Permacon TANDEM SYSTEM 2015 User manual

INSTALLATION GUIDE
TANDEM®SYSTEM
2015

TANDEM®SYSTEM
INDEX
SYSTEM DESCRIPTION 4
VENEER UNITS AND STRUCTURAL UNITS...........4
CAPPING UNIT, STEP UNIT AND STARTER UNIT ......5
TANDEM UNIT ASSEMBLY ......................6
BUILDING A RETAINING WALL 7
STARTER UNIT ..............................7
PRE-ASSEMBLY OF UNITS ......................7
ANCHOR SYSTEM ............................8
TYPICAL CROSS SECTION
AND INSTALLATION PATTERN ...................9
STRAIGHT WALLS ...........................13
CURVED WALLS.............................13
90° CORNER WALL ..........................13
RETAINING WALL CAPPING ....................17
BUILDING A DOUBLE-SIDED WALL 18
DOUBLE-SIDED TANDEM UNIT ASSEMBLY..........18
STARTER UNIT .............................18
STRAIGHT WALLS ...........................19
CURVED WALLS.............................22
END OF A WALL.............................23
90° CORNER WALL ..........................24
DOUBLE-SIDED WALL CAPPING .................24
BUILDING STAIRS 25
MELVILLE TANDEM STEPS ....................25
LAFITT TANDEM STEPS ......................26
ESPLANADE TANDEM STEPS ...................27
BUILDING PILLARS 28
TANDEM PILLARS WITH PILLAR GRID ............28
TANDEM PILLAR WITH STRUCTURAL UNITS .......36
CONSTRUCTION OF OUTDOOR
LIVING COMPONENTS 40
GENERALITY ...............................40
OUTDOOR GAS FIREPLACE ....................52
OUTDOOR KITCHEN (BBQ, REFRIGERATOR, BAR) ....53
PATIO FURNITURE (BENCH AND TABLE) ..........54
PRIVACY WALLS AND FENCES ..................55
DECK SKIRTING ............................61
TANDEM SYSTEM®–3

