Topmix Permeable

Topmix permeable is a concrete which offers improved permeability properties over traditional solutions. Combining both the trafficking surface and the drainage solution simplifies the construction process and reduces costs.

A typical system consists of a layer of Topmix Permeable installed on top of an aggregate sub-base, which is in turn laid onto undisturbed soil or a capping layer. The structure and dimensions of each layer will depend on the application and the design of the system.

Unlike conventional concrete, it has a high void content of between 20–35%. This allows surface water to drain through into the sub-strata and dissipate naturally, reducing the risk of surface water flooding and watercourse contamination.

Features and benefits:

• Offers comparable skid resistance to low texture asphalt and concrete when tested in accordance with ENG1-961 and HD25/011 (low speed, typically 30 mph applications).

• Not suitable where there will be very heavy silt loads (e.g. stockpiling sawdust or large recycling centres). Also not suitable for HGV delivery routes (supermarkets etc.), car park ticket barriers, bus routes and industrial yards.

• Conforms to BREEAM and LEED standards.

• Supports water capture systems for grey water recycling.

• Filtration reduces water pollution and reduces the cost of treatment.

• Contributes to the natural recharge of groundwater.

• Reduces heat build-up and retention, reducing the UHI effect.

Applications:

Three typical best practise applications are available as follows; full infiltration, partial infiltration and full attenuation. These three designs can be used for a wide range of practical applications, including:

• Low volume residential roads and parking bays.

• Pavements, bike and pedestrian pathways.

• Patios.

• Tennis courts and hardstanding for sports facilities.

• Road shoulders.

• Swimming pool decks.

• Alleyways and driveways.

• Greenhouse floors.

• Pavement edge drains and gutters.

• Underneath permeable blocks for ground stabilization.