Centre-to-centre distance

distance or ctc distance) is a concept for distances, also called on-center spacing (o.c.

spacing or oc spacing), heart distance, and pitch.

It is the distance between the centre (the heart) of a column and the centre (the heart) of another column.

By expressing a distance in c.t.c., one can measure distances between columns with different diameters without confusion.

This concept applies to other architectural features that may have variable diameters/widths and spacings, such as pillars or ceiling beams and baffles.