90 mm LAFITT VENEER UNITS
180 mm STRUCTURAL UNITS
180 mm LAFITT VENEER UNITS
90 mm STRUCTURAL UNITS
A – 90 mm VENEER UNIT
90 mm × 67 mm × 201 mm
3 9/16" × 2 5/8" × 7 7/8"
C – 90 mm VENEER UNIT
90 mm × 67 mm × 335mm
3 9/16" × 2 5/8" × 13 3/16"
E – 180 mm STRUCTURAL UNIT
180 mm × 155 mm × 335 mm
7 1/16" × 6 1/8" × 13 3/16"
G – 180 mm STRUCTURAL UNIT
180 mm × 155 mm × 469 mm
7 1/16" × 6 1/8" × 18 1/2"
E – 180 mm VENEER UNIT
180 mm × 67 mm × 335 mm
7 1/16" × 2 5/8" × 13 3/16"
G – 180 mm VENEER UNIT
180 mm × 67 mm × 469 mm
7 1/16" × 2 5/8" × 18 1/2"
A – 90 mm STRUCTURAL UNIT
90 mm × 155 mm × 201 mm
3 9/16" × 6 1/8" × 7 7/8"
C – 90 mm STRUCTURAL UNIT
90 mm × 155 mm × 335 mm
3 9/16" × 6 1/8" × 13 3/16"
B – 90 mm VENEER UNIT
90 mm × 67 mm × 268 mm
3 9/16" × 2 5/8" × 10 1/2"
D – 90 mm VENEER UNIT
90 mm × 67 mm × 402 mm
3 9/16" × 2 5/8" × 15 13/16"
F – 180 mm STRUCTURAL UNIT
180 mm × 155 mm × 402 mm
7 1/16" × 6 1/8" × 15 13/16"
F – 180 mm VENEER UNIT
180 mm × 67 mm × 402 mm
7 1/16" × 2 5/8" × 15 13/16"
B – 90 mm STRUCTURAL UNIT
90 mm × 155 mm × 268 mm
3 9/16" × 6 1/8" × 10 1/2"
D – 90 mm STRUCTURAL UNIT
90 mm × 155 mm × 402 mm
3 9/16" × 6 1/8" × 15 13/16"
180 mm ESPLANADE VENEER UNITS
E – 180 mm VENEER UNIT
180 mm × 60 mm × 350 mm
7 1/16" × 2 3/8" × 13 3/4"
G – 180 mm VENEER UNIT
180 mm × 60 mm × 562 mm
7 1/16" × 2 3/8" × 22 1/8"
F – 180 mm VENEER UNIT
180 mm × 60 mm × 495 mm
7 1/16" × 2 3/8" × 19 1/2"
DESCRIPTION
LAFITT TANDEM
STRAIGHT CAPPING UNIT
90 mm × 305 mm × 400 mm
3 9/16" × 12" × 15 3/4"
MELVILLE TANDEM
STRAIGHT CAPPING UNIT
60 mm × 305 mm × 600 mm
2 3/8" × 12" × 23 5/8"
STARTER UNIT
90 mm × 200 mm × 400 mm
3 9/16" × 7 7/8" × 15 3/4"
LAFITT TANDEM STEP UNIT
90 mm × 400 mm × 400 mm
3 9/16" × 15 3/4" × 15 3/4"
MELVILLE TANDEM STEP UNIT
60 mm × 400 mm × 600 mm
2 3/8" × 15 3/4" × 23 5/8"
OTHERS UNITS (SOLD SEPARATELY)
4–TANDEM®SYSTEM
90 mm MELVILLE VENEER UNITS 180 mm MELVILLE VENEER UNITS
A – 90 mm VENEER UNIT
90 mm × 67 mm × 201 mm
3 9/16" × 2 5/8" × 7 7/8"
C – 90 mm VENEER UNIT
90 mm × 67 mm × 335 mm
3 9/16" × 2 5/8" × 13 3/16"
E – 180 mm VENEER UNIT
180 mm × 67 mm × 335 mm
7 1/16" × 2 5/8" × 13 3/16"
G – 180 mm VENEER UNIT
180 mm × 67 mm × 469 mm
7 1/16" × 2 5/8" × 18 1/2"
B – 90 mm VENEER UNIT
90 mm × 67 mm × 268 mm
3 9/16" × 2 5/8" × 10 1/2"
D – 90 mm VENEER UNIT
90 mm × 67 mm × 402 mm
3 9/16" × 2 5/8" × 15 13/16"
F – 180 mm VENEER UNIT
180 mm × 67 mm × 402 mm
7 1/16" × 2 5/8" × 15 13/16"

DESCRIPTION
ESPLANADE CHISELED CAPPING UNIT
60 mm × 381 mm × 1067 mm
2 3/8" × 15" × 42"
ESPLANADE PILLAR CAPPING MODULE 25 × 25
60 mm × 635 mm × 635 mm
2 3/8" × 25" × 25"
ESPLANADE PILLAR CAPPING MODULE 27 × 27
60 mm × 686 mm × 686 mm
2 3/8" × 27" × 27"
ESPLANADE PILLAR CAPPING MODULE 29 × 29
75 mm × 737 mm × 737 mm
3" × 29" × 29"
ESPLANADE PILLAR CAPPING MODULE 31 × 31
75 mm × 787 mm × 787 mm
3" × 31" × 31"
SETBACK ANCHOR
CORNER CONNECTOR
TANDEM SHELF ANGLE 8'
64 mm × 64 mm × 2439 mm
2 1/2" × 2 1/2" × 8'
SCREW
#10 × 1 1/4"
SCREW
#10 × 3 1/2"
TANDEM GRID
CONNECTOR
TANDEM GRID
PILLAR KIT
TANDEM MODULAR GRID
720 mm × 1080 mm
28 3/8" × 42 1/2"
DOUBLE SIDED
CONNECTOR
ANCHORS AND CONNECTORS OTHERS
OTHERS UNITS (SOLD SEPARATELY)
TANDEM SYSTEM®–5
BRACKETS
(LOOP CLAMPS)
Note: Each Tandem Grid Pillar Kit comes with 1 bag of 200 Tandem Grid Connectors.
Each Tandem Modular Grid comes with 1 bag of 60 Tandem Grid Connectors,
10 screws #10 × 1 1/4 " and 10 loop clamps.

