Harmer Uni-Ring Supports



Harmer Uni-Ring is a versatile, economical system for concealed drainage beneath paving slabs, based on shallow injection moulded polyethylene rings.

Applications, Materials & Installation

  • Harmer Uni-Ring is ideal for use on terraces, walkways and balconies and is especially suited for inverted roof constructions where ballasted insulation is laid onto flat roof waterproofing
  • Harmer Uni-Ring is positioned to support adjoining slabs at each corner, whilst maintaining open joints for fast, efficient drainage and comprises stackable units with spacers for open joint drainage when required
  • Spacers are collapsible for closed jointing and edge detailing
  • Shims are available for fine height adjustment

Materials & Finishes

  • Harmer Uni-Ring is manufactured from shallow injection moulded polyethylene
  • It is watertight and resistant to mould and freeze-thaw

Installation & Maintenance

  • Harmer Uni-Ring is quick and easy to install. Traditional bedding and grouting materials are not required
  • Once installed, paving slabs can be easily lifted for simple inspection of drainage outlets and for substructure maintenance


Do Harmer Uni-Rings allow for any slope compensation?

Harmer Uni-Rings can be stacked two high, and the Uni-Plus Rings are adjustable between 25 and 40mm, but if slope adjustment is required, the Harmer Modulock range should be used.

White House Works, Bold Road, Sutton, St Helens, Merseyside, WA9 4JG