FAQs for Cool Roofs

What is a ‘cool roof’?

The term ‘cool roof’ refers to a roof that stays cool in the sun through the use of coatings or materials that maximise the amount of incident solar radiation that is reflected, and the amount of absorbed radiation that is emitted back into the atmosphere, and so minimising the radiation that is conducted to the building below as heat. The solar reflectance (SR) and thermal emittance (TE) of a cool roof product (coating or material) are each measured with a value between 0 and 1, and these two measures can be combined into a single measure called the ‘solar reflective index’ (SRI), which takes a value between 0 and 100. The higher the value, the cooler the roof. Many cool roof products are white but they can come in a range of different colours and materials.

What are the benefits of cool roofs?

The vast majority of roofs are dark in colour and absorb large amounts of solar radiation, transmitting it to the rooms below and to the air above as heat. The use of cool roofs can reduce indoor temperatures to improve thermal comfort, lower energy consumption for cooling in buildings and, if deployed at scale in a concentrated area, reduce the external ambient temperature of whole communities through decreasing the ‘urban heat island effect’. Reducing temperatures in buildings and communities with cool roofs promotes improved health outcomes, air quality, productivity, and other benefits that can equate to a monetary value up to 12 times the cost of installation and maintenance.

Studies have shown that in a building without air conditioning, replacing a dark roof with a white roof can cool the top floor of the building by 2 to 3 degrees Celsius and that the net annual energy use for a one-story building with air conditioning is reduced by up to 20 percent upon raising the solar reflectance of the roof from 10 to 20 percent to 60 percent.

The use of cool roofs can have additional benefits beyond the direct cooling effect on the building below and air above. They can increase the lifetime of the roof by reducing damage from solar radiation and in some cases improve water resistance of the roof. Installation of cool roofs can also provide economic benefits through skilled job creation and training.

FAQs for the Challenge

What is the Million Cool Roofs Challenge?

The Million Cool Roofs Challenge is a US$2 million initiative to encourage to rapid scale up the use of highly solar reflective, ‘cool’ roof products in countries in hot climates that face significant risks associated with a lack of access to cooling. A $1 million final prize will be awarded to the team that proves the most effective, sustainable and transferable model for scaling up cool roofs, and that has deployed 1 million square meters of cool roof coating/material between August 2019 (exact date TBC) and December 2020. Up to ten grants of $100,000 are available to support entrants in meeting the goal of the Challenge. Only selected participants that have applied to the Challenge by 20 May 2019 will be eligible for the final prize.

What problem is the Million Cool Roofs Challenge trying to solve?

A recent report published by Sustainable Energy for All and the Kigali Cooling Efficiency Programme, ‘Chilling Prospects: Providing Sustainable Cooling for All’, estimated that there are 1.1 billion people facing access to cooling risks. This includes 630 million slum dwellers living in hotter-climate urban areas where electricity services do not exist, are intermittent, or are too expensive. In addition, the report identified 2.3 billion people in developing countries who are increasingly able to purchase air conditioners, but can only access the most inefficient and thus energy-intensive models, associated with higher greenhouse gas emissions and usage costs.

Cool roofs have been shown to be a sustainable and cost-effective tool to address risks associated with lack of access to cooling. They have already seen widespread use in high income contexts and could have a significant impact if scaled up rapidly in lower income countries at risk of heat stress. However, while there has been some encouraging activity towards this, there is a lack of understanding of how to effectively drive widespread adoption of cool roofs in lower income countries. This is the problem that the Million Cool Roofs Challenge seeks to solve. Some of the key barriers that entrants to the Challenge will need to overcome include awareness, financing, understanding of effective policy and implementation frameworks, lack of local markets and the availability of local data.

The Challenge aims to address this problem by seeding activity in multiple countries where there is a significant need for greater access to cooling, providing an incentive to swift action and supporting capacity building and awareness raising. The Challenge seeks to increase the visibility of cool roofs as a solution and generate multiple case studies of effective approaches, and through this to embed the use of cool roofs globally as a sustainable and cost effective way to improve access to cooling where it is most needed.

What type of solution is the Challenge seeking?

