Reducing Malaria in Homes with Improved Air Cavity Ventilation

For some, a mosquito bite may simply be an itchy nuisance. However, mosquitoes are also carriers of infectious diseases, specifically malaria, which is highly prevalent in Kenya. Transmission of vector-borne diseases most frequently occurs within and around the home. Therefore, Habitat for Humanity is seeking solutions to significantly reduce the number of mosquitoes inside the home, thus reducing mosquito bites and consequently lowering malaria transmission.  The solution should also have a positive impact on the comfort of residents inside the home.

The proposal requires written documentation and a video of the proof-of-concept demonstration data.

Malaria-transmitting mosquitoes are adapted to enter and feed indoors, sustaining disease transmission despite decades of use of insecticide treated nets (ITNs). Rising temperatures, driven by climate change, are expanding the geographic area where malaria-transmitting mosquitos can thrive, impacting living conditions for many families. Higher indoor air temperature has been linked to increased exposure to malaria transmission due to reduced use of ITNs which are known to increase discomfort in hot environments (Kenya Malaria Indicator Survey 2020). To mitigate the consequences of global warming, it is important to maintain comfortable and healthy indoor temperatures within recommended thermal comfort zones. Where mechanical solutions like air conditioning and fans are either unavailable or insufficient, indoor air temperatures can be managed through design elements such as size and placement of doors, windows, and eaves. However, this should be done in a way that also keeps out mosquitoes and other disease-causing vectors. The main objective of this activity is to develop a cost-effective, viable, and acceptable solution for enhancing ventilation and keeping out mosquitoes as an improved version of the ‘air cavities’ solution from the Habitat for Humanity Challenge launched in 2021.

Images of the air cavities are shown below. They are inexpensive to make and can be installed in existing houses with little effort. The location and layout of the air cavities can be adjusted for optimal ventilation as well as aesthetic design. To promote adoption of the solution, residents must not only understand the utility of the air cavities, but they also have an incentive to change their existing homes. Therefore, Habitat for Humanity seeks the input of engineers, architects, interior designers, and others who can build a functional prototype that will also have curb appeal.  

The submission to the Challenge should include the following:

1. A detailed description of the proposed Solution and how it addresses each Technical Requirement presented in the Guidelines. This description should be accompanied by a well-substantiated rationale for the design, annotated drawings, and cost estimates.
2. Proof-of-concept demonstration data showing implementation of the proposed solution in a video (narrated in English or with English subtitles). 

The Challenge award is contingent upon theoretical evaluation and field validation of the submitted Solutions by Habitat for Humanity.

To receive an award, the Solvers will not have to transfer their exclusive Intellectual Property (IP) rights to Habitat for Humanity. Instead, Solvers will grant Habitat for Humanity a non-exclusive license to practice their solutions and the right to share awarded solutions with other nonprofit and for-profit organizations worldwide. Habitat for Humanity will make awarded solutions freely available to other nonprofit and for-profit organizations to help improve the state of low-income housing worldwide.

Submissions to this Challenge must be received by 11:59 PM (US Eastern Time) on TBD. 

Late submissions will not be considered.

ABOUT US

Habitat for Humanity International (HFHI)

Driven by the vision that everyone needs a decent place to live, Habitat for Humanity began in 1976 as a grassroots effort on a community farm in the United States and has since grown into a leading global nonprofit working across more than 70 countries.

An estimated 2.8 billion people live in inadequate shelter globally – a crisis that has been exacerbated by a lack of attention to, and investment in, informal housing markets. There is tremendous untapped potential within both the demand and supply sides of housing market that, if addressed, could substantially improve housing availability and quality for low-income households. The Terwilliger Center for Innovation in Shelter, a unit of Habitat for Humanity International, works within housing markets to expand low-income families’ access to new and resilient housing products, services and financing. Since 2016, Habitat’s Terwilliger Center has supported more than 45.2 million people’s housing journeys and helped catalyze over 12.1 billion USD for affordable housing solutions. Through shelter, we empower. To learn more, visit Habitat.org/TCIS.

