Dimensions Guide

POLY-CLASSIC ROUND SHAFT SPECIFICATIONS
ROUND NON-TAPERED SHAFTS:
Standard FRP column shafts are the same height as the listed size. Tuscan caps and bases, and Attic
bases go around the shaft, and do not affect the overall height. Ornamental capitals are not typically
available for non-tapered round shafts.
Since the Tuscan caps for DuraS-
tone columns install on TOP of the
shaft, rather than around it, the
shaft itself is reduced in overall
height by the height of the Tuscan
cap. The height of the shaft plus
the height of the cap will achieve
the overall stated column height.
While all sizes of the non-tapered
shafts are considered straight,
there may be a small amount of
residual taper on the larger col-
umns. Rather than creating new
molds for the manufacturing proc-
ess, the 16” and larger diameter
columns are made using the
straight portion of our tapered
molds. (If the shaft is installed with
the residual taper at the bottom,
the base will almost completely
cover that taper.)
All non-tapered shafts may be
ordered fluted. Flutes typically end
1” from the cap and 1” from the
base. Fluting can be adjusted for
the customers requirements.
Column
Nominal
Diameter
Shaft
Height
Shaft Diameters*
Space Available Inside
Shaft:
Flute
Width
(24 ea.)
Outside
Diameter
Inside
Diameter
For
Round
Post
For
Square
Post
(A) (B) (C)
8”
8’
7 5/8” 6 3/4” 6 3/8” 4 1/2” 11/16”
10’
10”
8’
9 11/16” 8 3/8” 8” 5 5/8” 7/8”
10’
12”
8’
11/5/8” 10 3/4” 10 3/8” 7 5/16” 1” 10’
12’
14”
8’
13 1/2” 11 1/2” 11 1/8” 7 7/8” 1 5/16”
10’
12’
14’
16”
8’
15 7/16” 13 1/2” 13 1/8” 9 1/4” 1 1/2”
10’
18”
8’
17 3/8” 15” 14 5/8” 10 3/8” 1 11/16” 10’
11’
20”
8’
19 3/8” 18” 17 5/8” 12 1/2” 1 7/8” 10’
11’
24”
8’
23 3/8”
21 1/4”
(top ID)
20 7/8” 15” 2 5/16”
10’
12’
14’
15’
* Diameters may vary ± 1/8”
† Neck Height is the distance from the top of the shaft to the top of the astragal, ± 1/8”.
‡ Astragal height is only the ring portion, and does not include the fillet and cove.
Inside
Round
Top Diameter
Inside
Square
The “Space Available Inside Shaft” measurements
are calculated at the top inside diameter (with ±
3/8” tolerance), when using Tuscan or Roman
Doric caps. (Inside diameters may be reduced for
fluted columns.)
These measurements are provided to assist in
determining the correct column diameter to go
around a load bearing post or lally column, or for
clearance for water downspouts, conduits, etc.
Column Diameter Concentric Load Eccentric Load*
8” 10,000 lb. 6,600 lb.
10” 14,000 lb. 10,720 lb.
12” 18,000 lb. 13,200 lb.
14” 20,000 lb. 11,520 lb.
16” 20,000 lb. 13,200 lb.
18” 20,000 lb. 9,040 lb.
20” 20,000 lb. 18,960 lb.
24” 20,000 lb. 13,200 lb.
*See testing documentation for full information on eccen-
tric loading values.
LOAD CAPACITIES:
Round Non-tapered Column Shafts
(A)
(B)
(C)
(B)