The Challenge is asking entrants to develop and demonstrate approaches to rapidly scaling up the use of cool roofs, leading to the installation of 1 million square meters of cool roof product by December 2020 (exact date TBC). Entrants should also give an indication of a long term strategy beyond that date. The Challenge is open as to what proposals include, but they are expected to involve one or more of the following activities:

  • Demonstrator / pilot projects

  • Training programmes

  • Policy change (e.g. building codes, procurement policies)

  • Awareness raising and communication campaigns

  • Volunteer programmes

  • Financing and fundraising programmes

  • Stakeholder engagement and coordination

  • Building up of local supply chains

  • Data gathering and impact measurement

  • New business models for companies selling cool coatings

How is the Challenge structured?

The Challenge opens for applications on 28 January 2019 and applications must be submitted by 20 May 2019. In August 2019 teams will be informed if they are accepted onto the Challenge and the ten best proposals will each be given a $100,000 ‘Boost Award’ to support the scale up of cool roofs solutions. Only entrants that have applied by 20 May 2019 and been selected to compete will be eligible for the final prize. Competing teams will then have until December 2020 to develop and demonstrate their approach to scaling up cool roof products and to reach one million square meters of cool roof product deployed. The winner will be the entrant that the judges deem to have developed the most effective, sustainable and transferrable model for scaling up cool roofs. The judging criteria is detailed in the Implementers’ Handbook and on this page of the website.

How much funding is available?

The Challenge is offering up to ten ‘Boost Award’ grants of $100,000 to support teams in reaching the final goal, and a $1 million final prize to be awarded in March 2021 to the team that has demonstrated the most effective approach to scaling up cool roofs. Only entrants that have applied for Boost Awards by 20 May 2019 and subsequently been selected to participate will be eligible for the final prize.

What long-term outcomes is the Challenge aiming to achieve?

The Million Cool Roofs Challenge aims to achieve the following outcomes:

  • Outcome 1: Close the cooling access gap in critically affected countries. Reflective, “cool” roofs and walls are an essential first strategy to improving cooling access. These interventions reduce base and peak demand for cooling demand in mechanically conditioned buildings, improving thermal comfort for those inside. For the vast majority of buildings that will not be mechanically cooled, cool surfaces are one of the few strategies that can deliver meaningful cooling access by reducing mean indoor temperatures at a building scale and mean ambient air temperatures when deployed on a community- and city-wide scale. The use of quality, cost effective product and effective deployment through skilled workforce is a key to success.

  • Outcome 2: Send a clear signal to the market and policy developers that there is global demand for cool roof products. The competitive grant pool will be the largest ever to focus on cool roofs and thermal comfort and will build relationships in large, but previously untapped, markets. Visible and high profile deployments, ideally supported with performance data, will bring buy-in from market and governments.

  • Outcome 3: Create the conditions for sustainable, accelerated deployment of cool surfaces in countries with a large gap in access to cooling. The initiative will encourage the development of policies, programs, and markets to deliver over 1 million cool roofs across target countries and create jobs. In countries with high penetration of mechanical space cooling, the program will save hundreds of millions of dollars and avoid hundreds of thousands of tons of greenhouse gas and ozone precursor emissions.

Who is running the Million Cool Roofs Challenge?

The Challenge is being run by the Kigali Cooling Efficiency Programme in collaboration with the Global Cool Cities Alliance, Sustainable Energy for All and Nesta’s Challenge Prize Centre. More information about these organisations is available on the Partners page.

How is the Million Cool Roofs Challenge funded?

The Million Cool Roofs Challenge is funded as one part of the Kigali Cooling Efficiency Programme (K-CEP), a philanthropic initiative to support the Kigali Amendment to the Montreal Protocol. K-CEP is funded by 17 foundations and individuals, a full list of which is available on the K-CEP website.

Why are you running the Million Cool Roofs Challenge?

The recent paper by SEforAll and K-CEP, Chilling Prospects: Providing Sustainable Cooling For All, directly linked strategies to deploy more highly reflective “cool” roofs and walls with achieving the goals of the Paris Climate Accord, Sustainable Development Goals, and the Kigali Amendment to the Montreal Protocol. It highlighted that 1.1 billion people in hot climates face cooling access risks, and that a further 2.3 billion are at risk of purchasing an inefficient cooling device that could result in high greenhouse gas emissions.

