Walls over 4 feet tall generally require structural engineering and a city permit in most Minnesota municipalities. Shorter walls under 4 feet are typically cosmetic and don’t need engineering, but they still benefit from drainage tile and proper base prep to avoid failure. We handle engineering coordination and permit pulls as part of every project that needs them.

With proper base prep, drainage and geogrid reinforcement, a segmental block or boulder wall should hold for 25+ years without measurable movement. Natural stone performs similarly. The failure point is almost never the blocks themselves — it’s water building up behind the wall, and our drainage tile and filter fabric are built to eliminate that.

Every wall we build gets a 4-inch perforated drain tile at the base, wrapped in filter fabric to keep silt from clogging it, and backfilled with clean crushed aggregate. Water that collects behind the wall flows out through the drain tile instead of building the hydrostatic pressure that pushes walls over. This is where most DIY and cut-rate installs fail.

Walls 4 feet and taller typically need a city permit and structural sign-off — we pull the permit and manage inspections so it’s not on your plate. We also check property-line setbacks, septic clearances and drainage easements on the site survey, before any design work starts.

Block (Belgard/Unilock) gives the most uniform look and the easiest future repairs. Natural stone has more organic character but typically costs 40-60% more. Boulder walls suit large, naturalistic lots. We bring samples to the site visit so you’re deciding in person, not off a brochure.