Drought-Resilient Reflective House Coating
Droughts currently directly affect 55 million people in rural Africa and cause billions of dollars of damage to houses. These events account for only 8 percent of natural disasters globally but pose the greatest natural hazard in Africa, accounting for 25 percent of all-natural disasters on the continent occurring between 1960 and 2006.
In Kenya, droughts are most prevalent - and the most willingness to pay for climate-resilient housing there since the government takes a special interest in developing good housing. Droughts are a difficult problem to solve because they have been variable and unpredictable, especially in the last 5 years.
In regards to the effects of droughts on housing, when you go long periods of time without rain, the water within clay and mud (since the majority of houses in rural areas are made up of mud) begin to evaporate and shrink. This forms cavities or gaps between the ground and the foundation. The foundation can crack as gravity pushes the weight of the house down into the gaps.
Going deeper into this problem, we found that, due to the scorching temperatures in Kenya, a high thermal mass provides comfort to residents. When the temperature is hot, the thermal mass of the material determines how long it takes for the heat that is absorbed in the material to get into the house. Ideally, when the heat is absorbed by walls and floors during the day, it radiates into the house during the nighttime when it tends to be colder. By the next morning, the home is cooler and the temperature is stabilized. For instance, glass has a short thermal mass, but the grass has a high thermal mass.
A paper based on surveys done in Kenya has shown that residents think “it is very uncomfortable to stay in [their] houses that are made of metal sheet” and “Houses are made of metal sheet that doesn’t keep the heat”. The status quo, where 82% of roofs and 8% of walls are made from iron sheets, isn’t convenient for many people because iron gets hot fast, leading to a low thermal mass (despite being robust so less maintenance is required).
We came to the conclusion that with drought-like weather, a potential alternative should have a higher thermal mass like grass but also be robust and require less maintenance, like iron sheets.
Our solution is a reflective coating solution made up of lime-based whitewash with added reflective materials and actively based off white roofs which are currently used in the developed world. This eco-friendly, low-cost method combines traditional techniques with modern technology to help keep homes cooler during droughts and hot weather conditions.
The key ingredients of this reflective coating solution include hydrated lime, water, local binding agents, fine-grained sand, and reflective materials such as crushed recycled glass or mica. When researching why the houses in Kenya are built the way they are with specific materials, we realize that communities depend on local sources, so it is feasible to build homes. Thus, we modified typical reflective coating solutions used in other areas to make it cheaper and locally-sourced. Here is a step-by-step breakdown of the process:
Hydrated lime (calcium hydroxide) is combined with water to create a lime-based whitewash, which has been used in Kenya for centuries. This traditional material is low-cost, environmentally friendly, and has good reflective properties due to its white color.
Local binding agents, such as casein or tannin-rich plant extracts from Acacia trees, are added to the whitewash mixture to improve adhesion and durability. Casein, a protein found in milk, and tannin-rich extracts both serve as effective binders.
Fine-grained sand is incorporated into the mixture at a ratio of 1 part sand to 4 parts whitewash. This step provides additional durability and abrasion resistance to the coating.
Reflective materials, like crushed recycled glass or locally available mica, are added to the mixture to enhance its reflective properties. The ideal ratio of reflective materials to the whitewash mixture is around 1:4. These materials act as reflective particles that increase the coating's ability to reflect solar radiation.
The ideal thickness of the reflective coating is 1-2 millimeters, ensuring optimal performance and longevity.
This innovative reflective coating solution has the potential to transform rural housing in Kenya, providing numerous benefits for residents and the environment alike:
Improved indoor comfort: By reflecting solar radiation away from the house and reducing heat gain, the coating helps keep homes cooler during droughts and hot weather conditions, leading to a more comfortable living environment.
Environmentally friendly: The reflective coating solution is made from locally sourced, eco-friendly materials, minimizing its environmental impact.
Adaptable to local conditions: The flexibility of this solution allows for the use of different binding agents and reflective materials based on local availability, ensuring that the reflective coating can be tailored to specific regions and resources.
It serves back to the millions of people in rural Kenya and saves billions of dollars of damage to houses. The people who find thermal discomfort in their homes and are affected because of the deteriorating structure stability and durability of the house, would find this solution valuable. As we scale up to other countries in the future, the impact will be tremendous.
