How to Install Novum Wall for a Durable Retaining Wall
A retaining wall rarely fails because the concrete itself is weak. More often, the problem starts below or behind the wall: an uneven base, trapped water, poorly compacted fill, or a wall built without following the engineered layout. Knowing how to install Novum Wall correctly means treating the wall, the soil, and the drainage path as one system from the first excavation pass.
Novum Wall provides the speed and durability advantages of precast concrete, but those advantages depend on careful site preparation and placement. A properly installed wall can improve usable space, control grade changes, protect pavement or landscaping, and hold up through Midwest freeze-thaw cycles. A rushed installation can create settlement, shifting, drainage problems, and avoidable repair costs.
Start With the Approved Wall Plan
Before excavating, confirm what the wall is designed to do. A short landscape wall and a wall holding back a parking area, driveway, slope, or building-adjacent grade do not have the same requirements. Wall height, soil conditions, surcharge loads, slope above or below the wall, utilities, and water flow all affect the installation approach.
Use the approved product details and engineered plans for the project. If the wall requires reinforcement, geogrid, a specific leveling pad, connection components, or a particular drainage section, those details are not optional substitutions. They are part of the wall’s structural design.
This is also the time to verify permits, property lines, and utility locations. Call for utility locating before digging, and make sure the finished wall will not direct runoff toward a neighboring property, sidewalk, foundation, or roadway. On commercial and municipal work, coordinate elevations with grading, paving, and drainage plans before materials arrive.
Prepare the Site Before Delivery
Novum Wall units are precast concrete components, so installation typically requires appropriate handling equipment and a clear work area. Plan delivery and staging so the machine can reach the wall line without driving over the prepared base or finished drainage zone.
At minimum, the crew should have a capable excavator or loader, approved lifting equipment, a laser or transit level, compaction equipment, and the aggregate specified for the base and drainage zone. The equipment must be sized for the actual unit weights and lift reach. Never improvise lifting points or use damaged rigging.
Establish the wall alignment and finished elevations with stakes, string lines, and control points. It is far easier to correct an alignment issue before excavation than after several courses are set. Identify low points and planned outlets early so water has a defined route away from the wall.
Excavate for a Stable, Draining Foundation
Excavate along the wall line to the required depth and width shown on the plans. Remove loose topsoil, roots, organic material, soft pockets, construction debris, and any unsuitable native soil. These materials can compress over time, allowing individual units or longer sections of wall to settle unevenly.
The excavation should provide room for the leveling pad, the base of the wall, the drainage aggregate behind it, and any required reinforcement. Avoid cutting the trench too narrowly. Crews need space to place and compact aggregate correctly, not simply push loose stone into gaps after the wall is in place.
If the excavation reaches wet, pumping, or unstable soil, stop and address it before proceeding. Depending on the site and engineering direction, the solution may involve overexcavation, replacement with suitable compacted aggregate, geotextile separation, or revised drainage. Covering a soft area with a thin layer of stone does not create a stable foundation.
In Nebraska and the surrounding region, frost and wet spring conditions make base preparation especially important. Water-saturated soil can lose bearing capacity quickly. A base that looks acceptable on a dry afternoon may behave very differently after rain or thaw if drainage was overlooked.
Build and Level the Base Carefully
Place the specified leveling material in controlled lifts and compact it to the project requirements. Crushed aggregate is commonly used because it can be graded accurately and drains well, but use the material called for in the wall design. The goal is a firm, uniform, level bearing surface, not a thick layer of loose rock that can move under load.
Check the base elevation frequently with a laser level or transit. The first course establishes the position of every unit above it, so a small error at the base can become a visible alignment or elevation problem as the wall rises. Take the time to correct high and low spots before setting concrete.
Do not use the wall units to force the base into shape. Repeatedly lifting, lowering, or rocking a unit to compensate for poor grade can disturb the aggregate and leave voids below the bearing surface. Set each unit only after the base is prepared to the correct line and elevation.
How to Install Novum Wall Units Accurately
Set the first units at the planned starting point using approved lifting methods. Check each unit for line, level, and proper contact with the prepared base. The first course should be straight, consistently elevated, and aligned with the intended wall face. Confirm these items as work progresses rather than waiting until the end of the run.
Keep joints, connections, and any alignment features clean. Aggregate, soil, ice, or concrete chips caught between units can prevent proper seating. If a unit does not sit correctly, lift it, clean the bearing area, correct the base, and reset it. Forcing a poor fit usually creates a larger correction later.
Continue setting units according to the product details and wall plan. Where the layout includes corners, curves, steps, caps, or changes in elevation, verify the sequence before committing to the next section. Precast wall systems install faster than site-built concrete when the crew follows the layout, but speed should not replace checks for face alignment, batter, and elevation.
On taller walls or walls with structural loading, the installation may include geogrid or other reinforcement at designated courses. Install it at the required length, elevation, and direction, then place and compact backfill according to the engineering details. Do not shorten reinforcement because of a field obstacle without approval. Adjusting the layout may be necessary, but the engineered wall performance must remain intact.
Drainage Is Part of the Wall, Not an Add-On
Water pressure behind a retaining wall can be more damaging than the soil being retained. A drainage zone of clean aggregate behind the units gives water a place to move instead of allowing it to build pressure against the wall face. Use the drainage material and width specified for the project.
Install drain pipe where shown on the plans, maintain positive fall to a suitable outlet, and protect outlets from blockage or erosion. A pipe with no outlet is not a drainage solution. Likewise, do not bury the top of the wall area under impermeable soil or hardscape without accounting for where surface water will go.
Separate drainage aggregate from fine native soil when the design calls for filter fabric or another separation method. Without separation, fines can migrate into the stone over time and reduce its ability to drain. This is a practical detail with long-term value, particularly on clay-heavy or wet sites.
Backfill in Controlled Lifts
Backfill behind the wall as the installation advances, not after the entire wall is erected. Place approved fill in manageable lifts and compact each lift with equipment appropriate for the location. Keep heavy compaction equipment far enough from the wall face to avoid pushing units out of alignment, especially during the early stages of construction.
Use the correct backfill material. Clean aggregate belongs in the drainage zone, while reinforced soil zones and general backfill areas should match the approved plan. Do not place organic soil, frozen soil, saturated fill, or large debris behind the wall. Those materials can settle or trap water.
After each lift, recheck wall line and elevation. Small adjustments are manageable while work is active. Once the area is fully backfilled, paved, landscaped, or loaded with traffic, correcting movement becomes more disruptive and expensive.
Finish the Grade to Protect the Investment
The final grade should direct surface water away from the wall and keep the drainage path open. Complete caps, landscaping, hardscape edges, and erosion-control features in a way that does not interfere with the wall’s drainage or add unplanned loads near the top of the wall.
Before demobilizing, inspect the completed installation for consistent alignment, secure seating, proper drainage outlets, clean joints, and finished grades. Documenting the installation and retaining the approved plans also helps property owners and maintenance teams understand what is behind the wall before future improvements are made.
For projects with challenging soil, major elevation changes, traffic loading, or a tight schedule, practical installation support can prevent costly field decisions. Precast Solutions can help connect customers with retaining wall contractors who understand regional conditions and the value of building the base, drainage, and wall system right the first time.