Optoppen refers to the concept of adding prefabricated structures on top of existing rooftops to maximize space efficiently.
Myy project focuses on addressing housing demand challenges by exploring lightweight housing extensions on existing buildings.
My project focuses on addressing housing demand challenges by exploring lightweight housing extensions on existing buildings.
Housing Shortage History
Why are housing extensions necessary?
In Spain, the increasing housing demand—partly due to long-term immigrants willing to pay higher rents—is significantly affecting students and young professionals. This creates a need for affordable housing solutions.
Spain Housing Policy
Barcelona opportunity
State of the Art (SOA)
I analyzed existing buildings to understand feasible approaches for rooftop extensions.
Research methodology
AIM
Demography Focus
This solution aims to provide students with affordable and accessible housing.
Site Selection
My research is in Barcelona, a city with significant potential for rooftop extensions. My analysis focused on Sant Martí, where I identified multiple buildings with the capacity for vertical expansion.
I selected a specific building that allows for a two-story extension. This building has two existing staircases, making it convenient to integrate the new structure seamlessly.
My analysis focused on Sant Martí, where I identified multiple buildings with the capacity for vertical expansion.
I selected a specific building that allows for a two-story extension. This building has two existing staircases, making it convenient to integrate the new structure seamlessly.
Design
&
Structural Approach
I designed a scaffolding-based structure, which ensures quick and efficient assembly on-site. The spatial organization aligns with the building’s existing functionality:
Functional Layout
The ground floor is a shared community space—a central hub where residents can cook, relax, do laundry, and socialize.
The first floor consists of modular pods designed to accommodate 18 students, with each pod shared by two individuals.
Axo sections
Materiality & Construction System
The structural system is composed of beams connected using spacers, with cables running through all the modules. The material composition includes:
• Inner skin: 3mm plywood
• Outer skin: Shingles
• Core insulation: Cardboard layers placed between the inner and outer skins
Assembly Sequence (one Module)
The structure segregated down into nine pieces, and each structure consists of the Main beams connected with the spacers
Assembly Sequence on-Site
• Scaffolding structure is first assembled on-site.
• Prefabricated modules are then slid and pushed onto the main scaffolding beams.
• Interlocking spacers secure the modules together by connecting the outer beam frames of adjacent modules, ensuring structural stability.
Manufacturing & Prototyping
For the prototype, I experimented with kerfing techniques to bend wood without heating it:
• At 1:50 scale, the wood cracked at 30 degrees.
• At a 1:1 scale, I increased the number of kerfing cuts and improved the technique. Initially, the bending was not reaching a perfect 90-degree angle, but after refining the Third Main beam Kerfing pattern, I successfully stabilized the structure.
To achieve this precise bending, I used two mold techniques. Three different iterations were tested:
• Fully glued with veneer
• Glued only within the kerfing gaps
• Without glue inside the kerfing gaps, using veneer glue only (which proved to be the most stable).
Cardboard Layering
Next step
My next objective is to work with full-size pine wood (2.4m – 3m) without cutting it into smaller sections. By kerfing and bending the entire piece, I aim to optimize the manufacturing process and reduce assembly time.
Conclusion
This project explores the potential of modular rooftop extensions as a scalable and sustainable approach to address urban housing needs. By leveraging prefabrication, lightweight materials, and efficient construction techniques, we can create affordable, adaptable, and quickly deployable housing solutions for students and young professionals.
