10 –
TANDEM
®
SYSTEM
BUILDING A RETAINING WALL
TYPICAL CROSS-SECTION AND INSTALLATION PATTERN –
LAFITT OR MELVILLE TANDEM 180 WALL
A Straight capping unit
90 mm × 305 mm × 400 mm
(3 9/16
"
× 12" × 15 3/4")
B Structural units
180 mm × 155 mm × variable (335, 402, or 469 mm)
7 1/16" × 6 1/8" × var (13 3/16", 15 13/16" or 18 1/2")
C Veneer units
180 mm × 67 mm × variable (335, 402, or 469 mm)
7 1/16" × 2 5/8" × var (13 3/16", 15 13/16" or 18 1/2")
D 100-mm perforated drain (4") connected to drains
E Geotextile membrane
F 0-20 mm (0-3/4") compacted aggregate base,
min . 300 mm (12")
G Min . buried depth of 150 mm (6")
H 20 mm (3/4") clean stone
I Starter unit
90 mm × 200 mm × 400 mm
(3 9/16" × 7 7/8" × 15 3/4")
INSTALLATION PATTERN
LINEAR PATTERN WITH LAFITT OR MELVILLE TANDEM 180 UNITS ONLY
A
B
H
E
D
G
I
F
C
300 mm
(12 in) min .
150 mm (6 in) min .
900 mm (36 in) max
300 mm (12 in) min .
0° or 9°