Leiths (Scotland) Ltd

  Providing a Complete Service for Construction and Civil Engineering Projects

·      Tests are performed and products are supplied in compliance with British Standards.

·      The labs operate to a strict control system within a BS EN ISO/IEC 17025:2000 management system.

·       Sampling and testing can also be provided for external clients.

·       Innovative and proprietary materials and application are under continuous development

Porous Asphalt pavement is a paved surface and sub-base used for the construction of 'Sustainable Urban Drainage Systems'. Conventional surface water drainage techniques can cause flooding and pollution to the detriment of water resources and the natural environment. A more sustainable solution is to use methods inspired by natural processes. These new methods use permeable surfaces that permit surface water to enter the underlying construction.

Porous asphalt allows the ingress of water to the lower layers where water is stored and conveyed through the sub-base construction. Permeable surfaces remove the need for traditional drainage ancillaries and can be used as attenuation or infiltration devices.

The two grades of material currently produced are specified in BS 4987-1:2003, see clause 8.1 and clause 8.2. Either a 100/150 pen bitumen with fibres or a polymer modified bitumen is used. Laboratory and plant trials have been carried out which indicate that the pore space of these materials is approximately 16%.