Installation Guide

INSTALLATION INSTRUCTIONS
Prepare the Base Leveling Pad.
Excavate the base trench to the designed
width and depth. Start the leveling pad at the
lowest elevation along the wall alignment. Step
up in 8" (200mm) increments with the base as
required at elevation change in the foundation.
Level the prepared base with maximum 6"
(150mm) lifts of well-compacted granular fill
(gravel, road base, or ½" to ¾" [10 - 20mm]
crushed stone). Compact to 95% Standard
Proctor or greater. Do not use PEA GRAVEL or
SAND for leveling pad.
Install Fill & Compaction.
Provide ½" - ¾" (10 - 20mm) clean
crushed stone drainage fill behind
the units to a minimum distance
behind the tail of 6" (150mm). Fill all
open spaces between units and open
cavities/cores with the same drainage
material. Proceed to place backfill
in maximum 6 - 8" (150 - 200mm)
layers and compact to 95% Standard
Proctor with the appropriate
compaction equipment.
Install the Base Course.
Place the first course of Keystone units end
to end (with face of wall corners touching)
on the prepared base. The receiving pin
holes should face upward, as shown. Make
sure each unit is level. Leveling the first
course is critical for accurate and acceptable
results. Keystone recommends minimum
embedment depth for below grade
placement of Keystone units on a ratio of 1"
(25mm) below grade for each 8" (200mm)
of wall height above grade or one unit,
whichever is greater.
Install Additional Courses.
Place the next course of Keystone
units over the fiberglass pins, fitting
the pins into the triangular shaped
receiving hole in the units above.
Push the units toward the face of the
wall until they make full contact with
the pins. Continue backfilling and
building to desired top elevation.
Insert the Fiberglass Pins.
Place the straight fiberglass pins into the
holes of each Keystone unit as required.
Once placed, the pins create an automatic
setback for the additional courses. Place
fiberglass connecting pins in the front holes
for near vertical (
1
⁄8" or [3mm]) setback and
in the rear pin holes for 1
1
⁄8" (29mm) setback
per course.
Capping the Wall.
Complete your wall with the
appropriate Keystone capping
units. With units dry and clean,
use exterior construction grade
adhesive on the top surface of the
last course before applying cap units.
Backfill and compact to finish grade.
STEP 1
STEP 2
STEP 3
STEP 4
STEP 5
STEP 6
III
STRUCTURAL WALL | KEYSTONE STANDARD
®
III STRAIGHT SPLIT
©2017 Keystone Retaining Wall Systems LLC
Keystone Retaining Wall Systems LLC • A Contech Company
4444 West 78th Street • Minneapolis, MN 55435
[phone] • www.keystonewalls.com
Note: If drain tile is required for your project, consult an engineer or visit www.keystonewalls.com/resources for more information.