20.20A Grey Block (Biscuitless Knockout Deep Channel) by National Masonry are a professionals choice for an all round retaining wall system. Concrete Grey Blocks are manufactured utilising recycled fly ash to provide a lightweight, high strength product. Concrete Grey Blocks are commonly used for construction on houses, schools, and various commercial and domestic projects.

Choosing the right Concrete Grey Block 

Before selecting, you should ensure this product meets your projects requirements. Certain Concrete Grey Blocks are lightweight, heavy duty and/or fire rated. Please check the Additional Information. Please consult our friendly sales team if you are unsure on the best Concrete Grey Block for your construction needs.

20.20A Grey Blocks Specifications

• Type: Deep Channel Biscuitless Knockout
• Size: 390 x 190 x 190mm - 12.6kg
• Units per pallet: 108
• Material: Concrete
• Standards: All National Masonry and Stoneworks Pavers adhere to the Australian Standards for Salt Resistance (AS/NZS 4456.10:2003)

The 20.20A Grey Block is simple to install and will easily stack together to form straight or curved walls, their unique universal corner block enables 90 degree corners without any fuss. Using aggregates and iron oxides these garden wall blocks will retain their colour and structure, even under the Australian sun. 

20.20A Grey Blocks Applications

• Commercial Buildings
• Homes
• Schools 
• Retaining Walls 

Council Requirements

When planning to build a retaining wall it is always recommended to contact your local council for any information or planning approvals.

• Brisbane City Council Building a retaining wall
• Ipswich City Council Building and planning
• Gold Coast Council – Retaining walls
• Toowoomba – Building approvals and heights for retaining walls
• Moreton Bay Regional Council – Building approval
• Logan City Council – Building Approvals Fact Sheet
• Redlands City Council – Minor building projects
• Sunshine Coast Council – Property fences and retaining walls