DESCRIPTION
6–TANDEM®SYSTEM
TANDEM UNIT ASSEMBLY
Tandem units come in 2 heights: 90 and 180 mm (3 9/16"and 7 1/16").
For each structural unit, there is a veneer unit of the same length and height.
The unit can be assembled using the dovetail joint (an interlocking male/
female system). Each structural unit has two vertical tenons (male side)
and each veneer unit has at least two mortises (female side). The veneer
units are joined to the structural units by simply sliding the mortises into
the tenons to create the Tandem unit. Today, there are three types of veneer
units; Lafitt, Melville and Esplanade Tandem units. The total depth of the
Lafitt and Melville Tandem unit is 222 mm (8 3/4"); for the Esplanade
Tandem unit, it is 233 mm (9 1/8").
Attention: in general, do not overlap two veneer units on a single
structural unit of the same height, and do not overlap two structural
units on a single veneer unit. Do not install two 90 mm veneer units
on a 180 mm structural unit.
LAFITT TANDEM UNIT
ESPLANADE TANDEM UNIT
Structural unit
Structural unit
Lafitt Tandem
veneer unit
Esplanade Tandem
veneer unit

STARTER UNIT
200 mm
400 mm
TANDEM®SYSTEM –7
R = 36"
STARTER UNIT
The first course of the Tandem wall is built using the Tandem
wall starter unit. This is to be installed directly on the granular
base foundation and levelled. The unit is bevelled to make it
easy to install curved walls.
The use of starter units is strongly recommended given that the
Tandem units (structural and veneer units) can then be placed
on a uniform base ensuring overall wall stability.
CURVED INSTALLATION
(PLAN VIEW)
STRAIGHT INSTALLATION
(PLAN VIEW)
BUILDING A
RETAINING WALL
PRE-ASSEMBLY OF 90 UNITS
It is best to pre-assemble veneer and structural units before
beginning to stack them in building the wall.
Once pre-assembled, Tandem units are randomly installed on
starter units, using the four different sizes.
PRE-ASSEMBLY OF 180 UNITS
Because the Tandem System 180 components are heavier,
we recommend that you install the structural units first,
then attach their veneer units.
Recommended handling for the Tandem 90 unit
Structural unit
Veneer unit
Tandem unit

8–TANDEM®SYSTEM
ANCHOR SYSTEM
The way in which the setback anchor is positioned in the Tandem wall
system determines the slope of the wall. This positioning is what allows
for either vertical or sloped walls.
Generally, at least one setback anchor must be installed per
Tandem 90 unit, with two setback anchors for the Tandem 180 unit,
to make sure the wall is stable. Setback anchors come with or without
blades. No-blade setback anchors are used in curved walls. Both types
of anchor can be used in straight walls.
Allowable heights(1): 650 mm (26 in) without a slope (0°, vertical);
1.050 mm (42 in) with a slope of 9°
Note: For a 9° of slope, the setback per row of 90 mm (3 9/16")
is 14 mm (9/16") and the setback per row of 180 mm
is 28 mm (1 1/8")
(1) Maximum height of the wall including the buried portion of 150 mm (6 in)
without additional load or embankment above the wall.
There are several ways to build a Tandem retaining wall:
Using only Lafitt and Melville Tandem 90 units
Using only Lafitt and Melville Tandem 180 units
Combining Lafitt and Melville Tandem 90 and 180 units in a single wall
Using only Esplanade Tandem 180 units
A typical cross-section and installation pattern are shown
for each type of wall.
BUILDING A RETAINING WALL
Position for building a wall
on a 9° slope.
Maximum height of 1.05 m (42")
Position for building
a vertical wall.
Maximum height of 0.65 m (26")
Basic
model
Model
without blades
C1 C2
Note: It is possible to use Lafitt and Melville Tandem veneer units in the same wall.

