Base Sections

Concrete base sections for manhole rings

Built to the highest standards.

AG concrete base sections for manhole rings are manufactured to comply with British Standards. Units are equipped with six special ‘knock-out sections’ that cater for inlets at various angles. We keep standard 1200mm diameter base sections in stock.

Each base unit has a 150mm thick base which allows the customer to create their own benching with the use of the various knock-outs.

Download Specification Guide

Base Sections in situ


Unit height
Internal height
Outlet / inlet openingWall thickness

1200mm Universal Base

NOTE: Standard manhole covers must have level and fully compacted granular material surrounding the units during construction stage. They are designed for D400 loading uniformly distributed through the steel manhole lid. Impact loading by construction traffic may cause structural defects.

Photo opposite: 150mm Universal Wet Cast Base and EN681 Gasket position.

Supporting Image

Available manhole base plans in 1200mm Ø bases.

of gully

Plan Type123
150mm Diameter Channel
225mm Diameter Channel
300mm Diameter Channel


AG operates a Quality Assurance Scheme to these standards to cover all aspects of production.All units are supplied with suitable lifting points.A precast concrete manhole is a strong, durable structure with its own inherent strength and does not require a concrete surround at standard depths.

More Information

All units are manufactured and tested in accordance with hEN 1917: 2002 and BS 5911-3: 2002 which, in addition to specifying dimensional tolerances, etc., clearly defines all the performance tests necessary to ensure that the product will perform satisfactorily in service.

Minimum order quantities are required for certain sizes, depths, colours, etc. Before placing an order, please speak to one of our sales teams – they’ll be happy to advise on this and any other product questions you may have.

You can reach them on:
UK: 0121 747 0202   |   Ireland: +44 (0)28 8778 8112

Do you have a technical enquiry about this product? Use the short form below and someone will be in touch.

AG Pro - Technical Enquiry
Privacy Policy

Request a sample for this product to see it in the flesh.

AG Pro - Request a Sample

Get a quote for this product & we will get in touch as soon as possible.

AG Pro - Quote Form

Why AG Professional?

Superior Quality

At AG we pride ourselves on superior quality and exceeding our customers’ expectations. Product quality is continuously being monitored and improved to provide the best quality products for our customers.

Expert Knowledge

The AG team have a wealth of experience and knowledge to share with our customers and clients. Our Technical Department is here to help – we pride ourselves in providing an unmatched level of support to make sure that all our customers get the best advice and the best possible solution for their projects. 

Unrivalled Support

At AG we believe in unrivalled support and will closely monitor and support every process from design concepts and specifications to fully indemnified engineered designs. From product supply and installation, to delivering samples, site meetings and technical support, AG will be with you on this journey.

Easy Spec

We offer a fast and easy specification service with our Sales and Specification department on hand to help with any queries. We have partnered with NBS Source which provides key specification information at your fingertips in platforms such as RIBA Product Selector and NBS Chorus. This delivers relevant product information, literature, case studies and certificates to our clients at a more effective level.

Availability / Delivery

Our team from our sales department to our despatch office work closely with customers to create a dedicated call off plan for your project. Detailed delivery planning will be scheduled around clients’ needs to ensure we provide the best customer service.

Sustainable Approach

AG have a strong commitment to the link between a sustainable environment and our local Community. In line with our Corporate Social Responsibility Strategy AG defines sustainability as the intrinsic balance between the social, economic and environmental aspects of our business operations. We have established a Net Zero Carbon team with the aim of reducing carbon emissions and are committed to producing low carbon products in our strategy.