Big J Inspection Chamber

A new concept in chamber design. A two-piece unit where the base is integral with the sides. The required pipe openings are cast-in at any desired position, no brickwork or shuttering is required, no awkward holes to be cut. Big ‘J’ chambers are supplied complete with galvanized step irons and all necessary fixings and come complete with heavy duty cover slabs and manhole access. All units have special lift points cast.

Machine-made reinforced concrete sections to BS.5911 part 2 are fitted on the lid of the Big ‘J’ chamber to extend the opening to ground level. Standard 600mm x 600mm galvanized 17 tonne GVW pressed steel manhole covers cast into a 100mm thick concrete surround are available to fit these units.

  • Made to order – Leadtime 2-4 weeks.

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BIG ‘J’ SIZE (D) 1220 x (W) 1070 (D) 1630 x (W) 1070 APPLICATIONS
Height (H) of basic chamber 810mm
1120mm
1420mm
1735mm
2030mm
2340mm
810mm
1120mm
1420mm
1735mm
2030mm
2340mm
Manhole

Piped Ditch Inlet

Tumbling Bay

Flow Meter Box

Pumping Sump

Siphon Pit

Effluent Storage

Maximum O.D. of pipe recommended 830mm

Product information.

KEY BENEFITS.

  • Precast in controlled factory conditions with steel moulds to guarantee accuracy
  • Faster, cheaper and safer than casting on site.
  • ECO 1 sustainable concrete mix as standard.
  • ECO 1 Ultra option available

 

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installation ADVICE

expert tips and best practices.

Depending on site conditions, it is recommended that these units should be bedded on 100mm of ready mixed concrete. Each section should be hoisted into position separately ensuring that rebated joints properly locate. Use the galvanizes bolts through the fixing brackets at each side to keep the units together during backfilling. Do not over tighten. The drain pipes should just enter the chamber or remain flush on the inside. Make good the voids around the pipes with cement mortar. Make sure the opening in the cover slab is located over the side with the step irons. Rectangular inspection chamber sections can be positioned over the access hole to extend the chamber to required ground level (see below) or full sized extension sections are also available.

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