The Kenya Railways Headquarters Building

The Architect

Sir Herbert Baker was born on 9th June, 1862 in Cobham, Kent in England. He studied architecture in London. He arrived in South Africa in 1892. Sir Edward Grigg, Governor of Kenya from 1925 to 1931, invited Baker to visit Kenya in 1925. His first building in Nairobi was the Nairobi European School (now Nairobi Primary School). Other impressive buildings in Nairobi designed by Baker and completed with his assistant, Jan Hoogterp, include the Law Courts, the Kenya Railways Headquarters building and the Government House (now State House).

His other works elsewhere include the design of the South Africa House in Trafalgar Square, London. The India House in the Aldwych. In South Africa, he directed the rebuilding of Cecil Rhodes’ house Groote Schuur (now the residence of the President). He went on to design St George’s Cathedral, Cape Town and, most notably, the Union Buildings in Pretoria. In New Delhi, he worked with Sir Edwin Lutyens on the design and construction of the ad­ministrative buildings of the government of India.

The Building

The Kenya Railways Headquarters building is located in the Southern part of Nairobi’s CBD, off Haile Selassie Avenue and opposite the Railways Bus Station. The whole complex consists of two blocks, the earlier block (shaded) by Baker plus another later block to the West which was done years later.

Environmental Design Considerations

Provisions for Thermal Comfort.

1. Site Layout

i.) Building orientation: The building’s front side faces to the Eastern side with the back facing to the West. This helps shield the front facade (the building’s main facade) from the hot Western afternoon sun.

ii.) Plan layout: Servant spaces (toilets, and circulation) are placed on the Western side. This is the most affected by the western sun leaving the sheltered eastern side for office use. This way, the servant spaces act as a buffer shielding the master spaces from the hot afternoon sun.

Building form

i.) Sun shading circulation corridor: The corridor on the Western facade provides shading to the office spaces.

ii.) Sun shading elements: The windows on the Eastern facade are well sun shaded by the use of concrete balconies.

Openings

i.) Small window area percentage as compared to the wall area: The Railways headquarters exhibits a relatively small window area compared to the wall surface. This reduces the amount of heat build-up due to direct solar radiation.

1. Construction materials

i.) Reflective exterior finish: This helps reflect much of the sun’s radiation reducing heat build-up by cutting down on the buildings solar load.

ii.) Thick walls: Most of the walls used are 300mm thick with some 600mm thick. This provides a wider time-lag keeping the interiors cool for most of the day.

1. Use of planters

Baker created planters in the courtyard. These provide a cool environ­ment due to a combination of evapotranspiration, reflection, shading and storage of cold.

Use of water for cooling

Several water features (fountains and pools) were provided in the court­yards. These acts as heat sinks, cooling the building mass by radiant cooling. Sprayed water from fountains evaporates at a higher rate cool­ing the air by evaporative cooling. Air passing over the water further cools the building.

iii.) Provisions for Day-lighting.

1. Building Layout

i.) Use of Courtyards: Baker used courtyards to light the other­wise very deep plan. The walls surrounding the courtyards are painted white increasing reflectance of light into the building.

Building materials

ii.) Interior finishes: The buildings interiors are painted white which allows for the propagation of natural light for better distri­bution.

iv.) Provisions for Natural Ventilation.

1. Building Layout

i.) Cross ventilation: The buildings plan allows for through air movement from the eastern facade and out through the western facade.

ii.) Use of the courtyard: Air gets into the building through the courtyard

Eric Loki David, Architect Mphil. (Environmental Design in Architecture) Cambridge, B.Arch (Hons) Nairobi, LEED (Green Associate) MAAK (ED) is the author of this article and is a contributor to BuilDesign Magazine.