26 –
TANDEM
®
SYSTEM
A
G
F
H
E
B
C
D
C
D
BUILDING STAIRS
OPTION 2
90 mm (3 9/16")
90 mm (3 9/16")
400 mm (15 3/4")
A
G
F
H
E
B
C
C
D
D
OPTION 1
400 mm (15 3/4")
90 mm (3 9/16")
90 mm (3 9/16")
25 mm (1")
LAFITT TANDEM STEP UNITS
To build stairs, it is recommended that the step unit be used in
combination with one of the following options for the riser:
A Lafitt Tandem step unit
90 mm × 400 mm × 400 mm
(3 9/16" × 15 3/4" × 15 3/4")
B
Option 1
Structural unit and Laffit Tandem veneer
90 mm × 222 mm × variable
(3 9/16" × 8 3/4" × variable)
Option 2
Lafitt Tandem straight capping unit
90 mm × 305 mm × 400 mm
(3 9/16" × 12" × 15 3/4")
C Concrete paver
60 mm (2 3/8") or 80 mm (3 1/8
"
)
D 25 mm (1") bedding sand
E 0-20 mm (0-3/4") compacted aggregate base
F Existing soil
G Geotextile membrane
H Starter unit 90 mm × 200 mm × 400 mm
(3 9/16" × 7 7/8" × 15 3/4")
All step and riser units must be glued together
using Permapro adhesive .