The Nest, Derby Road

Dice worked closely with the design team to overcome numerous challenges encountered during early design stages of the project’s delivery. This included poor ground conditions, which impacted upon the piled foundation solution and contiguous piled retaining structure, which was installed to support the public highway to Wollaton Street at the rear of the site. The client’s request to incorporate both a masonry and timber frame superstructure also created numerous design complications associated with disproportionate collapse, due to the development being five-storeys in height and therefore falling into a higher risk category (2b).

The 5-storeys of masonry were constructed off a grid of steel beams at first floor level. The beams were positioned generally on the load bearing, blockwork wall lines. Proposals also showed 4 steel columns within the retail space which created long spans for the steel beams relative to the high load coming down each of the blockwork which were rationalised with additional columns. An in-situ concrete deck at first floor level was introduced in order to restrain the floor beams.

Given the high beam loads, a timber deck was found to not be sufficient to restrain the beams and therefore inefficient over the spans required. The introduction of a concrete deck not only restrained the beams, it also enabled a composite action which reduced the steel tonnage by 20%. The concrete deck also provided a robust working platform to commence the building of the load bearing walls above, each centred on the beam lines.