Block and masonry retaining walls.

Two different things called 'block walls'

Segmental block systems stack without mortar and rely on geometry, mass and sometimes geogrid reinforcement into the fill behind. Core-filled masonry walls are built on a reinforced concrete footing with steel through the cores.

They're built very differently and suit different heights and loads. We'll explain which one your site actually calls for.

Where block walls suit

• Front yard and street-facing walls
• Garden terracing where finish matters
• Planter and courtyard retaining
• Curved wall lines
• Matching existing brick or masonry
• Sites where the wall is highly visible

Footings are the whole job

A masonry retaining wall is only as good as the footing under it and the steel through it. Cracked block walls are usually telling you about footing movement or load the wall was never designed for — not about the blocks.

Drainage behind block

Block walls need the same treatment as any other retaining wall: a drainage layer, a collection line where appropriate and an outlet. Water staining and efflorescence on the face is generally water getting through the wall instead of being taken away behind it.

Engineering

Reinforced masonry retaining walls of any real height commonly need engineering design. We'll flag that at quote stage so it's part of the plan.