Manufacture

The production and consumption of Portland Cement has an impact on the environment. However, published data (BRE The Green Guide to Specification) clearly shows that precast concrete has the least environmental impact of all hard landscape materials.

Marshalls has commissioned the leading independent authority in this area to calculate the CO₂ embodiment of its range of products. This working brief has now been extended to investigate the wider impact rather than just the CO₂ impact. The results of this work are due late spring ’07, watch this space!

However, what the current figures already demonstrate is that wet cast paving generates just 49.4% of the equivalent kgs of CO₂ compared with imported natural stone from India.

Also, our continued research and development has led to the innovative uses of replacement materials, enabling Marshalls to achieve such low CO₂ emissions for all its concrete paving. Indeed our ‘new’ concrete block paving mix designs reduce CO₂ embodiment by up to 38%. This has been achieved by the use of materials such as:

• Ground Granulated Blast-furnace Slag – a recycled material generated from
  iron manufacture, processed into cementitious powder
• Pulverised Fuel Ash – a by-product of the combustion of coal in power stations
• Aggregates – recycled aggregates (from our own quarries, and bought
  in) used to replace virgin aggregates
• Crushed Concrete – waste material from our own production is crushed on site and recycled into new production