Cool roofs offer proven benefits to people at risk of lack of access to cooling, particularly thermal comfort and associated health and productivity improvements. In buildings that have air conditioning, cool roofs can reduce energy consumption and thus cut costs and reduce greenhouse gas emissions. Developing cool roof products and programmes can also create new skilled job opportunities with associated economic benefits.

However, there are barriers to the adoption and scale of cool roofs that include awareness, lack of financing and limited understanding of the most appropriate policy frameworks and business and operation models. This programme seeks to overcome those barriers by encouraging widespread deployment of cool roofs and the development of new approaches to scale. This programme aims to seed future widespread use of cool roof solutions where it is most needed, ultimately leading to one million cool roofs and beyond!

What are the key dates of the Challenge?

  • 6 November 2018 - Announcement at the 30th Meeting of the Parties to the Montreal Protocol; online registration opens

  • 28 January 2019 - Application for Boost Awards opens, competitive awards of $100,000 to support the rapid deployment of cool roofs

  • 20 May 2019 - Deadline for applications for Boost Awards

  • August 2019 - Up to ten finalists selected and awarded $100,000 each

  • December 2020 - Deadline for finalists to achieve scale

  • March 2021 - Winner announced and awarded $1 million

Who can apply to the Challenge?

The Challenge is open to single organisations or consortia of multiple organisations, but applications must have a single Lead Applicant that is a registered legal entity, and deployment of the cool roof product must be in an Article 5 Group 1 developing country as defined in the Montreal Protocol. The Lead Applicant can be based anywhere in the world, but if they are not based in the country of deployment they must have a partner organisation that is. The Lead Applicant must be legally allowed to receive funding from UK and US-based institutions.

The Lead Applicant may be any kind of legal entity, but it is expected that the majority of participants will be local or national government organisations, local or international non-profit and non-government organisations, academic & research institutes, international organisations or private companies such as materials providers, construction and property firms or energy suppliers. Full details can be found in the eligibility criteria.

Can an organisation make more than one application to the Challenge / be part of multiple consortia?

Individuals organisations can make multiple applications to the Challenge and may be in more than one consortium.

Who will receive the funding?

The Lead Applicant will receive the funds and be responsible for any allocation or subcontracting with partner organisations.

Why are some countries not eligible as locations for deployment?

The Million Cool Roofs Challenge is funded by the Kigali Cooling Efficiency Program, which exists to support the goals of the Kigali Amendment to the Montreal Protocol. Signatories to this amendment committed to the phase down of HFCs, coolant gases that have a high global warming potential. The Montreal Protocol has special provision for developing countries under Article 5 of the agreement, referred to as ‘Article 5 Countries’. In the Kigali Amendment, some countries committed to a more rapid phase down of HFCs, and these are termed ‘Group 1’ countries. It is Article 5 Group 1 countries that are eligible for additional support through the Kigali Cooling Efficiency Program and thus also the Million Cool Roofs Challenge.

What type of cool roof materials can be used in the Challenge?

Any roofing material is eligible as long as it meets the following requirements.

  • Product solar reflectance and thermal emittance shall have been tested by a nationally recognized laboratory or equivalent. Authentic testing report or product label clearly stating the procedure used for testing shall be documented. KCEP may collect random sample of the product for testing to check performance.

  • Minimum Product Performance (Values for solar reflectance and Emissivity):

    • Solar reflectance (SR) equal to or greater than 0.70

    • Thermal emittance (TE) equal to or greater than 0.75

  • You can read more about the eligibility of products here.

How can applicants access appropriate cool roof materials?

Many countries have local suppliers that can provide appropriate cool roofs materials but there are also countries that currently do not have indigenous supply chains. Several companies have expressed interest in supporting applicants to this Challenge and prospective entrants who would like to know more about cool roofs and/or be put in contact with cool roof materials suppliers are encouraged to get in touch by emailing team@coolroofschallenge.org. In addition, technical guidance on cool roof materials and procedures for applying them can be found on the Apply page.

I work for a company that supplies cool roof products, how can I get involved in the Challenge?

Suppliers of cool roof products that wish to be connected with prospective applicants to the Million Cool Roofs Challenge are encouraged to get in touch with us directly at team@coolroofschallenge.org and we will endeavour to connect suppliers with potential partners.

