one center point where the two lines intersect; from width to width and from length to length of the room, there will be a second point of intersection, which, in a perfectly square or rectangular room, will be at the same point. But let's say that the two center points don't overlap. How do you determine on which point to start tiling?

WHen using tile, you may need to shift the pattern a bit from the middle...the goal should be to minimize small slivers of tile, boards, etc. at the edges. It looks much better to have nearly full tile all around. Then, if you are going to do something like have a boarder, it can get more complicated. With tile, you also have the option of selecting your grout line to take up a small amount. If the room is not rectangular, small slivers will look worse, as the taper will become more apparent. You may need to shift L-R, or End to End to achieve that. So, the answer is, it depends. Also, keep in mind that with tile, unless it is rectified, it can vary from piece-to-piece and box-to-box not only in size, but color. So, it's good to be drawing from multiple boxes when laying, to randomize things.

You measure to the center of the walls, THEN compute the "number" of tiles to the walls in both directions from that center point. IF that leaves you with less than 1/2 a tile along the edges, then you offset the starting point one half tile width either way, which will then leave you with almost a full tile along the edges. Do NOT worry about diagonals.

Seems that if the diagonals cross at a different point, the walls are not 90º to each other all the way around. You will just have to deal with some uneven cuts

Thanks to all who responded!!

If the walls are parallel, regardless of the corner angles, the diagonals will cross in the center, but that does nothing to help you lay out the lines for starting your tiling.