PLANNING was approached by the client because of the way in which we had solved the challenges of Nairobi’s Lonrho House, a tower constructed over an existing three storey building on a restricted site.
I&M Bank Ltd required a tower that would hold both office and retail space on their spatially restricted city center plot. Detailed cost and benefit studies were carried out at early design stages for several building options, keeping in mind existing buildings and busy roads on all sides and the need to build over the entire site.
The design option agreed upon was a three-level atrium opening onto Kenyatta Avenue and Muindi Mbingu Street. This gave pedestrians access to podium shops and offices in the tower above. The Atrium concept was successful in visually and functionally separating the retail from the offices, giving a visual impression of the tower rising from the ground (podium). The Client felt that this option gave him the best commercial advantages.
The office floors are designed so that natural cross ventilation is possible. Staircases, elevators, and lavatories are on the westerly side of the building to shield offices from uncomfortable heat gains and glare from the afternoon sun. Limited building space meant a heat reflective glass cladding system would have to arrive on site in fully finished sections ready for assembly. All floors are of a composite construction, where floor slabs were precast off-site and lifted into position, thereby minimizing on-site concrete mixing and material storage.
This area of the City is heavily polluted with noise and car exhaust fumes, requiring mechanical air handling for the building. 100% standby power provision and water storage in the basement ensures the building can survive temporary power and water supply failures.