Block piers

[wayne soper]

My brains not working and I can't find the height code for concrete block piers.
I'm remembering anything over three high requires double but can't find the section.
Thanks in advance, Wayne
Here's the reason for the question.

[Ted Menelly]

Ten times there least dimension

IRC 2000

R606.5 Piers

[Ted Menelly]

The unsupported height of masonry piers shall not exceed ten times there least dimension. When structural clay tile or hollow masonry units are used for isolated piers to support beams and girders, the cellular spaces shall be filled solidly with concrete or type M or S mortar, except that unfilled hollow units may be used if their unsupported height is not more than four times their least dimension. Where hollow masonry units are solidly filled with concrete or type M, S or N mortar the allowable compressive stress shall be permitted to be increased as provided in table R606.4

[wayne soper]

Thanks guys, These are not filled