LINEAR PATTERN WITH ONLY LAFITT OR MELVILLE TANDEM 90 UNITS
TANDEM®SYSTEM –9
BUILDING A RETAINING WALL
TYPICAL CROSS SECTION AND INSTALLATION PATTERN
90 mm LAFITT OR MELVILLE TANDEM WALL
A Straight Capping unit
90 mm
× 305 mm × 400 mm
(3 9/16" × 12" × 15 3/4")
B Structural units
90 mm
× 155 mm × variable (201, 268, 335 or 402 mm)
3 9/16" × 6 1/8" × var (7 7/8", 10 1/2", 13 3/16", 15 13/16")
C Veneer units
90 mm × 67 mm × variable (201, 268, 335 or 402 mm)
3 9/16"× 2 5/8"× var (7 7/8", 10 1/2", 13 3/16", 15 13/16")
D Perforated drain 100 mm Ø (4 in) connected
E Geotextile membrane
F Granular base 0-20 mm (0-3/4")
compacted 300 mm (12") min.
G Buried depth 150 mm (6") min.
H Clean stone 20 mm (3/4")
I Starter unit
90 mm × 200 mm × 400 mm
(3 9/16"× 7 7/8"× 15 3/4")
INSTALLATION PATTERN
A
D
I
C
B
H
E
F
0° or 9°
300 mm
(12 in) min.
G 150 mm (6 in) min.
900 mm (36 in) max
300 mm (12 in) min.

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°

TANDEM®SYSTEM –11
BUILDING A RETAINING WALL
TYPICAL CROSS-SECTION AND INSTALLATION PATTERN –
WALL WITH MIX OF LAFITT OR MELVILLE TANDEM 90 AND 180 UNITS
A Straight capping unit (connected to drains)
90 mm × 305 mm × 400 mm
(3 9/16" × 12" × 15 3/4")
B Structural units
90 mm or 180 mm × 155 mm × variable
(3 9/16" or 7 1/16" × 6 1/8" × variable)
C Veneer units
90 mm or 180 mm × 67 mm × variable
(3 9/16" or 7 1/16" × 2 5/8" × variable)
D 100-mm perforated drain (4") connected to drains
E Geotextile membrane
F 0-20 mm (0-3/4") compacted aggregate base
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
MODULAR PATTERN: 75% TANDEM 90 UNITS
25% TANDEM 180 UNITS
A
D
I
C
BH
E
F
G
0° or 9°
300 mm
(12") min.
150 mm (6") min.
900 mm (36") max
300 mm (12") min.

FFG
GF
FE
GE
GG
FE
G
E
A
B
C
D
E
F
G
H
I
12 – TANDEM®SYSTEM
BUILDING A RETAINING WALL
TYPICAL CROSS-SECTION AND INSTALLATION
PATTERN – ESPLANADE TANDEM WALL
A Esplanade chiseled capping unit
60 mm × 381 mm × 1 067 mm
(2 3/8" × 15" × 42")
B Structural units
180 mm × 155 mm × variable (335, 402, 469 mm)
7 1/16" × 6 1/8" × variable (13 3/16", 15 13/16", 18 1/2")
C Veneer units
180 mm × 60 mm × variable (350, 495, 562 mm)
7 1/16" × 2 5/8" × variable (13 3/4", 19 1/2", 22 1/8")
D 20 mm (3/4") clean stone
E Geotextile membrane
F 100 mm (4") perforated drain connected to drains
G Starter unit 90 × 200 × 400 mm (3 9/16" × 7 7/8" × 15 3/4")
H 0-20 mm (0-3/4") compacted granular base, min. 300 mm (12")
I Minimum buried depth 150 mm (6")
INSTALLATION PATTERN
LINEAR PATTERN WITH ESPLANADE
TANDEM 180 UNITS ONLY
E
E
G F
G F
562 mm
(22 1/8")
495 mm
(19 1/2")
350 mm
(13 3/4")
0° or 9°
900 mm
(36") max

