Malaria Prevention Housing
PlasticWrap: Creating Identity in the Minkoaméyos Community
The core of the problem is not the Malaria – we cannot completely remove the disease through planning or technology solutions as they exist today – the problem rests in the current behavior and habits of the community members. Change their behavior…and we begin to create real impact against the spread of Malaria.
That being said - planning, technology and design can help to reduce the transmission of Malaria from mosquitoes. The existing buildings are permeable, which allow the airborne insects to enter and exit freely. This mosquito species in particular flies upward when its confronts a wall, so the unsealed eaves of the buildings are of particular concern. The challenge, from a design perspective, is that there are a variety of building types in the city and labor is particularly unskilled. The buildings vary both in shape and size as well as in construction material. Each building is also unique in terms of damage and weakness to mosquito penetration. Behaviorally, the local population does not like to sleep under the mosquito nets, while the solution never fully seals the space.
A secondary problem is the uncontrolled waste streams. There is a waste pickup system that runs along the main road but is not expanding to keep up with the growing population. Behaviorally, there is no understanding of or urgency to “recycle” or “reuse”. The community simply does not see a benefit yet. This behavior is a reflection of the population needing a sense of pride and responsibility for their own neighborhoods, which is a major challenge. The population is growing, they are now a recognized neighborhood of the capital city, and they need to change their behavior. This built environment is a potential canvas for individuals to take ownership of their community and collectively make a change
The conceptual goals of PlasticWrap are simple: 1) to reduce the transmission of Malaria by controlling indoor mosquito density; 2) to reduce the volume of trash (mainly plastic, metals and glass) disposed of by the village; 3) to develop a sense of identity for occupants and instill a sense of place for their community; 4) to extend cultural stories into the building fabric – facilitating a core behavior change; and 5) to introduce solutions that are not only built by local people with local materials, but can also be maintained and repaired locally with little/no new skills.
The Conceptual Solution
PlasticWrap reduces Malaria transmission by extending the current structural grid of each home and creating a double skin façade around the building envelope. This not only seals the building from mosquitoes, but introduces an opportunity for ownership and responsibility through the reuse of plastic waste to act as fill for the color pattern facades of the community.
The design reduces the permeability of the building envelope and eliminates the vector control areas by wrapping the façade in a system of modular bamboo and net tiles. The result is a controlled environment throughout the entire living space of each home. Inhabitants no longer need to sleep under mosquito nets or worry about mosquitoes thriving inside their homes.
The solution utilizes local materials and simple construction techniques to ensure local participation. It is also very modular and building type agnostic, so there is significant opportunity for assembly line production systems to be created within the local communities.
PlasticWrap reuses, and thus reduces, plastic waste by using colorful bottles and strengthening personal identity with locally understood patterns. The bamboo and net modules contain triangular pockets that can be filled with different colors of finely cut strips from recycled and color sorted plastic. The patterning created from these pockets reflects the local culture’s specific use of patterns in basket weaving. The result is the potential for unique color schemes and pattern identities for each each building, which would develop a sense of individuality and creativity for each building owner. This drives behavior change.
As a result, Public Health improves, Community identity increases and the population begins to see new value in traditional waste streams, opening their minds to new opportunities with other types of waste material.
Construction Materials and Methodology
Construction is intentionally simple and modular. The use of parametric software in the design process allows for simple construction instructions and diagrams. The required materials are all locally sourced and easy to work with. Since building types vary, the design solution is adaptable to each typology with little to no customization. Custom solutions by building type are unsustainable at this scale. The modularity of the design allows for rapid manufacturing and scaling as the solution is adopted throughout surrounding communities.
Materials include two types of local bamboo (small green and small yellow), mosquito nets, poto-poto, nails, string and plastic waste.
The first modular component is the triangular pockets and tiles. They are made of mosquito netting, and small yellow bamboo rods. The bamboo is filleted in half, netting is placed in-between the two fillets, poto-poto is used to fill the space and hold the netting in place, then a few nails are driven through the bamboo to secure it back together.
As the triangles are being assembled, the home owners can fill the pocketed modules with thinly cut plastic bottles to add texture and color to the façade. Assembling a series of triangles together creates the larger module that is attached to the exterior (small green) bamboo poles. These small green bamboo poles are the vertical supports running from the ground up to the roof eaves of the buildings. A foot deep trench is dug around the perimeter of the home. The ground end of the vertical supports are inserted into plastic bottles, filled with dirt, and buried in the trench as anchors. The roof end of the supports are attached by nailing two parallel bamboo rods to the frame of the roof creating a rail system. The roof ends of the vertical supports are inserted into this ‘rail’ and anchored with poto-poto. The ground level triangular module has extra netting that extends into the trench. It is buried along with plastic bottle anchors to create a sealed seam along the ground. The highest triangular module has extra netting that is attached to the underside of the roof by placing it in-between a bamboo rod or piece(s) of scrap wood and the roof frame.
Construction Time Per Home
The modularity of the design supports an assembly line fabrication process. This significantly speeds up the construction time. With a team of 10 people, our design could be built and installed on all 24 homes in less than 6 weeks. We imagine much more community support than just 10 people, so consequently, construction time is a minimal risk.
Focusing on solving the building envelope challenge will significantly reduce the transmission of Malaria from mosquitoes and increase the overall health of the population. When the building is wrapped in this façade there are two layers of protection, the outer net layer and the inner building wall. Furthermore, the entrance/exit ways utilize the idea of the vestibule, where there are two ‘gates’ a person must pass through to get in and out of the home. This solution reduces the likelihood of mosquitoes following people into homes through the doorways. Also, by wrapping the building, windows and doors can actually be left open, increasing natural airflow through the buildings and improving the quality of the indoor environment.
The bamboo/net modules are building type agnostic. There are three different sizes of triangular modules. Depending on the height of the wall section they will cover, the number of triangles stitched together will change. The material characteristics of bamboo allow it bend and not weaken, so the same module is flexible itself and does not require a degree of precision beyond the capability of the local labor force.
Beyond pure function, the solution encourages self expression and creativity. The triangular pockets in the modules allow each building owner to customize their solution by adding colorful plastic bottles to fill each pocket. Triangles were chosen to create a general pattern, similar to their traditional basket weaving. Each triangle has a potential volume of 0.05 cubic meters, so within a single home, there is a potential to re-use 8 cubic meters of plastic. Much like the Favela’s of Rio, the variety of colors and possible sub-patterns will give each building a sense of individuality, while still maintaining the high level pattern of the neighborhood. This allows community members to identify with their environment at both a single building level as well as a regional level. It introduces cultural and artistic expression into a traditionally very insipid feature. The goal is to bring identity and life to the community as a whole.
Durability is a key component of any solution. Our solution is so modular, that a small failure is easily repaired by an acute repair (like a patch) or by replacing the entire module. The double skin also provides a level of redundancy in protection. In order to increase the durability of the nets, we re-inforce them with a simple bamboo lattice and add additional rigidity through the plastic waste.
The solution scales easily. The modular design lends itself to assembly lines and rapid production. Furthermore, the materials, tools and skills required to assemble the components and install the modules are local, common and simple. The entire community can be part of this solution. It has the potential to create a micro-economic opportunity within any community. At a macro-level, there is more supply than demand in Cameroon for bamboo. This solution would significantly boost the demand for the material, creating a better market environment for the entire bamboo supply chain.