Full base, stone finish

The base should consist of a free draining crushed stone. Although often used, MOT Type 1 is not suitable as it is, in most cases, not free draining. MOT Type 1x (now DfT Clause 805 Type 3) is, though, appropriate. Depth of stone will depend on the drainage characteristics of the existing ground. Assuming reasonably free draining ground then the base for a car park would typically be 150-200 mm of stone, well compacted and overlaid with a 30mm blinding layer of sharp sand.

Gridforce pavers are laid onto the sharp sand prior to filling with free draining angular stone of maximum particle size 14mm (10mm gravel is ideal). Some clients prefer to cover the pavers under a layer of stone, but for a neater and more manageable finish, full enclosure of all stone within the cells is recommended.

Free design advice is available and site/client visits can be arranged. Gridforce is available as supply only or as supply and lay.

Specification Clauses

(a)  GF paver system

The permeable ground reinforcement system shall be GF30/GF40/GF50* (or similar approved) from Gridforce Ltd, manufactured from recycled low density polyethylene, u.v. stabilised and coloured black or green**. Each paver measures 500 x 500mm and is delivered to site in pre-connected panels of 4no. pavers.  Panels to be connected by interlocking lugs and slots, white or yellow inserts are available for demarcation of standard or disabled parking bays, and creation of direction arrows.  Gridforce ‘J’ pins are to be used to secure pavers cut on site and on installations where pavers are to be laid on a severe gradient.

The base (subject to ground conditions) is to be a 150-200mm deep layer of Type 3 or similar free draining crushed stone (not M.O.T. Type 1), well compacted and overlaid by 30mm of sharp sand.  Pavers should then be vibrated, ensuring that c.10mm of the sand is worked up into the paver cells.  Paver cells should then be loose filled with angular free draining stone, maximum size 14mm.

* Delete as necessary

** Standard colour is black but GF40 is ex stock in green also and other colours are available to order, subject to quantity.

(b)  ‘Park’ paver system

The permeable ground reinforcement system shall be Park30/Park40* (or similar approved) from Gridforce Ltd, manufactured from recycled low density polyethylene, u.v. stabilised and coloured green.  Each paver measures 580 x 390mm and is delivered to site in pre-connected panels of 4no. pavers.  Gridforce ‘J’ pins are to be used to secure pavers cut on site and on installations where pavers are to be laid on a severe gradient.

The base (subject to ground conditions) is to be a 150 - 200mm deep layer of Type 3 or similar free draining crushed stone (not M.O.T. Type 1), well compacted and overlaid by 30mm of sharp sand.  Pavers should then be vibrated, ensuring that c.10mm of the sand is worked up into the paver cells.  Paver cells should then be loose filled with angular free draining stone, maximum size 14mm.