From Earth to Education: A Sustainable Approach to Climate Resilient School Design in Rural Zambia

AAU - Aalborg University, Denmark

Idea projektu

This thesis proposes the design of a secondary boarding school in rural Zambia, in which different strategies are integrated to make the design climate resilient as well as providing a high-quality learning environment. The project is designed with a community driven approach, ensuring the needs of the users are fulfilled. An additional focus area is the use of simple construction methods from locally sourced materials, enabling the local community to take part in the building process. Furthermore, this thesis examines the relationship between a comfortable indoor climate and the environmental costs associated with achieving it in the context of a developing country. The final design seeks to reach a balance between environmental impact, indoor climate and user comfort, offering a solution that is both contextually relevant while still providing the design with architecturally qualitative spaces. Ultimately, this work advocates for a thoughtful approach to school design. An approach that embraces environmental responsibility, strengthens community engagement and involvement, and creates an educational environment through climate-conscious decisions.

Popis projektu

The final design proposal integrates both quantitative data and qualitative insights. Passive design strategies were employed to enhance the indoor climate, with the majority of materials sourced locally to lower environmental impact and respect the local architectural expression. The school layout consists of multiple building clusters inspired by traditional Zambian function layout. These clusters are connected by a continuous overhang and raised floor deck, providing sheltered circulation while offering protection against flooding. At the heart of the campus lies a central social gathering space, providing a multipurpose space where the school community and experience can flourish. Ultimately, this thesis presents a holistic design, a school building that considers the climate, respects local material and aspires to provide a high-quality learning environment for its users. by a continuous overhang and raised floor deck, providing sheltered circulation while offering protection against flooding. At the heart of the campus lies a central social gathering space, providing a multipurpose space where the school community and experience can flourish.

Technické informace

Construction:
The final construction detail illustrates a climate-responsive and resource-efficient building envelope by the use of local and natural materials. The roof consists of multiple layers that prioritize thermal insulation and resilience against heavy rainfall. It consists of an aluminum corrugated sheet supported by spruce battens and plywood, insulated with 280 millimetres of kenaf fibre, and finished with an interior bamboo layer for improved acoustics and aesthetics. The outer wall combines ICEB with a 120 millimetres straw bale core as insulation. The raised floor is insulated with 140 millimetres of straw bales and topped with OSB boards, which is supported by a ventilated stone foundation. A capillary barrier and an additional 120 millimetres of kenaf insulation below the foundation enhance thermal performance. These components alltogether create a durable and flood-resilient structure with low environmental impact.

Daylight:
The final window proposal presents a wellbalanced solution to daylight access, ventilation, and façade aesthetics. The windows in the final
design have a window to floor ratio of at least fifteen percent in all rooms and go up to twenty percent where it is more needed. The final design makes no use of shutters, as this was proven to have a minimal impact on thermal environment with a negative effect on daylight levels. The absence of shutters allows for a more consistent distribution of daylight, as reflected in the radiation maps. The UDI value of 76% and sDA of 89.3% confirm strong daylight autonomy in the final design, proving sufficient daylight levels for a learning environment.

LCA:
The life cycle assessment of the final design reveals how material choices and transportation impact carbon emissions. Among the construction element, the stone foundation demonstrates the highest GWP, with a significant portion coming from transportation which is directly related to the distance and material density. Despite being a heavier material option, the stone is locally sourced and resilient
to flooding, making it a sustainable and durable choice in the long run. The wall has the second highest environmental impact, primarily due to the cement content in the ICEB mixture, despite it making up just five percent of the composition. Its presence significantly contributes to the structure’s overall GWP. In contrast, the roof and floor have the lowest GWP. The floor’s wooden structure with straw insulation, coupled with earth tiles, minimizes carbon emissions. Similarly, the roof integrates kenaf insulation, bamboo, and aluminium to balance
climate resilience and acoustic performance while maintaining a low environmental footprint.

Adaptibe thermal comfort:
The graph illustrates the percentage of hours within the adaptive thermal comfort (ATC) range, highlighting the improvements made in the
final design. The final design achieves 87.9 percent of hours within the comfort range of category three, demonstrating the effectiveness of
material and design modifications in optimizing indoor climate conditions. The rise also reflects the embodied carbon in additional materials used to achieve better comfort levels, but the improvements in ATC justify this trade-off by ensuring a more comfortable indoor environment. Ultimately, the final design prioritizes thermal comfort, significantly enhancing the indoor climate without excessive environmental costs.