C B A D F EG
LAFITT TANDEM – 90 mm UNITS LAFITT TANDEM – 180 mm UNITS
TANDEM®SYSTEM –13
BUILDING A RETAINING WALL
CURVED WALLS
Using some Tandem units yields the minimum following curves:
Curved sections of walls must generally be built
using the smallest units.
For a curved Lafitt Tandem 90 wall, use units A, B and C.
For Lafitt Tandem 180 and Esplanade Tandem walls,
units E and F must be used. Their ends are bevelled
to make it easier to install the curved wall.
Since Melville Tandem veneers all have a textured side,
the minimum bend radius is greater.
Remember that there will be a surplus of longer units for
the remainder of the wall. In building convex curves (outer curve),
the wings of structural units may have to be cut off.
STRAIGHT WALLS
To build straight Tandem walls, install the units randomly, using equal numbers of all
unit sizes according to the typical cross-section and installation pattern associated
with each type of walls.
To combine the Tandem 90 and 180 units in a single wall, just use units of each
height randomly, in a proportion that creates an aesthetically pleasing result. We
recommend the following proportions: 75% Tandem 90 and 25% Tandem 180
(in terms of wall surface).
Note that the Esplanade Tandem system requires 17% fewer structural units
than veneer units. 1 cube of 60 structural units = 4.32m2(46.52 sq. ft)
1 cube of 60 veneer units = 5.06m2(54.52 sq. ft)
When building a Tandem wall, avoid aligning vertical joints between rows as much
as possible. Allow a minimum overlap of about 67 mm (2 3/4") between modules to
make sure the vertical joints do not line up. (See Installation pattern)
90° CORNER WALL
When building a retaining wall, it is best to start with a corner to avoid breaks
and alignment of vertical joints. Specially designed veneer units are needed
to build a 90º corner. These units have a textured end.
LAFITT TANDEM
A Lafitt Tandem 90 cube contains 18 textured end veneer units per row.
To form the corner, use B, C or D veneer units.
A Lafitt Tandem 180 cube contains 8 textured end veneer units per row.
All of the veneer units (E, F and G) can be used to build the corner.
MELVILLE TANDEM
All of Melville Tandem veneers have one textured side.
ESPLANADE TANDEM
Both ends of all Esplanade Tandem veneer units are textured,
use only F & G capping to create 90° angles.
LAFITT
TANDEM 90 LAFITT TANDEM 180 MELVILLE TANDEM 90 MELVILLE TANDEM 180 ESPLANADE TANDEM 180
Convex curves (outside) 1.5 m (5 ft) 1.5 m (5 ft) 1.8 m (6 ft) 2.4 m (8 ft) 1.5 m (5 ft)
Concave curves (inside) 1.2 m (4 ft) 1.5 m (5 ft) 1.8 m (6 ft) 2.4 m (8 ft) 1.2 m (4 ft)
67 mm min.
(2 3/4")
Fill the empty space with
20 mm (3/4") clean stone
LAFITT TANDEM WALL
(PLAN VIEW)
ESPLANADE TANDEM WALL
(PLAN VIEW)
STACKING POSITION ON PALLETS (WITH A TEXTURED END)
Empty space
Cut off the extremeties
(wings) if necessary
R = 1.5 m
(5 ft)
R = 1.2 or 1.5 m
(4 or 5 ft)

14 – TANDEM®SYSTEM
BUILDING A RETAINING WALL
OUTER CORNER –
LAFITT OR MELVILLE TANDEM WALL
PRINCIPLES
An outer corner is created using veneer units with the textured
end out.
These units are reversible to form both left and right corners.
For each course, the veneer that forms the corner is affixed
to the structural unit using corner connectors designed
specifically for this purpose. It is simply of question of
alternating the placement of units from one course to the next.
We recommend adhering the elements used to make the corner
of each row using Permapro concrete adhesive.
OUTER CORNER DETAIL –
90 mm LAFITT OR MELVILLE TANDEM WALL
There are three ways of building a corner:
Option 1
Use corner veneer unit with a textured end B uncut, and begin
the wall perpendicularly leaving an empty space that will be
backfilled with clean stone
Option 2
Use corner veneer unit with a textured end C or D, uncut,
attached to structural unit A cut in half.
Option 3
Use corner veneer unit with a textured end B, C or D, cut at
222 mm (8 3/4") and begin the wall perpendicularly, pressing it
up against the existing wall. Gently hammer the freshly cut side
to obtain a similar finish as the other sides.
1ST ROW
OPTION 1
OPTION 2 OPTION 3
2ND ROW
Corner connector
Corner connector
Corner connector Corner connector
Backfilled with clean stone
Backfilled with clean stone
Veneer unit B, C or D
cut at 222 mm
Corner connector
Structural unit Veneer unit with textured end
Veneer unit C and D
with a textured end, uncut
Veneer unit B
with textured end
Structural unit A
cut in half