This solution would provide a 5x increase in drought resilience, which is measured by the thermal mass of the iron vs our solution (https://thearchproject.substack.com/p/a-quantitative-analysis). A 1 mm coat of this solution protects a house from droughts and cracking in Kenya for 2-5 years and reduces risk of cracking by 75% by lowering the room temperature. We also calculated that the cost of this solution would be KES 8,397.50 (equivalent to 61.91 USD). To justify the economic investment made in this solution, we calculated our ROI. For every dollar invested in applying this solution to houses in Kenya, approximately $18.12 of value is created through energy savings and improved structural stability (check out our calculations in our Substack post: https://thearchproject.substack.com/p/economics-and-roi-on-reflective-coating)
Anya - I personally worked on AI and climate projects for the past few years. First, working with Open Climate Fix, I contributed to a solar mapping project and a project to graph global weather. I started working with a Harvard PhD at Solar4Africa to optimize battery chemistry based on one of my projects to accelerate the discovery of cost effective and efficient catalysts. Working with Solar4Africa, I was mentored by brilliant people who are experienced in deploying tens of successful pilots. With them, I started writing a whitepaper on the distribution of high quality products as a key barrier to people escaping poverty traps. What I realized from working with the company on selling and subsidizing energy related solutions was that when people had a fundamental asset (like their house) in jeopardy, they were much less likely to make rational decisions around the purchase of higher quality products. Consistently, I found that people living near coastal, disaster prone regions were significantly less likely to make investments in electricity when compared to someone with the same income in a different region. The second order consequences of this problem were immediately obvious - and this unobvious insight pushed me to work on this problem. I’m also currently pursuing an engineering undergraduate degree. I’ve always been drawn to hard technical problems and I see the vision of this project going further than a localized solution like simple coating.
Shiza - I’ve worked in the AI space for the past few years as well, specifically with vision models in the healthcare space. I have also worked on some climate projects in AI, such as classification models for marine life to solve the nutrient pollution problem that leads to a decline in marine population. I also came up with an idea called HelioRL that uses reinforcement learning (RL) to optimize the positions and orientation of dual-axis solar panels to maximize their energy production. I’ve always been fascinated by technical problems and I wanted to tie this into the climate resilient housing space, knowing that millions of people are left homeless because their houses break down in disaster prone regions. This summer, I’m going on a trip to Kenya supported by Global Encounters to understand the status quo of building houses. I will be piloting our solution in a local village for ~100 homes. I plan to collect data to track our impact goals and receive on the ground validation.
- Support informal communities in upgrading to more resilient housing, including financing, design, and low-carbon materials or energy sources.
- United States
- Prototype: A venture or organization building and testing its product, service, or business model, but which is not yet serving anyone
With $200, we were able to build a prototype of the house by sourcing materials that would be used in a developing region in Kenya. Experimenting with different solutions (including commercially available ones in the US and Canada), we found the optimal ingredients for a whitewash that had the ability to protect the house from cracking at more than 120 degrees fahrenheit for more than a week which we equated to be more than the extreme end of temperature in Kenya. We experimented with a variety of different ratios and tried to optimize the cost of this solution when locally sourced. The solution we have now gives us an ROI of roughly $18 for every dollar invested. Talking to government officials, Non profits, and NGOs, we’re still continuing to prototype but require funds to attain more materials. We plan to test in a commercial heating facility with a bigger structure with the goal of further optimizing the materials and cost to get to roughly $50 of value created for every dollar invested. While we started with a $500 grant, we need funds to bring down the cost of the solution (which, if proven to provide a direct ROI, becomes much more appealing as a subsidized investment for the government). Ideally, we would both like to conduct on the ground testing to see if a better solution could address multiple housing problems, but for now we’re aiming to improve the solution and get locally sourced materials for cheap transported to fairly rural places in Kenya.
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My primary motivation for applying to Solve is the network and community experience of people passionate about the same problems. I think solutions implemented in the developing world, while having a large upside, come with a big risk. Being part of this community is like having the experiences of everyone to learn to pilot and eventually scale my housing solution.
If given the opportunity to join the Solve community, I will be amazed at the quality of entrepreneurs and changemakers gathered in one room.
