‘Now you can have rest in your home’: the mirror roofs cooling homes in Freetown

In 1990, Freetown was home to 529,000 people but its population has since swelled to about 1.3 million.

Mohamed Koroma has lived in the Kroo Bay waterfront community in Freetown for more than 50 years but cannot remember a time when the weather has been as hot as it was in the first few months of 2024. In that period, he and many others in the Sierra Leonean capital had to cool down in their baths and sleep on their verandas.

“Those that can afford to, they bought electric fans,” said the unemployed 61-year-old. “Those who cannot afford [them] you just leave your body like that.”

A heatwave hit parts of west Africa from February until April, with temperatures of between 30C and 40C- but with intense humidity, which residents say made them feel things were 10 degrees hotter.

The city is crowded. In 1990, it housed 529,000 people but has since swelled to an estimated population of 1.3 million.

“When I was 15, 16, we had enough space to even play football … but presently, due to urbanisation and other [reasons], the area has been crossed out with houses. Children do not have any place to play now.”

Many say that during the hottest months they resorted to spending the night on verandas, as the interiors of their homes were too hot, even for those who had fans or air conditioning.

Muctar Koroma, a 32-year-old law student and journalist, has an air conditioner but it could not cope with the intense heatwave this year. “It couldn’t contain the heat in the room,” he said. “This period was hard to withstand for many parents who have children and sick patients who had to sustain their health conditions.”

As Koroma scrolled through social media to distract himself from the lingering heat even while outside, he could see his neighbours on their verandas too, all hoping to find some relief from the heat.

Part of the problem is that the city’s expansion has triggered massive deforestation of the natural land cover and hotter weather, said Eugenia Kargbo, who was appointed chief heat officer by the city’s mayor in 2021. “The trend analysis that we did recently … shows that temperature is rising at an exponential rate across different communities in Freetown,” she said.

More than a third of the population live in the 82 informal settlements scattered around the city, some along the coastline, and city officials say they are the worst affected by the impact of the climate crisis.

In Kroo Bay, the largest of them all, there are more than 18,000 people, according to the Sierra Leone Urban Research Centre, and they often lack essential services such as water, electricity and waste management.

Koroma, for example, lives in a 10-room bungalow with his wife and three children. His two brothers also live there: one with three children, the other with his wife and one child. A few other non-relatives also live in the building as tenants.

“The structures are not designed to cope with the level of heat that we are facing. Most of the doors and windows are very small and …[about] 90-95% of the materials used to construct [them] are corrugated iron sheets, and these are heat-trapping materials,” said Kargbo.

Since her appointment, Freetown city council has been experimenting with different ways to help residents cope with extreme heat as the climate emergency affects a country ranked as the 18th most climate-vulnerable on the Notre Dame global adaptation index.

Kargbo’s office has been planting trees, a tough endeavour in a city where available land is often snapped up for housing. To protect women selling in the city’s 42 markets – mostly open-air street stalls – from extreme heat, polycarbonate shades were installed in some of them, in partnership with Climate Resilience for All.

After the materials were damaged by a windstorm, city officials are now seeking alternatives that can withstand multiple climate risks.

But another of the cooling initiatives has had more success. In Kroo Bay, a few dozen households now have new heat-reflective roofing sheets made from recycled plastics in a pilot programme – which will be expanded to cover 35% of residents across all informal settlements in Freetown. The sheets are being applied on to existing roofing sheets and on new buildings.

Temperature sensors are being used to capture data from the houses where the mirror sheets have been installed. And there is constant research, testing different techniques and technology to improve and scale up cooling within the informal settlements.

While a full evaluation will be made by the end of the year, officials say initial results show reductions in house temperatures by as much as 6C.

The residents agree. “It’s actually nearly one year now since they [the council] installed for me and some of my neighbours,” said Koroma, who is also vice-chair for Kroo Bay community. “It has already created envy because some neighbours do not have [but] for those who are privileged to get it, there is some amount of relief. [Now] you can have rest in your home.

“I actually want to advocate for the other people that do not have [the mirror roofing], if only there is support for the organisations that bring in this pilot, because that would be good for the community.”