More than 70 firefighters tackled a fire at a house undergoing construction work in west London.
Flames took hold at a building site in Campden Grove, Kensington, at about 06:10 BST.
The three-storey property was fully alight, with members of the public tweeting they could see smoke at Heathrow Airport, 13 miles away.
A mother and daughter were rescued from a neighbouring garden, London Fire Brigade said. Both were uninjured.
The roof of a neighbouring property also caught fire.
London Fire Brigade station manager Rhodri Horton said: "When crews arrived they were faced with a rapidly developing fire affecting the whole of a three-storey house under refurbishment.
"A mother and a daughter from a neighbouring property escaped into their garden.
"Fire crews used a ladder to get them over a fence and away to safety. Thankfully, they were both uninjured."
Ronda Challoy, the woman rescued from her garden, told BBC London: "We were about to escape from the main door but when I saw there was fire and smoke we went to the back garden.
"The fire brigade came and rescued us - we couldn't get out of the garden, so we climbed over three walls.
"It was very frightening but thank God we managed it."
She added: "My daughter is trembling and even I am trembling, but we had the energy to climb the wall."
The BBC witnessed the owner of the gutted property arriving at 09:45 BST, screaming and shouting: "That's my house."
The fire was under control by 10:30 BST.