Size the trench so there's enough room for the retaining wall block and at least 8 in. of space behind it. Excavate deep enough to completely bury at least one full course, including space for 6 to 8 ...

MINNEAPOLIS, MN--(Marketwire - Oct 17, 2012) - Allan Block Corporation, a leading provider of retaining walls, is proud to announce that the Allan Block retaining wall system is now approved by the BC ...