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UNON New Assembly Hall Design - Finalist

Nairobi, Kenya

The UNON (United Nations Office at Nairobi) is one of only four United Nation's regional headquarters, along with the UN assembly halls in New York, Vienna, and Geneva.

It is the African hub for international conversation and collaboration (4,000 high-level multi-lingual meetings and conferences per year, attendance numbering up to thousands per event).

The UNON also shares its 140-acre site with the world headquarters of UNEP (United Nations Environmental Program) and UN-Habitat.

The project seeks to renew the 50-year-old conferencing facilities, reimagine the city-facing side identity of the campus, and add a new assembly hall building to provide for the ever-increasing need for global collaboration. This plan aims to create a highly sustainable and universally accessible conference facility that will represent a New African Modernism, in addition to embodying the UN's values of upholding human dignity, rights, and freedom without distinctions, facilitating international cooperation, and bettering standards of life in larger freedom.


The KSP-led design team was tasked to submit a concept design for the new assembly hall within a 10-day period. The team had been developing design criteria and approaches prior to this task. The team's design criteria centered around restoring the native ecology (adjacent Karura Forest together with the natural hydrology and native soil) and blending with nature. Also crucially considered was to provide meaningful varieties of inspiring places to meet and collaborate, in, out, and around the new assembly hall, emphasizing comfort, community, identity, health, and a sense of wellness. Together with the use of local materials and methods, we determined these design principles to be part of the core constituents that define New African Modernism.

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The site of the project bridges between the metropolitan Nairobi area and the ancient Karura Forest. The modern perimeter of the forest is marked by forest edge effect (drier conditions, lighter colors, confluence of invasive species, bite-mark edge profiles) indicating the progressive deterioration of the forest boundaries caused by urbanization. The project aims to reverse this effect for the first time and let the forest advance forward, as its regrowth balances with the UNON campus as a symbiont on the site. This effort will enable suppression of invasive species, proliferation of native flora and fauna, natural waterways restoration, and native topsoil protection.

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In response to the need for a regenerative campus, the new assembly hall is conceived as the native landscape gently rising up in a spiraling incline. The benefit of this approach includes:

  • Retention of native topsoil (the soil removed for construction will be returned to its original location above and around the building)
  • Maximizing permeable surfaces for aquafer recharge and fresh water run-off mitigation
  • Superb interior climate control (soil's specific heat is ideal for daytime cooling effect from heat absorption and natural insulating properties)
  • Natural ventilation opportunities
  • Many varieties in places-of-gathering adjacent to the assembly functions
  • Biophilic amenities
  • Universal access


The existing conferencing facility features a central courtyard. It has been a beloved space, but the stair-connected 30 feet floor height change and the lack of solar control made it very hot, with cumbersome accessible routes. The new assembly hall proposes a reimagining of the existing courtyard, as it is the center of the numerous conferencing functions including the new assembly hall. The proposed concept turns the floor height challenge into a gradually cascading open air garden. The integrated circulation provides a pleasantly meandering path within 1:20 slope for universal access. For those in a hurry, a direct route discreetly cuts through the landscape by means of integrated steps. The solar shades and lush perimeter planting creates a pleasant outdoor climate for informal gathering functions. The seats and bleachers made of native stone and recycled wood material blends with the local plant life creating distinct varieties of places suited for conversations, collaborations, or personal space.

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The new assembly hall is located at the far end of the courtyard, but situated to allow people to see Karura forest in harmony with the blended architecture of the new assembly hall. The building in the forest view will be experienced as a new identity at UNON.

The new assembly hall will be perceived as part of the courtyard, intuitively accessible, expanding the footprint of the conference experience beyond the immediate confines of the new assembly hall.

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The 1,500 seat capacity assembly hall is designed for connection and communication, heightening a sense of connectedness. "If you can's see, you can't hear" was one of the key design principles, and utilizing technology as a window rather than a barrier. The ovoid plan provides the best sight lines to the dais, from the very front to the far edges of the seating arrangements, maintaining a sense of inclusion wherever the delegates are seated.

The acoustic properties is paramount. The angled walls, microperforated acoustic wood panels, and even the ceiling light baffles enhance the acoustic experience helping the clarity of acoustic communication and providing a comfortable soundscape.

Ample natural daylight is provided through the various skylights and clerestory windows. The ceiling baffles balance the natural light mitigating glare while providing a sense of passage of time as the skylight course through the circadian cycle. This provides time awareness and visual comfort that contribute to effective thinking and decision making. The clerestory windows also allow direct view out connecting the delegates directly with nature as Karura forest matures around and over the assembly hall.

The assembly hall also utilizes displacement climate strategy powered by a passive heating and cooling system that utilizes underground labyrinth cooled air and solar chimneys on the roof.

The assembly hall accommodates delegate layouts (delegate desks, support staff seating, conference technologies), translator booths, and media/spectator balcony.

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The new assembly hall at the UNON is a highly practical application of the most human approach to a building that can heal and regenerate the ecology. It is a testament to a human design principle that aims to be cost-effective, highly useful, regenerative, and biomimetic (like nature) all at the same time.

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