Habitat is supported in this project by SeaFreight Labs (www.seafreightlabs.com), an open-innovation consultancy using global challenges to cost-effectively deliver breakthrough innovation. Participation in this project is a direct result of the recent SeaFreight Labs decision to join the Pledge 1% movement.

BACKGROUND

In 2021, Habitat for Humanity launched a global design challenge titled “Malaria Prevention through Innovations in Home Design or Home Life” or simply “the Habitat for Humanity Challenge.” The design challenge attracted 78 submissions as it solicited crowdsourced solutions to retrofit houses in malaria endemic regions of Kenya (western and coastal) to reduce the number of mosquitos entering the house. A key requirement of the challenge was that the solution could not cost more than 200 USD for a 36 square meter house with three rooms.

The most promising solution, “air cavities”, was selected after testing it in a semi-field structure within the Kenya Medical Research Institute (KEMRI). The solution entailed screening all openings (doors, eaves, and windows). For windows, the Solver proposed using screened air cavities made from PVC pipes and screening materials as a low-cost alternative to windows, especially for homes without windows. The solution demonstrated a substantial effect in deterring mosquito entry into the house, resulting in an impressive 89% reduction in mosquito numbers inside the house compared to unmodified houses.

1: A typical low-income house in Kenya               2: A typical low-income house in Kenya

3: A typical low-income house in Kenya             4: Mud-walled plastered house in Kenya

5: Modified hut with screened air cavities                        6: Closeup of screened air cavities

7: Air cavities – front side of house with no windows

8: Air cavities – detailed design

After the award, the solution was slated to be tested in an actual field trial by KEMRI in collaboration with HFHI in a community in western Kenya. This involved modifying existing houses to measure the efficacy in terms of mosquito control and indoor temperatures. Initial community engagement revealed that the residents had concerns about the application of air cavities in their homes. Reasons for the reservations are distilled below:

1. Privacy – The community indicated that air cavities as they had been designed by the Solver would deny them privacy as people outside could see inside the house through the cavities; especially at night when lights were on;
2. Cold – The community was concerned that the air cavities would also let in cold during winter months, since they could not be closed;
3. Security - The community raised concerns with the screening inside the pipes indicating that it could easily be pierced through by anyone with ill motives and/or even pets (cats) and pests (rats);
4. Lack of closing and opening mechanism – Households preferred openable windows over air cavities since they are used to openable windows;
5. Quality - The solution proposed creating windows with air cavities made from PVC pipes. Plastic is associated with poor/low quality materials. This perception was unfortunately ascribed to the solution.

Many houses have no openings besides a door and the primary reason for the lack of windows is the high cost of installation. Air cavities are an affordable solution, providing ventilation and light, and, if screened, will prevent the entry of mosquitos into the home. Compared to a standard window, the air cavities were considered an eyesore by pilot participants and the initial pilot was abandoned when homeowners were given a choice between the two. 

Habitat for Humanity is committed to optimizing the air cavities and making them an attractive yet functional feature of a Kenyan home. Solvers are encouraged to explore color, placement, shape, size, and additional features to enhance the decorative aspect of air cavities. It is important to highlight that cost is a significant factor in determining whether a viable solution can and will be adopted by the local community.

THE CHALLENGE

Habitat for Humanity desires a solution to dramatically reduce the number of mosquito bites for a typical family. The primary focus is to refine the air cavity design as a viable alternative to conventional windows while still preventing mosquito entry. Solutions should do nothing to increase the indoor temperature of the home or create discomfort for any resident. Alternatives to the air cavity solution will be considered if the Technical Requirements can be satisfied and comparable efficacy is demonstrated.

Habitat for Humanity is primarily interested in solutions that meet the following Technical Requirements. 