FAQs for Applications & Boost Awards

What types of activities are eligible for funding through the boost awards?

The $100,000 Boost Award funding may be put towards any activity that helps to encourage the widespread deployment of cool roof materials, including development of policies, business models and operational frameworks. Items eligible for funding include materials costs, staff time/labour costs, training costs, evaluation and monitoring equipment, and communications materials. Projects may include cool roofs demonstrators, development of policy frameworks and updates to building codes, finance programmes, data gathering and cool roof evaluation, communication and dissemination around cool roofs or any other activity that accelerates cool roof deployment.

How do I submit an application?

Applications can be made via the Entry Form and must be submitted by 23:59 BST on 20 May 2019. If you’d like to preview the questions on the form before starting your application, you can do so on this page.

What language can I submit my application in?

All applications must be made in English.

When will applicants be notified of the outcome of their application?

Applications to the Challenge close at 23:59 BST 20 May 2019. Applicants can expect to be informed of the outcome of their application no later than 31 August 2019.

Is match funding essential for receiving a Boost Award?

Applicants are encouraged to provide additional resources, and resource commitment is one component of the judging criteria, however this is not mandatory. These resources may include additional funding or in-kind support such as materials, human resources/expertise, facilities and complementary programmes around sustainability and the built environment.

How will the applications be evaluated?

Applications will be evaluated by an expert international judging panel according to the judging criteria, available here.

If I am granted a Boost Award, who will I be contracting with?

The Boost Awards will be disbursed and managed by Nesta, in the UK. The $1 million final prize will be disbursed by ClimateWorks, a US-based foundation that holds the majority of the funds for the Kigali Cooling Efficiency Programme.

Is applying for and/or receiving a Boost Award a prerequisite to competing for the final prize?

Yes, only teams that have submitted an application by 20 May 2019 will be eligible to compete for the final $1 million prize.

FAQs for the Final Prize

What is required to win the final prize?

The final prize of $1 million will be awarded to the entrant that has been deemed by the judging panel to have best met the judging criteria.Winning teams are expected to have been responsible for the creation of one million square meters of cool roof material between August 2019 and December 2020, and to have a plausible accompanying model for scaling cool roofs further that is sustainable and transferable to other contexts

What if no team gets to one million square meters of cool roof material?

Should no team reach the intended target, the prize will be awarded to the team that is deemed by the judging panel to have best met the judging criteria, i.e. that has developed and evidenced the most effective and sustainable model for deploying and scaling up cool roofs, subject to a satisfactory level of progress and at the discretion of the judging panel and the Kigali Cooling Efficiency Programme.

What needs to be submitted for the final prize and how will the cool roof deployment by monitored?

Teams will need to submit evidence of their cool roof deployment to date (up to December 2020) and any evidence of impact of this deployment, as well as fill out a development plan with details of their model for deployment of cool roofs and plans for future scaling. Further supporting documentation may also be required. Forms will be provided to teams to track the deployment of cool roofs in their region, though other forms of evidence will also be admissible with prior agreement from the Global Cool Cities Alliance.

How will submissions for the final prize be assessed?

The evidence of deployment and accompanying deployment/scaling model will be evaluated by the expert judging panel. There may additionally be site visits conducted by the Million Cool Roofs Challenge team to verify deployment and assess the approach taken.

When will the winner be announced?

The winner of the final prize will be announced in March 2021, with the exact date TBC.

Who is eligible to lead a team and what does leading entail?

All teams involved in the application must meet the eligibility criteria. The lead applicant will be responsible for contracting with the challenge partners, any reporting requirements associated with this contract and managing the budget and payments of other applicant team member. The lead applicant is responsible for ensuring all team members adhere to competition terms and conditions.

How do I measure effect on UHI/energy to respond to application questions if I don't have a pilot yet?

For applications that do not have a pilot project to cite, we would look for a clear understanding of the challenges of urban heat in their target area and reference to locally relevant studies.

Are any industrial buildings eligible given the occupancy requirements?  How much occupancy is enough?

The objective of the Million Cool Roof Challenge is to benefit individuals and communities and so only buildings that are regularly occupied by people may be included, this can include residential spaces or work spaces. There is no formal restriction on the type or main use of the building beyond this, however a key part of the application will be demonstrating how projects impact as many people in the community as possible.