TRANSFORMING PAVING
WITH CONCRETE BLOCK PERMEABLE OVERLAYS
Low-intervention permeable paving overlays can transform worn-out paving and deliver SuDS , green infrastructure and healthy streets . To understand how , it ’ s worth reminding ourselves of the unique characteristics and attributes of modular concrete paving generally – as the trade body Interpave explains .
Concrete Block Paving technology is based on high-strength , interlocking units installed with granular material filled joints and laying course . It enables small displacements between blocks , while retaining interlock , to create a particularly durable wearing course over structural layers below and forming a ‘ flexible pavement ’. Decades of use internationally have demonstrated its suitability for the most taxing paving applications . A wide choice of shapes , styles , colours and finishes – including natural aggregates – add a richness , diversity , visual interest and a human scale to the urban realm .
Concrete Block Paving is slip resistant , durable , strong and sustainable . Modular concrete paving delivers fast , low-cost installation using weatherindependent , ‘ dry ’ construction methods . There are no curing , hotwork or noxious fume problems and only small plant and equipment is needed , with noise and disturbance minimised . With an extremely long lifespan , blocks can be taken up and re-used without processing for repairs , changing demands and layouts , or new schemes – saving carbon and meeting ‘ circular ’ economy ’ criteria .
Increasingly Popular Permeable Paving Concrete Block Permeable Paving ( CBPP ) enhances this technology as a well-established , multi-functional sustainable drainage ( SuDS ) technique . It simply combines selfdrained , safe and attractive surfaces for a wide range of applications with attenuation , storage , pollution treatment and conveyance of rainwater runoff . The difference with CBPP is angular aggregate ( 2 / 6.3mm ) – not sand – used to fill enlarged joints and as a laying course . Then , pavement layers of voided material ( typically 4 / 20mm ) below accommodate water , whilst still providing the required structural performance . CBPP can also accept additional runoff from adjacent impermeable paving and roofs up to twice its own area .
By its very nature , CBPP requires no additional land-take for water storage or management , and no gulleys with related pipework . Its unique capabilities include source control and delivering a gradual flow of clean water , for example to open SuDS features , for amenity or biodiversity , to drainage systems or into the ground . More than 25-years usage has proven it to be a robust , resilient and adaptable technology , used on projects ranging from footpaths to container terminals , with the reassurance of proven engineering design solutions .
Both construction and whole-oflife costs of CBPP have been shown to be lower than for conventional
paving and drainage , and it requires only limited , straightforward maintenance without clogging problems . It ’ s important to remember that CBPP is unlike – and not to be confused with – permeable materials , which behave very differently .
Innovative Paving Overlays Concrete Block Permeable Paving Overlay is a deceptively simple , innovative approach to retrofitted CBPP , delivering SuDS as part of low-intervention repair , maintenance or regeneration . The
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