Must have:

1. Design/Solution is compatible with a low-income house for a typical Kenyan family
   • Utilizes locally available materials/solutions and/or materials that can be supplied by local vendors or improved from existing materials
   • Maintains cultural sensitivity and borrows from current/traditional housing forms and practices generally acceptable among Kenyans
   • Allows for expression of creativity by households when improving their homes
   • Retrofitting of an existing house to add air cavities with total cost not exceeding 60 USD for a 25 square meter house with two rooms (sitting room and one bedroom) 
   • Maximum combined area of two square meters – each air cavity configuration is expected to fall within the size range of 0.5 to 1.0 square meter
2. Maintenance-free and highly durable with a life span of 10+ years
3. Low tech and easy to install by fundis (local Kenyan laborers with limited construction experience); should not take more than a week to retrofit a house using the solution (for construction/architectural solutions)
4. Adaptable to a typical low-income Kenyan home as pictured above
5. Conforms to the Kenyan building code (for construction/architectural solutions)

Nice to have:

1. Addresses inclusivity and social impact
2. Sustainable; uses locally sourced materials
3. Is aesthetically pleasing and gives people the power to express themselves through art

DELIVERABLES

There are a few questions you must answer on the HeroX submission page, as well as submitting a video to show us your idea in practice and a PDF to explain all the details of your idea.

The PDF detailed submission should include the following:

1. Detailed description of the design solution and rationale as to how the proposed Solution addresses each Technical Requirement. This should include the design philosophy for ensuring privacy and security, as well as material specifications, instructions for installation, and predicted overall performance, with an emphasis upon temperature regulation.
2. Detailed drawings including, but not limited to the following:
   1. Well annotated sketches, plans, elevations, and sections if and where necessary 
   2. Shop drawings for the different elements of the proposed window design 
3. 3D models of the proposed solution and how it fits on existing houses
4. Cost estimate for the proposed design containing a breakdown of the following in a spreadsheet: 
   1. Material specifications for all components to be used
   2. Material quantities and their respective costs
5. Proof-of-concept demonstration in a video (narrated in English or with English subtitles) showing implementation of the proposed solution as well as demonstrating its ability to meet the Technical Requirements as outlined above.
6. Additional responses to any of the Challenge questions that did not fit in the character limits available.

Habitat for Humanity may wish to partner with the Solver at the conclusion of the Challenge. Solver should describe their expertise and include a statement indicating their interest in this opportunity.

Common Materials and Labour prices

SM: square meter; LM: linear meter; Pcs: pieces

GUIDELINES FOR THIS CHALLENGE

1. ELIGIBILITY

Employees and interns of Habitat for Humanity International (HFHI), as well as their immediate family members (spouse, parent, child, sibling, and their respective spouses) or persons living in the same household, whether related or not, are eligible to enter the Challenge; provided that they will not be eligible to receive an award if their Solution is chosen.  In addition, the Solutions of employees and interns of HFHI will fall under HFHI’s employment policies and be considered work product of HFHI. Please note, employees and interns of Habitat for Humanity Affiliates and independent National Organizations are eligible to enter and receive an award if their Solution is chosen.

2. EVALUATION CRITERIA

A maximum of three solutions will be selected by judges from HFHI and industry players for prototype construction. These solutions will be called "Finalists".  The following criteria shall be used:

1. Efficacy in preventing mosquito entry;
2. Impact on indoor air quality and ventilation;
3. Cost effectiveness;
4. Simplicity in design and installation;
5. Community perception and acceptance.

3. INCENTIVE PRIZE STRATEGY

Each selected solution (Finalist) will be replicated in 5 houses leading to a total of 15 houses. Subsequently, the modified houses will undergo comprehensive evaluation, with each solution assessed based on predefined criteria. The community’s feedback will be incorporated into the scoring to determine the best solution. This will also help in practically determining how easy it is to install the solution and capture actual costs.

The Challenge award is contingent upon theoretical evaluation and field validation of the submitted Solutions by Habitat for Humanity. Solutions selected for field testing will be awarded 3,000 USD. The winning solution that meets all the Technical Requirements will be rewarded with an additional 15,000 USD.

4. INTELLECTUAL PROPERTY

To receive an award, the Solvers will not have to transfer their exclusive Intellectual Property (IP) rights to Habitat for Humanity. Instead, Solvers will grant Habitat for Humanity a non-exclusive license to practice their solutions and the right to share awarded solutions with other nonprofit and for-profit organizations worldwide. Habitat for Humanity will make awarded solutions freely available to other nonprofit and for-profit organizations to help improve the state of low-income housing worldwide.