RE: DATACENTER: Rack spacing

[Sean Donelan <SEAN@SDG.DRA.COM>]

Without knowing the specific rack sizes, equipment sizes, floor loads,
heat loads, etc; you can only do SWAG.

A few different sources for center-to-center rack spacing.

NEBS planning requirements use alternating wide and narrow aisles.  And
different layouts depending on the equipment such as either 4 wide racks
per 20ft, or 6 narrow racks per 20ft.

   Narrow spacing: alternating 3'(ft) and 2'(ft)6"(in) rack spacing.
   Wide spacing:   alternating 5'(ft) and 3'(ft) rack spacing.

BICSI planning guidelines call for uniform 64"(in) rack spacing.  I don't
think the TIA/EIA standards directly address this subject.

I don't have ready access to them, but there are also some metric
guidelines from Canada(CSA) and Europe(ETSI).  They are essentially
the same as those above.  The basic difference: the measurements are
in "whole" metric measurements, e.g. 1meter instead of 3feet.

I start out trying to use 66"(in) spacing for older buildings, and
78"(in) for new buildings that may need to be ADA compliant.  Or a
combination of wide and narrow aisles when the aisles need to be
coordinated with tiles of a raised floor (60-78 inches). But some piece
of equipment or a building column always seems to throw things off, so
I usually don't end up with perfect spacing.  Some aisles get a bit
wider.  But usually they end up a bit narrower.

Once again, the specifics are determined by the equipment requirements
(make sure swinging doors have enough room to completely open) and the
owner's desires.  There may also be some other building code requirements
that have to be considered, e.g. extra clearances around electric panelboards
or DC switchboards.

But I'm not in the co-locate business, and don't rent out the space by
the square inch.  So I don't try to fit/cram as many racks into the
smallest space possible.
-- 
Sean Donelan, Data Research Associates, Inc, St. Louis, MO
  Affiliation given for identification not representation