While a simple idea, I believe this solution represents what MIT and MIT Solve represents - scaling up impact by creating customized, thoughtful solutions designed to improve the lives of thousands of people. I’m driven to work on housing because of its second order impacts on reducing poverty in the world. Personally knowing entrepreneurs and solutions that Solve supports, I resonate with the culture of improvement, pivoting, and first principles thinking Solve innovators all possess. Regardless of whether this specific pilot project ends up succeeding or not, I’m driven to work on the housing problem in a way that makes a measurable impact on its second order effects of limiting poverty reducing investments. I see Solve as the best community to be a part of to critically take steps to reanalyze our idea and execution
I know that MIT’s network and contacts will open doors to avenues that we would otherwise have not been able to access- helping us create partnerships to scale our impact. I’m excited to go through the rigorous due-diligence process and have our solution reviewed in microscopic detail by such a renowned institution to validate the impact of what we’ve worked on for the past few years. To me, MIT Solve is a community that holds solutions and impact to high standards that I aspire to be a part of to also learn and get the resources to scale my impact.
- Business Model (e.g. product-market fit, strategy & development)
- Financial (e.g. accounting practices, pitching to investors)
- Product / Service Distribution (e.g. delivery, logistics, expanding client base)
What makes this solution innovative over current housing solutions is the approach to implementation and engineering. Most housing solutions plan to scale too quickly and don’t focus their initial research and product creation on a hyper localized solution as I believe they should. Designing a solution around the specific climate problems facing houses in a developing region ensures that it solves a problem and creates valuable data points for quickly scaling localized solutions to other regions. This approach to designing a product pipeline around the conditions of a specific region means that while progress in the beginning is likely to be slow, it’s bound to be effective because of the thought and intentionality of the actual design. I believe the valuable data we’ll collect will help catalyze other innovations in the space and more broadly, in different regions as we’ll be able to apply our learnings between different projects and make each one after more effective, efficient, and impact oriented.
We’ve set impact goals for the next year and the next five years, focusing on promoting climate-resilient housing and sustainable living in developing countries.
First-year goals:
Implementation of the Reflective Coating Solution in Kenya: Our primary goal in the first year is to introduce the lime-based whitewash reflective coating solution to at least 500 households in Kenya. We’ll work closely with local communities, providing education on the benefits of this solution, as well as organizing workshops and training sessions to teach residents how to apply the coating themselves. Once we reach a high enough ROI, we’ll be able to collaborate with local governments and NGOs to secure funding and support for this initiative.
Monitoring and Evaluation: To ensure the effectiveness of our reflective coating solution, we’ll closely monitor and evaluate its impact on indoor comfort, energy consumption, and overall quality of life. Using this data, we’ll refine our solution and improve our prototype
Five-year goals:
Expansion of Climate-Resilient Housing Solutions: Over the next five years, we aim to implement our climate-resilient housing solutions in more developing countries starting with Nigeria, Bangladesh, India and Nepal, impacting over 20,000 households. We’ll collaborate with research institutions and international organizations to identify region-specific solutions that can be adapted to local needs and resources.
While researching for Kenya, we thought of economically incentivized solutions based on the root causes of housing rebuilds being so frequent in the developing world that we’d have queued in addition to the Kenya project with the goal of increasing our surface area of impact and gaining more insight and experience in the space while making a positive impact as soon as we feasibly can.
Beyond Five-Year Goals: Factory-Produced Low-Cost Climate-Resilient Housing
Design and Development: We envision a future where affordable and sustainable housing is accessible to everyone. To achieve this, we’re working (very early stages) on the design and development of factory-produced low-cost climate-resilient housing units. By leveraging advancements in construction technology, materials science, and manufacturing processes, we want to work on creating modular, scalable housing solutions that can be easily assembled on-site and customized to fit various environmental conditions and cultural preferences.
- 1. No Poverty
- 3. Good Health and Well-being
- 9. Industry, Innovation, and Infrastructure
- 11. Sustainable Cities and Communities
- 13. Climate Action
- 15. Life on Land
Since we’re still in prototyping stage, our main benchmark for impact goal is getting to $50 of value created for every dollar invested. After then, when we’re piloting our solutions, we’ll monitor our progress using the following techniques:
Baseline Data Collection: Before implementing our housing solutions, we plan to collect baseline data related to energy consumption, indoor comfort, and housing quality. This data serves as a reference point to evaluate the impact of our interventions.
