Access Chambers

Access Chambers & Inspection Chambers | Cubis STAKKAbox

Access Chambers | STAKKAbox™ from Cubis

STAKKAbox Chambers

STAKKAbox access chambers manufactured by Cubis are a range of modular, structural and sectional preformed access chambers manufactured from modern technology polymer materials – STAKKAbox chambers provide significant advantages compared to conventional brick built access chambers. The chambers are lightweight but durable and deliver impressive labour productivity gains, time saving benefits and associated cost reductions to the installation contractor.

Specify STAKKAbox Chambers

Cubis’ STAKKAbox™ access chamber systems are adaptable to the unique requirements of each construction site. This means ordinary site tools can be used to retrofit chamber systems around existing networks by drilling duct entries or cutting the chamber sections horizontally. The seamless integration across the Cubis chamber product range enables the construction of bespoke systems that significantly reduce costs of access chamber construction through time savings. Cubis’ chamber options and accessories range allows installers the ability to simply place, connect ducts, backfill and walk away.

See Our Blog: Which Access Chamber Can Be Built Faster?

Access Chambers

Brick Built Footway Access Chamber (Traditional) VS   STAKKAbox™ Modula Access Chamber (Modern Technology)

Types Of STAKKAbox Access ChamStakkabox Sectional Access Chambersbers


Sectional Access Chambers use individual STAKKAbox sections, which are stacked to offer flexibility and required chamber depth. Each ring section interlocks with the units above and below. Manual lifting of this chamber is safe due to the lightweight properties of each section.

Stakkabox Modular Access Chambers


There are a variety of options for clear openings of chambers. Access chamber sections are available in ‘solid rings’ or as part of a system of modular component parts.

Stakkabox Structural Access Chambers


Structural access chamber use twin walled STAKKAbox™ sections to provide a strong, yet lightweight product. Complete assembled chambers feature horizontal and vertical ribs to allow for efficient loading.

Should you require any STAKKAbox technical, specification or commercial support please do not hesitate to contact us and discuss your requirements.

See our range of STAKKAbox access chambers below.

Chamber  ULTIMA & Connect  Fortress  Modula  Quad RapidSTACK Hydrant
Flat Pack? Yes Yes Yes No Yes No
Section Depth 150mm 150mm 155mm 150mm 150mm 25/75mm
Maximum EN124 Loading 90 Tonnes (F900) 40 Tonnes (D400) 40 Tonnes (D400) 12.5 Tonnes (B125) 40 Tonnes (D400) 40 Tonnes (D400)

Ultima Connect Chambers

Access Chambers

ULTIMA Connect | The Next Generation in Chamber Access Systems

Variability in Size

ULTIMA Connect offers a huge range of chamber dimensions due to the large number of standard sections and the variability offered by the ULTIMA Connect system manufactured by Cubis.

Flat Pack Option

STAKKAbox ULTIMA can be shipped ‘flat packed’ to reduce shipping costs. A large chamber, as used on power stations or waste water treatment works, could be reduced to a number of pallets rather than occupying an entire transport vehicle or lorry.

Flexibility in Construction

Cable duct entries can be quickly and safely formed on site. Overbuilding or benching is easily achieved. Fine top level adjustment is possible by horizontally cutting the top section of the chamber.

Chemical Resistance

GRP outperforms traditional construction methods for chemical resistance during its buried life, resulting in a product that offers longer installed life.


Due to the sectional twinwall design and the GRP material, most ULTIMA Connect 150mm deep sections fall under 25kg in weight, making them suitable for a single person lift under manual handling regulations.

Fast & Easy to Install

ULTIMA Connect chambers are significantly faster to install than conventional alternatives, with complete installations typically taking up to one hour. This results in reduced costs for the installer. Only the largest sizes in the range require specialist equipment or plant in order to install the chamber.


ULTIMA Connect offers the ability to offset joints between sections to provide a strong brickwork effect improving side wall performance.

Smooth Outer Walls with Lip to ‘Key In’

Gaps in the outer wall will negatively impact the effectiveness of compaction around the chamber. STAKKAbox™ chambers have smooth outer walls and an outer lip which keys into the backfill.

Access Chambers | Project London Olympic Stadium Redevelopment: ULTIMA Connect

STAKKAbox ULTIMA Connect Access Chambers

STAKKAbox ULTIMA Connect Access Chambers | The Nemo Link® is a truly international collaboration in the construction of a High Voltage Electrical Interconnector between the UK and Belgium’s electricity grids. Consisting of subsea and underground power cables connected to converter stations within each country, the HV cables distribute electricity in either direction. Cubis Systems was selected to provide a HV receiver and diversion chamber system – this resulted in the delivery of 152nr 1.5m up to 2.6m ‘flat pack’ STAKKAbox ULTIMA Connect chamber systems for construction in-situ on site.

The flat-pack design of the ULTIMA Connect system permitted rapid installation of the chambers around the cable duct bank with labour productivity savings and benching over underground services and creating cable duct entries for the 33kV high voltage power cables.

Access Chambers | STAKKAbox

Overview of Access Chambers Manufactured by CUBIS

  • ULTIMA Connect Access ChamberCubis Access Chambers
  • ULTIMA Access Chamber
  • Fortress Access Chamber
  • Modula Access Chamber
  • Quad Access Chamber
  • Hydrant Access Chamber
  • RapidSTACK™ Access Chamber
  • MONObox Access Chamber

➡ Should you require any technical support and specification guidance please do not hesitate to contact Thorne & Derrick Sales Team.

For the protection of MV & HV (Medium & High Voltage) underground cables pulled and laid into trenches please refer to our range of cable protection covers for 11kV, 33kV, 66kV, 132kV and 400kV cable networks using Tapetile and Stokbord ranges.

STAKKAbox™ ULTIMA Access Chambers STAKKAbox™ ULTIMA Connect Access Chambers STAKKAbox™ Modula Access Chambers STAKKAbox™ Quadbox Access Chambers STAKKAbox™ Fortress Access Chambers
STAKKAbox™ ULTIMA Access Chambers STAKKAbox™ ULTIMA Connect Access Chambers STAKKAbox™ Modula Access Chambers STAKKAbox™ Quadbox Access Chambers STAKKAbox™ Fortress Access Chambers
STAKKAbox ULTIMA offers a high strength flexible access chamber – the GRP chambers overcome sidewall loading concerns and are installed typically on highways and trackside rail projects. STAKKAbox ULTIMA Connect chambers provide additional flexibility without compromising strength – features same twinwall design as the standard ULTIMA chamber but built from combining multiple parts. STAKKAbox Modular access chambers are modular and structural preformed chambers permitting quick and cost efficient construction of access chambers with excellent build quality and site safety. STAKKAbox Quadbox chambers are a range of modular and structural preformed chambers available in size options 102, 104 and 106. The access chamber is approved for use on BT Openreach networks. STAKKAbox Fortress chambers are moulded from HDPE with excellent weight to strength properties – each section is internally ribbed to provide enhanced load bearing performance.