TANDEM®SYSTEM –15
BUILDING A RETAINING WALL
90° OUTER CORNER DETAIL
180 mm LAFITT OR MELVILLE TANDEM
There are three ways to build an outer corner using
Lafitt or Melville Tandem 180 units:
Option 1
Use an uncut textured end veneer unit E and start the wall
perpendicularly, leaving an empty space that will be backfilled
with clean stone.
Option 2
Use an uncut textured end veneer unit F or G attached to a
structural unit E, cut in half. The empty space is backfilled with
clean stone.
Option 3
Use a textured end veneer unit E, F or G cut at 222 mm, and
start the wall perpendicularly, simply pressing it up against the
existing wall. Gently hammer the freshly cut side to make the
finish similar to the other sides.
90° OUTER CORNER DETAIL
MIX OF LAFITT OR MELVILLE TANDEM 90 AND 180
To build a corner for a wall featuring a mix of Tandem 90
and 180 units, for each given row height, use corner units
of the same height (Tandem unit with associated corner veneer).
Corners are built using the options available for that height
(90 or 180), as illustrated and explained earlier in this document.
This principle applies to both outer and inner corners.
The choice of corner unit heights is a matter of aesthetics.
The 90 and 180 units must be inserted in a similar proportion
to the remainder of the wall.
OPTION 1
OPTION 2 OPTION 3
Backfilled with 20 mm clean stone
Structural unit E
cut in half
Textured end veneer unit E,
F or G cut at 222 mm
Structural unit Corner connector
Textured end veneer
unit F or G uncut
90° OUTER CORNER DETAIL
ESPLANADE TANDEM
Build an outer corner by simply overlapping the ends of the
veneer units. The corner is formed by installing a veneer F
or G unit on the end of the last Tandem unit, and inserting a
corner connector to join the two components and strengthen
the corner. Then, cut a structural unit and install it behind the
previously attached veneer.
1ST ROW 2ND ROW
Structural unit cut in half Structural unit cut in half
Veneer unit E
uncut
BUILDING A RETAINING WALL

16 – TANDEM®SYSTEM
OPTION FOR ESPLANADE TANDEM
For the Esplanade Tandem wall, we recommend using units F
and G for the inner corners. Use half a structural unit to fill
the space created in installing the inner corner. It will support
the cap and will be attached to the adjacent structural unit
using a double-sided connector. (See the following illustration.)
BUILDING A RETAINING WALL
INNER CORNER
Build a Lafitt, Melville or Esplanade Tandem inner corner
according to the principle shown here, using Tandem 90
units C or D and 180 units E, F or G.
45° CORNER
It is also possible to build corners on a 45° angle. Simply cut
each Tandem unit used to make the corner on a 22.5° angle.
These Tandem units must be adhered together using Permapro
concrete adhesive on the horizontal and vertical sides.
INNER CORNER, PRINCIPLES
TANDEM CUT AT AN ANGLE
22.5°
1ST ROW 2ND ROW
Tandem 90 units C or D
and 180 units E, F or G
Double-sided
connector
Cut the structural
unit in equal halves
Double-sided
connector
Second half of the
structural unit

