Precast Concrete Adjusting Units have been manufactured by MPA precast Drainage Members for over 30 years. Formerly known as Cover Frame Seating rings, the name being changed for consistency with European Standards were specified in BS5911-200 in 1994 demonstrating a proven track record. The most recent issue being BS5911-3:2022 requires the units comply with all current relevant standards for concrete such that a 100 year design life can be demonstrated.
A major benefit is compliance. All principal UK specifications state BS5911-3:2022 as a requirement for the units. They are specifically detailed in the ‘Design and Construction Guidance for foul and surface water sewers’ published by Water UK and ‘The Manual of Contract Documents for Highway Works (MCHW)’ published by The Department for Transport.
MPA Drainage manufacturers are required to have third party certification for BS5911-3 with BSI permitting kitemarking and UKCA marking. This allows a Kitemark certificate to readily demonstrate compliance with the above specifications without any approval process.
In addition to all standard sizes for cover frames, corbel units are available allowing flexibility for use with ladders.
In summary Precast Concrete Adjusting Units are a proven option with long term durability and full approval in UK Specifications.