Estimated reading time: 4 minutes

Key Takeaways

• Market Square Shopping Centre in Plettenberg Bay gained extra parking by excavating behind the centre and moving the embankment closer to the boundary.
• LFC Construction built the wall with 12,392 Terraforce L11 blocks and 2,040 m³ of engineered fill.
• Reinforced foundations and geogrid tiebacks let the wall carry the parking above, and installation took 57 days.

A busy shopping centre cannot stop trading while it adds parking. At Market Square Shopping Centre in Plettenberg Bay, more bays were needed, the only available space sat on a slope below the N2, and the programme left very little room for delay. LFC Construction, a Terraforce Recommended Contractor, delivered the engineered Terraforce retaining walls that made the new parking possible.

By the end of this article, you will know:

• what a geogrid retaining wall is and why it suits parking areas
• how the wall was founded and reinforced for daily vehicle loads
• how the installation was completed in 57 days

What Is a Geogrid Retaining Wall?

A geogrid retaining wall is a block-faced wall in which layers of high-strength polymer grid are laid into compacted backfill and connected to the wall face. The grid locks the soil into a single reinforced mass, allowing the wall to retain greater heights and carry loads such as parking or buildings above it.

This approach is also known as Mechanically Stabilised Earth (MSE), one of LFC’s core specialist services. The block face gives the finished look, while the reinforced soil behind it does most of the structural work. That makes a geogrid retaining wall well suited to commercial sites, where the ground above will carry vehicles every day.

Creating Extra Parking Below the N2

Market Square needed more parking for its growing customer base. The chosen area lay behind the centre on the western side, below the N2. The plan was to excavate the existing slope and move the embankment closer to the boundary line, gaining as much level, usable space as possible (Terraforce).

Fred Laker of iCOS Engineers designed the structure. Terraforce L11 blocks were selected as the most cost-effective option for a wall that had to reach a significant height while supporting a parking area on top. The L11’s load-bearing capacity was central to that choice.

Reinforcement Built for Daily Vehicle Loads

Parking areas place constant, shifting loads on the ground below. Every layer of this wall was engineered with that in mind:

• Foundation: a reinforced concrete foundation sized for the height of the wall.
• Lower wall section: additional reinforced concrete in the lower courses, where loads are greatest.
• Geogrid tiebacks: XGrid PET-C-0 55/20 tiebacks laid throughout the backfill zone to reinforce the retained soil.
• Engineered fill: 2,040 m³ of engineered fill placed and compacted behind the wall.

Soil and block act together as one structure. For the centre, that means a level car park, an upright wall and no rework once the bays are in use, the outcomes reinforced retaining walls should deliver on any commercial site.

Completing the Installation in 57 Days

From the start, the programme was tight. The installation team placed 12,392 Terraforce L11 blocks and all 2,040 m³ of fill in 57 days, in mid-2025 (Terraforce). Fast completion let the centre bring the extra parking into use quickly and kept disruption to trading to a minimum.

That pace relies on close coordination across the project team and consistent materials: every block came from a Terraforce licensed manufacturer in the South Cape.

LFC’s Garden Route office sits close to projects like this one. As soil retention specialists, LFC handles work through Design. Supply. Install., and every team runs under experienced, full-time supervision. Speed never comes at the cost of building to the engineer’s drawings.

Frequently Asked Questions

How long does it take to build a geogrid retaining wall?

It depends on wall height, length, soil conditions, site access and how the programme is phased. At Market Square, 12,392 blocks and 2,040 m³ of engineered fill were installed in 57 days, showing what is possible with good planning and a dedicated, supervised team.

Does every retaining wall need geogrid?

No. Low walls under light loads can often stand without it. Geogrid is needed where the height or the load above, such as parking or a building, is more than the blocks can retain alone. The engineer’s design decides where it goes and at what spacing.

Can a shopping centre keep trading during retaining wall works?

In many cases, yes. At Market Square, the wall was built behind the centre, and quick completion limited disruption to ongoing operations. Careful planning of access, deliveries and work areas is what keeps a site open.

Add Parking Capacity to a Constrained Site

Limited space and a tight programme do not have to block a parking expansion. Market Square shows how a well-engineered geogrid retaining wall can create usable ground on a slope, carry daily vehicle loads and be delivered on schedule.

If your site needs more level space, contact LFC Construction for a site assessment, quote or tender enquiry. Explore LFC’s retaining wall services or speak to the team directly:

• Garden Route office: Adri De Klerk, 074 272 7699, adri@lfcon.co.za
• Western Cape head office: Charl Johnsen, 079 073 7894, charl@lfcon.co.za