TANDEM®SYSTEM –17
45°
BUILDING A RETAINING WALL
RETAINING WALL CAPPING
The Lafitt Tandem retaining wall is completed using Lafitt Tandem capping
units (90 × 305 × 400 mm). The Melville Tandem wall is finished with the use
of the Melville Tandem Capping units (60 mm × 305 mm × 600 mm). To cap a
wall with a 90° corner, capping units must be cut at a 45° angle.
Lafitt or Melville Tandem capping units are also used to cap curved walls.
The units must be bevelled on site to match the final shape of the wall.
Options: Straight and bevelled capping units from the Celtik wall system and
the Esplanade chiseled capping units can also be used to highlight the wall’s
finish (different colours and textures).
Esplanade Tandem retaining walls are capped by placing the Esplanade
chiseled capping units (60 × 381 × 1067 mm or 2 3/8" × 15" × 42"). To cap a
90° corner, simply install two capping units at a 90° angle. Note that one out
of two Esplanade chiseled capping units is textured on 3 sides (2 sides and
one end). For curved walls, capping units must be bevelled on site to match the
final shape of the wall.
Options: Straight and bevelled Celtik wall system capping units
and Lafitt or Melville Tandem capping units can also be used.
Note that all capping units must be glued to the last row of Tandem units using
Permapro concrete adhesive.
If necessary, level the second last course with stone screening. Make sure
the surface is clean, so that the capping can be glued to the top course with
Permapro concrete adhesive.
Glue the capping units
to the last row.
Level with stone
screening
if required.
ESPLANADE RETAINING WALL CAPPING
For a better finish, grind
the ends if needed.

18 – TANDEM®SYSTEM
BUILDING A DOUBLE-SIDED WALL
DOUBLE-SIDED TANDEM UNIT ASSEMBLY
Installing a double-sided wall requires the use of two veneer units held together
using connectors. Connectors are inserted into the mortises on the veneer units
thus connecting them two by two in order to create the double-sided Tandem unit.
The work is complete once 20 mm (3/4 in) clean stone is placed between the
veneers of every other course, and the capping unit is installed. Lafitt and Melville
Tandem 90 and 180 veneer units, as well as Esplanade units can be used to build
straight or curved double-sided walls, as well as 90° corners.
Allowable heights
The Tandem wall system can be used to build a double-sided wall
with a maximum above-ground height of 711 mm (28 in). The wall is built
completely vertical without a slope.
DOUBLE-SIDED LAFITT
TANDEM MODULES
DOUBLE-SIDED ESPLANADE TANDEM MODULE
DOUBLE-SIDED TANDEM UNIT ASSEMBLY
268 mm (10 9/16 in)
90 mm (3 9/16 in)
Veneer unit
Veneer unit
Double-sided connector
286 mm (11 1/4")
180 mm
(7 1/16")
Veneer unit
Double-sided connector
Note: Lafitt and Melville Tandem 180 wall modules must be assembled using pairs of double-sided
connectors installed one on top of the other for greater stability.
268 mm (10 9/16 in)
STARTER UNITS
To build the double sided Tandem wall, begin by placing the
starter unit directly on the granular base perpendicular to the
wall and levelling it.
STARTER UNIT
INSTALLATION
(PLAN VIEW)
STARTER UNIT
(PLAN VIEW)
200 mm
400 mm

