A student's ingenious plastic windows are helping to make homes ruined by the war in Ukraine useable again.
PhD student Harry Blakiston Houston put his studies at Cambridge University on hold to create the new windows.
The engineer has found a way to replace windows damaged by bullets and bombs with ones of his own design.
According to the United Nations, millions of people in Ukraine are "living in damaged homes or in buildings ill-suited to provide sufficient protection", particularly in the winter when temperatures can plummet to -20C.
Mr Houston said one woman in Mykolaiv, southern Ukraine, had been sleeping in her bath for two months because it was the warmest place in her house before the plastic windows were installed.
He said: "We were able to get her back to some kind of normality after the windows went in. The house was immediately warmer and lighter – she was able to rearrange everything and actually live in her home again."
Fedor Tikva, of Izyum, eastern Ukraine, said the Insulate Ukraine replacement windows have made his house liveable after his original windows were destroyed by nearby bombing.
The 64-year-old said: "Before that it was impossible to live in that house because there were no windows and it was very damp and cold there. There was no heating, the heating was also destroyed."
"All windows there were broken, even the frames partly were damaged," he said. "The walls also were a little bit damaged with parts of bombs."
He continued: "We were the same happy after the installation of the windows as we were happy when the light and gas came back into our houses after the occupation.
"So we are cheering and saying hooray."
Mr Tikva shares the house with his sister, whose flat on the other side of the city burned down during the Russian occupation.
Izyum was occupied by Russian soldiers between 1 March and 11 September last year, according to Mr Tikva.
Insulate Ukraine staff member Helen Demchenko, who translated for the 64-year-old, said new windows have been provided to more than 200 people in Izyum.
She said residents are either given materials to build the windows themselves or staff and volunteers will install them if customers are vulnerable.
The project is operating across the liberated areas of Ukraine that have "suffered the most" at Russia’s hands.
The concept uses triple-glazed polyethylene to protect against the cold, costs around £12 per square metre of window, and can be built at home in 15 minutes from basic materials.
Mr Houston said: "The level of destruction the Russians left in their wake is astounding. There’s hardly a house in Izyum without bullet holes in it. In peacetime the city was home to 50,000 people, now there are 10,000.
"Part of Putin’s war is about trying to make people in Ukraine cold and miserable. It’s about breaking their resolve to actually continue defending themselves.
"We’ve come up with a solution that makes a real difference."
The PhD student came up with the idea while queueing to see the late Queen lying in state last year.
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