Accra, Ghana

New Lands Commission Accra, Ghana

3TI Progetti Italia Ingegneria Integrata SPA, ATENASTUDIO, Cityförster

The project objective is to design, construct and equip a new head office and regional office building for the New Lands Commission in Accra. The Government of Ghana has allocated the New Lands Commission a plot of 11,73 acres in Accra. The project is financed in parts by the Government of Ghana and a grant from the Federal Republic of Germany through KfW Entwicklungsbank (KfW). The headquarter of the New Lands Commission aims at symbolizing the new spirit of transparency and efficiency. KfW in coorperation with the Government of Ghana aims at financing an administrative building covering all units, divisions and agencies. This building being of an important symbolic standing shall be undertaken as a building in a standard appropriate to accommodate the New Lands Commission and to present a monument of its own. It shall be of representative character. The office spaces will be of a flexible open plan nature to allow for the dynamic nature of the Commissions development and in accordance with changing technical requirements of office usage. The building has been designed environmentally friendly, using renewable energy sources and according to the tropical requirements. The buildings basic shape, a rectangle oriented to the compass axes is a response to the tropical climatic conditions. The long sides of the building face north/south, the short sides face east/west, thus few areas are exposed to the lower angle sun radiation in the morning and evening that are difficult to shade. The building is lifted from the ground, creating a large shaded area underneath and al¬lowing for the landscape to flow under and inside the building. This, in combination with landscaping measures creates a pool of cooler and cleaner air that can be used to ventilate the building and helps to avoid the either humid or dusty direct winds from south and north. Nevertheless the building will have to be equipped with a complete air conditioning system, to guarantee comfort inside the offices when a natural climate control would not be effective. Our aim however is to contribute as much as possible to a comfortable climate by natural means. The shading system of the envelope have been differentiated in relation to solar exposition. A facade of bamboo modular panel will provide different kind of screens: on the facade fac¬ing south they will be closed on the top, side closed on the eastern and western ones and opened towards the sky, to catch as diffuse light as possible, on the northern facade. The External panel will also act as barriers to the unfavourable desert or Atlantic winds. Except for the Harmattan and Monsoon seasons, thus in seasons with milder climate conditions, a natural passive control of inner comfort conditions can be foreseen and the whole architecture has been conceived in compliance with this topic. Ventilation patios provide naturally air-flows due to a combination of chimney thermal driven effect and Venturi acceleration effect, related to open-able windbreak that catch external winds on their top if opportune. When external climate conditions are not appropriate to let air enter the offices, natural airflows will be exploited to ventilate the circulation space that is always shaded and without thermal loads from permanent presence of lights, equipment or employees. When external temperatures and humidity are acceptable, the windows on the facades will lead fresh air inside the offices, providing cooling and the air changes required. Investigation about local materials have also led to individuate “lightened earth”, a modern evolution of the traditional “torchis”, being the most insulating mass and transpiring material, appropriate to ensure a high efficient external envelope: this technique provides prefabricated panels made up by a mixture of ground with “inert” consisting of vegetable fiber or lightweight materials. At Night time, when temperatures are significantly lower than during the day windows will be opened to let air enter the building and cool the structural masses that store heat during the day. The landscaping of the site is as much an ecological machine as it is a pleasant spatial experience: it integrates water-management and security features into all its spatial elements. A system of hills, planted with helophytic plants that can be used for the treatment of waste water, will provide clean water for irrigation and cooling of the site. Combined with rainwater harvested from the roofs of buildings this water is collected and gradually released into the large pond underneath the main building.

Europaconcorsi Beta

New Lands Commission Accra, Ghana