TANDEM®SYSTEM –19
A
C
D
B
F
E
G
There are four ways to build a double-sided wall:
Using only Lafitt or Melville Tandem 90 units
Using only Lafitt or Melville Tandem 180 units
Using a mix of Lafitt or Melville Tandem 90 and 180 units
in the same wall
Using only Esplanade Tandem units
To build a solid structure, the empty space inside the double-
sided Tandem unit must be filled with 20 mm (3/4") clean stone
on every second row. Before installing the capping, tap lightly
on each side of the wall with a rubber hammer to help compact
the aggregate between the veneer units.
Double-sided Tandem units are randomly installed on starter
units, using an equal number of all units. The same installation
patterns as for retaining walls are used here (see the installation
patterns in the “Retaining Wall” section). Each veneer unit
of the first row must be glued to the starter units with the
Permapro concrete adhesive.
BUILDING A DOUBLE-SIDED WALL
150 mm (6") min.
711 mm (28 in) max
DOUBLE-SIDED LAFITT or MELVILLE TANDEM
WALL WITH 90 mm VENEER UNITS
Note: Quantity of connectors required:
Lafitt and Melville Tandem 90 wall
7 connectors per sq. ft of double-sided wall (74 connectors
per m2) based on one of the sides of the wall
Lafitt and Melville Tandem 180 wall
5.5 connectors per sq. ft of double-sided wall (57 connectors
per m2) based on one of the sides of the wall
Esplanade Tandem wall
2.5 connectors per sq. ft of double-sided wall (24 connectors
per m2) based on one of the sides of the wall
For a double-sided Lafitt, Melville and Esplanade Tandem wall, we
recommend gluing all of the rows together.
STRAIGHT DOUBLE-SIDED WALL
When building a straight wall, assemble veneer units of the same
size using the double-sided connector. Because the veneer units
come in different lengths, several layouts are possible.
TYPICAL CROSS SECTION
A Capping unit (for double-sided wall)
B Veneer units
90 mm × 67 mm × variable
(3 9/16" × 2 5/8" × var)
C Double-sided connector
D 20 mm (3/4") clean stone
E Granular base 0-20 mm (0-3/4")
compacted 300 mm (12") min.
F Minimum buried depth 150 mm (6")
G Starter unit
90 mm × 200 mm × 400 mm
(3 9/16" × 7 7/8" × 15 3/4")
UNITS A –A
90 mm × 67 mm × 201 mm
(3 9/16" × 2 5/8" × 7 7/8")
UNITS B –B
90 mm × 67 mm × 268 mm
(3 9/16" × 2 5/8" × 10 1/2")
UNITS C –C
90 mm × 67 mm × 335 mm
(3 9/16" × 2 5/8" × 13 3/16")
UNITS D –D
90 mm × 67 mm × 402 mm
(3 9/16" × 2 5/8" × 15 13/16")

20 – TANDEM®SYSTEM
A
DF
G
E
C
B
A
DF
G
E
C
B
TYPICAL CROSS SECTION
A Capping unit (for double-sided wall)
B Veneer units
180 mm × 67 mm × variable
(7 1/16" × 2 5/8" × variable)
C Double-sided connector
D 20 mm (3/4") clean stone
E
Granular base 0-20 mm (0-3/4")
compacted 300 mm (12") min.
F Min. buried depth of 150 mm (6")
G Starter unit
90 mm × 200 mm × 400 mm
(3 9/16" × 7 7/8" × 15 3/4")
TYPICAL CROSS SECTION
A Capping unit (for double-sided wall)
B Veneer units
90 mm ou 180 mm × 67 mm × variable
(3 9/16" ou 7 1/16" × 2 5/8" × variable)
C Double-sided connector
D 20 mm (3/4") clean stone
E
Granular base 0-20 mm (0-3/4")
compacted 300 mm (12") min.
F Min. buried depth of 150 mm (6")
G Starter unit
90 mm × 200 mm × 400 mm
(3 9/16" × 7 7/8" × 15 3/4")
BUILDING A DOUBLE-SIDED WALL
DOUBLE-SIDED LAFITT AND MELVILLE TANDEM WALL
WITH 180 mm VENEER UNITS
Note: Lafitt and Melville Tandem 180 wall modules must be
assembled using pairs of double-sided connectors installed one
on top of the other for greater stability.
DOUBLE-SIDED LAFITT AND MELVILLE TANDEM WALL
WITH 90 AND 180 VENEER UNITS
UNITS E –E
180 mm × 67 mm × 335 mm
(7 1/16" × 2 5/8" × 13 3/16")
UNITS F –F
180 mm × 67 mm × 402 mm
(7 1/16" × 2 5/8" × 15 3/16")
UNITS G –G
180 mm × 67 mm × 469 mm
(7 1/16" × 2 5/8" × 18 1/2")
180 mm (7 in)
300 mm (12 in) min.
180 mm (7 in)
720 mm (28 in) max
300 mm (12 in) min.
711 mm (28 in) max