Key Performance Indicators (KPIs): We’ve established a set of KPIs that align with our impact goals. These KPIs include the number of households reached, the adoption rate of sustainable housing solutions, and the reduction in energy consumption over the short term and the reduction of cracking in the long term. By regularly monitoring our progress against these KPIs, we can make data-driven decisions to optimize our efforts.
Post-Intervention Monitoring: After implementing our housing solutions, we hope to work with partners to continuously collect data on energy usage, indoor temperature, and overall housing quality. This information will help us assess the effectiveness of our interventions and make necessary adjustments to improve their impact.
Beneficiary Feedback: After implementation, direct feedback will help to gain insights into the strengths and weaknesses of our interventions, as well as identify any unanticipated consequences.
External Evaluations: To ensure an unbiased assessment of our progress, we collaborate with external evaluators, such as research institutions or third-party auditors, to conduct independent evaluations of our projects. These evaluations provide an impartial perspective on our impact and help identify areas for improvement.
Periodic Reporting: We’ll create comprehensive progress reports at regular intervals, which include updates on our KPIs, insights from beneficiary feedback, and findings from external evaluations to create transparency with stakeholders and also keep an open line for their potential help in the future.
Describe in simple terms how and why you expect your solution to have an impact on the problem. This is called a theory of change or logical framework, and it should link your activities to immediate outputs and longer-term outcomes for your target population. In addition to illustrating logical links between activities, outputs, and outcomes, a strong theory of change provides evidence to support the existence and strength of those links, such as third-party research, findings from a process or impact evaluation, data from interviews with your target population, etc. If you’re unsure how to answer this, start by following these guidelines or watching this intro video, or enroll in our online course.
In the short term, houses will be 5x more climate resilient (our quantitative analyses: https://thearchproject.substack.com/p/a-quantitative-analysis and https://thearchproject.substack.com/p/economics-and-roi-on-reflective-coating), in terms of the thermal mass. This would decrease the risk of cracking by 75% and increase the stability and durability of rural housing in kenya. Another short term outcomes is also improved comfort when conducting surveys and reading papers about housing in rural Kenya and how it impacts the residents there, we realized that they found the low thermal mass or iron sheets uncomfortable because their house wasn’t able to cool properly (https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-15281-y - “When it is sunny it is very uncomfortable to stay in our houses that are made of metal sheet…Houses are made of metal sheet that doesn’t keep the heat.”). Also, with greater thermal mass, houses would require less energy to heat and cool, as the house would be better at retaining heat during cold weather and keeping cool during hot weather. This would lead to lower energy bills for residents and a reduced environmental impact.
This means that in the long term, some of the outcomes would be:
Reduced poverty: with stronger and more durable homes that can help prevent damage and destruction during natural disasters, people's assets can be protected and it can reduce the economic burden of rebuilding. On top of this, people would be even more likely to make investments into energy and other commodities that can take them out of the poverty cycle
Reduced migration: More resilient homes could reduce the need for people to migrate to urban areas in search of better housing and job opportunities, thereby reducing urban overcrowding and its associated problems.
Reduced greenhouse gas emissions: By improving the thermal mass of homes, people may be less reliant on energy-intensive heating and cooling systems, reducing greenhouse gas emissions and contributing to efforts to mitigate climate change.
The core technology of our solution lies in the innovative reflective coating made from a lime-based whitewash and added reflective materials, which significantly improves the thermal mass of housing materials, making homes more climate-resilient and comfortable for residents in drought-prone areas of rural Kenya. This technology combines traditional techniques and locally sourced materials with modern advancements in materials science and manufacturing processes.
In the next five years, we aim to expand the impact of our core technology and its applications in promoting climate-resilient housing and sustainable living in other developing countries. We will continue to improve the reflective coating solution by exploring alternative binders, reflective materials, and manufacturing techniques. This will ensure that our technology remains adaptable to local conditions and resources while maximizing its efficiency and effectiveness.
As we introduce our solution to more regions, we will work on streamlining the manufacturing process to make it more cost-effective and accessible. This may involve partnering with local manufacturers and suppliers to optimize production, distribution, and application of the reflective coating.
We will start implementing our climate-resilient housing solutions in countries such as Nigeria, Bangladesh, India, and Nepal, impacting over 20,000 households. Collaborations with research institutions and international organizations will help us identify region-specific solutions that can be adapted to local needs and resources.
