Manhole Boxes

Manhole BoxShore & Pour offer three sizes of Manhole Box 2.5m, 3.0m, and 4.0m square. The size refers to the external dimensions of the box, the internal dimensions are shown in the table below.

For square configurations the boxes are supplied with non-adjustable struts, but these can be replaced with adjustable spindle type struts if a rectangular excavation is required.

The fixed struts come in two slightly different lengths. The blue struts are 20mm longer than the yellow struts, and should be placed in the lowest position. This gives the panels a slight toe-out configuration to compensate for deflection due to ground pressure. Only yellow struts are used in the top extensions.

If adjustable spindles are used, the lowest struts should be extended slightly more than the upper ones to give the same effect.


  2.5m Box 3.0m Box 4.0m Box
Panel Length (m) 2.5 3.0 4.0
Return Length (mm) 600 600 600
Base Panel Height (m) 2.5 2.5 2.5
Top Panel Height (m) 1.5 1.5 1.5
Panel Thickness (mm) 100 100 100
Assembled Base Weight (kg) 2560 2858 3465
Assembled Top Weight (kg) 1815 2015 2440
Clearance Under Struts (mm) 1.44 1.44 1.44
Clearance Between Struts (mm) 2130 2630 3630
Fixed Internal Dimension (mm) 2053 2553 3553


Recommended Box Sizes for Standard Manhole Rings

These figures are based on rings made to BS5911 with 150mm of concrete cover.


Manhole Ring Size (mm) 2.5m Box 3.0m Box 4.0m Box
675 Yes    
900 Yes    
1050 Yes    
1200 Yes    
1350   Yes  
1500   Yes  
1800   Yes (tight!)  
2100     Yes
2400     Yes
2700     Yes



Fixed Spindles
Fixed Spindles

Spindle Holder & Pins
Spindle Holder & Pins

Maxi Spindle
Maxi Spindle

Box Connector
Box Connector



Download information sheet (PDF)



See also : Manhole Brace Frames, Manhole Shutters, Trench Boxes, Safety Barriers





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TEL : 01844 353790

FAX : 01844 354830