Diagonal Layout From The Center Of The Room
From the centre point, measure 4 feet down in each direction on lines X and Y, which you have already determined by the method described above.
From each of these points, measure 4 feet and scribe an arc. The conjunction of these arcs creates points D and E.
Snap a chalk line between points D and E, and the center point. This line represents a 45 degree angle.