In the long-term, we envision designing and developing factory-produced, low-cost climate-resilient housing units. By leveraging advancements in construction technology, materials science, and manufacturing processes, we aim to create modular, scalable housing solutions that can be easily assembled on-site and customized to fit various environmental conditions and cultural preferences.
By focusing on the continuous improvement and expansion of our core technology, we hope to make a significant impact on promoting climate-resilient housing and sustainable living worldwide. By enhancing the thermal mass of housing materials, our technology can directly contribute to poverty reduction by helping people in disaster-prone regions secure their homes and make long-term investments in their future.
- A new application of an existing technology
- Manufacturing Technology
- Materials Science
- Kenya
- Philippines
- Not registered as any organization
Being born in developing countries (India and Pakistan), Anya and I have witnessed the problem with climate resilient housing and with some of our personal experiences, we are motivated to solve this problem for the hundreds of millions of people around the globe who don’t have access to stable and durable housing.
To make our solution more inclusive, we are already using materials that are locally available and affordable to reduce the cost of the solution and make it accessible to low-income households in rural Kenya. We want to ensure that it can be easily produced, applied, and maintained by the local community, without requiring specialized skills or expensive equipment. None of the components of our solution require any type of importing nor delivery since they can be easily found in rural areas of Kenya. This can also create opportunities for local employment and support the local economy.
We also want local NGOs, government agencies, and other stakeholders to leverage resources and expertise, especially for potential subsidies. This will help to ensure the project's long-term sustainability and reach a wider audience.
Going on ground, we also plan to engage with local communities and stakeholders to gain a better understanding of their needs and priorities. This will help ensure that the solution is relevant and responsive to the needs of the community.
When deploying the solution, we want to also provide training and educational resources to the community on the benefits of the reflective coating, its application, and maintenance. This can emphasize the importance of climate resilience and how it can improve their living conditions, making them more likely to invest in poverty-reducing commodities. To further involve the community, we want to be intentional about establishing clear and transparent communication channels with them and other stakeholders. We have gotten advice from many researchers that it helps to keep the customer updated on information about the project's goals, progress, and outcomes, and encourage feedback and dialogue to foster trust and collaboration.
Your business model describes how you provide value to the populations you serve, both in terms of impact and revenue. Think about your key customers and beneficiaries. What products or services do you provide them? How do you provide these products or services? Why do they want or need them? If you’re unsure how to answer this, start by completing the Social Business Model Canvas or enroll in our online course.
Using a social enterprise model, these would be our components after developing the full prototype and ensuring that the product is easy to apply, effective, durable, and requires minimal maintenance:
Local Production: we would set up a production facility within the community or nearby region to manufacture the reflective coating. Furthermore, we would employ and train community members in the production process, creating local jobs and fostering skill development (as we scale up)
Pricing Strategy: Implement a tiered pricing strategy that takes into account the income levels of the target households. Offer a subsidized rate for low-income families, a standard rate for middle-income families, and a premium rate for wealthier clients who want to support the social mission. This would also ensure that people in different areas with various price sensitivities can pay as much as they can.
Financing Options: Collaborate with microfinance institutions or community-based organizations to offer affordable financing options for households to purchase and apply the reflective coating. This can include microloans, installment plans, or revolving funds. We are planning to collaborate with the government as well since the Kenyan government has placed housing high on their priority list (from the research and papers we have read)- this would also help with subsidies. We would like to also partner with NGOs and international organizations focused on climate resilience and housing solutions. Leverage their expertise, resources, and networks to improve and scale the project.
Obviously, this is not a finalized strategy, but through monitoring and measuring impact, we would be able to collect data on energy savings, indoor comfort, and the overall impact on the community. And as we scale to different regions other than rural Kenya, the business model would get complicated because environmental conditions, government collaborating, and other factors aren’t the same.
- Government (B2G)
Our plan for financial sustainability involves purchase orders from governments / housing contractors (in some countries). To have these orders initiated, we need to have a proven model of financial return. During idea phases, after being able to communicate our proposed impact we made our research and testing sustainable through grants.
We’ve raised grants (~2k) that have helped us with initial prototyping but unfortunately, aren’t enough for on ground testing and validation.
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Co Founder ARCH project