Jan 15

Jan 15 Montague Gardens | Commercial alterations

This commercial project is an addition to an existing factory in Montague Gardens, a dynamic business suburb in Cape Town. The scope of the project consisted of creating the structure for the new section using the Cobute Precast decking and beams; the stairs connected the existing ground floor to the new one. The main advantage of using these integrated solution is casting both Cobute elements in one pour, greatly reducing concrete and time costs as well as reducing cracking and cold joints.

For this project, the rectangular columns were cast in-situ using the reusable shutters for in 100% recycled ABS Geotub Panel (350 x 350 mm); this showed the perfect interaction between the Cobute and Geoplast sustainable building systems.

Precast panels and beams in place before the panels are installed.

Cobute Precast Decking

Cobute supplied 800 m² precast decking for the first-floor slab and its concrete shutters for beams to support the structure.

The decking system designed and patented by Cobute consists of precast concrete ribs and interlocking panels. While the ribs height changes according to the thickness of the slab, the precast panels come in a standard size. Cobute manufactures slabs of 10 different thicknesses in increments of 25mm, and 15 different reinforcing combinations to suit the Engineer’s design.

The Cobute decking has an R Value (Thermal Resistance) of 0.4889 for a 250mm thick slab. The slab holds a fire resistance certificate of 150 minutes for a 230mm thick slab. The use of polystyrene void formers is one of the innovations of the Cobute decking system; these blocks ensures the lightweight of the system, equal to 97kg/sqm before casting. Moreover, the use of polystyrene ensures:

a reduction of approximately 50% of the total amount of concrete needed
a much greater variation in slab thickness without any undue increase in the
in-situ concrete
a lightweight structure
an easy service distribution
a contribution to thermal and acoustic insulation.

Cobute decking system during the concrete pour.

Cobute Precast Stairs

The Cobute Precast Stairs is custom-made to fit individual specifications as per engineer’s designs. The stair system delivers an empty shell consisting of girders, ribs, panels and risers. Once the concrete is poured, the empty shell is filled and the treads are formed.