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Brett Martin Underground 450mm Diameter Square Plastic Cover x100mm
Vendor:Brett Martin
Free delivery on Brett Martin orders over
£130£156
Regular price £62.81 £75.37Sale price £62.81 £75.37 Regular priceUnit price per£0.00
Underground Drainage | Inspection Chamber | Drainage Inspection Chambers
The Inspection Chamber category on Build4Less offers a comprehensive range of products designed for effective drainage and inspection access. This category includes various items from reputable vendors like EBP Building Products, PBSL, Clark-Drain, Floplast, and Davant, each providing unique solutions for different drainage and access needs.
What is an Inspection Chamber?
An inspection chamber is a purpose-built access point within an underground drainage system. It provides a safe opening to inspect, clean and maintain pipe runs, allowing for quick removal of blockages and routine checks without excavating the entire drain. Typically made from high-grade polypropylene or uPVC, these chambers meet UK standards such as EN 13598-1 and Building Regulations Part H.
Manhole Covers
- Locked Circular Manhole Covers: Designed for security and durability, these covers are essential for preventing unauthorised access and ensuring safety.
- Square Manhole Covers & Frames: Available in various sizes, these covers provide easy access for inspection and maintenance, suitable for both residential and commercial properties.
Gully Sets
- Yard Gully Sets with Silt Bucket and Ductile Iron Gating: These sets are ideal for managing surface water drainage in yards and driveways, effectively trapping silt and debris.
Inspection Chamber Bases
- Various Diameter Chamber Bases with Multiple Inlets: Ranging from 300mm to 450mm diameters, these bases are designed to connect multiple drain lines. They come in configurations with fixed and adjustable inlets, catering to different plumbing layouts.
- Stepped Invert Inspection Chamber Bases: These are particularly useful for deeper installations, allowing for a smoother transition between different pipe levels.
Risers and Accessories
- Inspection Chamber Risers with Integral Seal: These are crucial for adjusting the chamber height to the surface level. Available in various diameters, they ensure airtight and watertight seals.
- Davant Inspection Risers and Sealing Rings: These accessories are necessary for creating custom chamber depths and ensuring proper sealing.
Specialised Products
- Bottle Gullies and Accessories: Including raising pieces, grids, square top adaptors, and uncapped rear inlets, these are essential for managing wastewater and providing access for rodding and maintenance.
- Manhole Base Blanking Caps and Access Caps: These items are used to temporarily or permanently seal unused inlets or provide access for inspection and cleaning.
Load Capacity Options
Products in this category also vary in load capacity, catering to different environments like pedestrian areas, driveways, or heavy traffic zones.
Benefits of Using an Inspection Chamber
- Easy maintenance – Inspection Chambers: Clear blockages or perform CCTV inspections without digging up pipework.
- Leak prevention – Inspection Chambers Secure, sealed joints help keep groundwater out and waste water in.
- Durable & long-lasting – Inspection Chambers Resistant to corrosion, chemicals and frost.
- Regulation compliant – Inspection Chambers meet UK building control requirements for foul and surface water drainage.
- Time & cost savings – Inspection Chambers Fast installation with modular bases and risers reduces labour costs.
Applications of Inspection Chambers
- Inspection Chambers are used in Domestic drainage systems for new builds, extensions and garden projects.
- Inspection Chambers are used in Commercial and light-industrial underground drainage networks.
- Inspection Chambers are used in Rainwater and surface-water management, including patio and driveway drainage.
- Inspection Chambers are used in Renovation or repair work where new access points are needed.
Guidance on the Selection of an Inspection Chamber
- Diameter & Depth – Choose 300 mm mini-access chambers for shallow runs up to ~600 mm, or 450 mm large inspection chambers for deeper installations up to ~1.2 m (or more with manufacturer approval).
- Pipe Size – Match outlets to your pipework, typically 110 mm or 160 mm.
- Inlet Configuration – Fixed or adjustable inlets, depending on how many pipes converge and the angle required.
- Cover & Load Class – Select A15 for pedestrian areas, B125 for driveways, or higher ratings for trafficked roads.
- Compliance – Ensure products conform to EN 13598-1 and local Building Regulations.
Installation Tips
- Base Preparation – While Installing Inspection Chambers, set the chamber on compacted granular material or concrete as per the manufacturer’s instructions.
- Correct Falls – While Installing Inspection Chambers, Maintain the required gradient for continuous flow.
- Seal & Lubricate – While Installing Inspection Chambers, Clean and lubricate seals before push-fit assembly for watertight joints.
- Layered Backfill – While Installing Inspection Chambers, Backfill evenly in layers to avoid distortion and protect the risers.
- Final Finish – While Installing Inspection Chambers, fit the correct cover/frame level with the surrounding surface and appropriate load rating.
Why Choose Build4Less?
Build4Less provides a curated range of inspection chambers, risers, gullies and covers from trusted brands such as FloPlast, Brett Martin, Davant, PBSL and EBP. With our Price Match Guarantee, nationwide UK delivery, and trade-account benefits, you get competitive pricing and reliable service backed by expert product knowledge.
When planning or upgrading a drainage system, choosing the right access points is essential for long-term performance. Our range includes durable plastic inspection units as well as robust concrete chambers, giving you flexible solutions for every project. Whether you need compact chamber manholes for shallow runs or larger manhole chambers for deeper installations, these products ensure safe and reliable access. Designed for easy manhole inspection and maintenance, they help keep your system free-flowing while meeting UK building regulations.
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