Cover frame adjusting units are reinforced 65mm deep units which can be used in place of engineering bricks to adjust the ductile or cast iron covers and frames to the required level.

Adjusting units are available for the following access sizes. 

600 x 600, 675 x 675, 750x600, 1200x675
600 x 600  -  eccentric opening to be used in conjunction with a 750 x 600 cover slab opening.

The advantages of adjusting units are:

• They can be quickly and easily installed by semi-skilled labour
• There are fewer joints which reduce the likelihood of infiltration
• All concrete manhole units can be ordered from one source
• There is a reduced risk of on site damage and pilferage

Two Piece Units

Two piece adjusting units are now available with a 600x600 and a 675x675 opening.

2 piece adjusting units offer the following advantages

Each section weighs less than 25kg enabling one man to handle the units and comply with manual handling regulations.

No requirement for bricklayers due to ease of installation.

Quicker to install than brickwork.

Scottish Water seating slab

Special seating slabs 1125 x 1125 x150mm thick, to comply with Scottish Water Services Specification are available with access sizes 600x600, 675 x 675, 750 x 600 and 750 x 750.