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450mm to 350mm Manhole Chamber Reducing Ring

450mm to 350mm Manhole Chamber Reducing Ring

Reducing ring for 450mm chamber openings, designed to reduce the clear opening to 350mm. Suitable for new chamber builds or retrofit upgrades to meet restricted access opening requirements.

Lightweight polypropylene construction with snap lock fitment for quick installation and secure seating.

£27.30
£27.30
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CD 499

Expected delivery date:
06 Jun Estimated arrival via standard delivery within 2–3 working days. Express delivery 1–2 working days available.

450mm to 350mm Manhole Chamber Reducing Ring

450mm to 350mm Manhole Chamber Reducing Ring

Description

The CD 499 Manhole Chamber Reducing Ring is designed to convert a 450mm chamber opening down to a 350mm clear opening. It is commonly used where access chamber openings need to comply with Part H of the Building Regulations for deep access chamber restriction.

Manufactured from polypropylene, this reducer ring offers a lightweight, non-rusting solution that is easy to handle and install. It can be fitted during a new chamber installation or retrofitted to compatible existing chambers and covers where opening size needs to be reduced.

The integral snap lock feature helps provide secure fitment once installed, reducing movement in service and making installation quicker than loose insert alternatives. This makes it a practical choice for domestic drainage systems, driveways, pedestrian areas and inspection chambers using compatible covers.

Manufacturer data confirms compatibility with CD 452, CD 456 and CD 450SR/46SL access covers. The multi-fit application allows use across pedestrian and driveway cover installations where suitable supporting components are already in place.

Always confirm chamber size and cover compatibility before ordering. This reducing ring is intended for 450mm chamber systems and is not a universal fit for all chamber brands or diameters.

Key Features

Reduces 450mm chamber opening to 350mm clear opening

Helps meet Part H deep access chamber restriction requirements

Lightweight polypropylene construction

Integral snap lock for secure fitment

Suitable for new installs or retrofit upgrades

Non-rusting design for underground use

Material Composition


Manufactured from polypropylene (Grade AP9). This material provides a durable, corrosion-resistant chamber component suited to underground drainage environments.

Product Specifications

SKU: CD 499
Product type: Chamber reducing ring
Material: Polypropylene (Grade AP9)
Clear opening: 350 mm diameter
Overall diameter: 453 mm
Depth: 61 mm
Approx. weight: 1 kg
Colour: Black
Fitment type: Integral snap lock
Compatible covers: CD 452, CD 456, CD 450SR/46SL
Made from recycled material

Manhole Cover Accessories

About this collection

Manhole Cover Accessories

Manhole cover accessories are designed to assist with the installation, lifting and maintenance of access covers and inspection chamber covers. Our range includes practical parts such as lifting keys, replacement components and chamber accessories used across domestic and commercial drainage systems.

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FAQs

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What does this reducing ring do?

It reduces a 450mm chamber opening to a 350mm clear opening for compatible chamber systems.

Why would I need a reducing ring?

It is commonly used to meet Part H Building Regulations requirements for deep access chamber restriction.

Can this be fitted to an existing chamber?

Yes. It can be retrofitted to compatible existing installations as well as used on new builds.

Will this fit any 450mm chamber?

No. Always check chamber and cover compatibility before ordering, as not all systems use the same dimensions.

Is it suitable for driveway use?

Yes, when installed within a compatible chamber and cover system rated for the required loading.

Customer reviews

4.86 ★ (287)
450mm to 350mm Manhole Chamber Reducing Ring

450mm to 350mm Manhole Chamber Reducing Ring

£27.30
£27.30

Customers are saying

4.86 ★ (287)
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