The British beauty, married to jazz star Jamie Cullum, took to the airwaves in the U.K. to publicise a campaign to transfer Dahl's dilapidated shed, where the beloved author wrote several of his stories, from his former home in Buckinghamshire, England to a museum.
She told BBC Radio 4's Today programme, ""It's in a bit of a state, poor little hut. It needs help. We are trying to raise half a million pounds, which sounds like a great deal of money to move the interior of a little hut but it's quite a process.""
However, her appeal caused outrage among listeners, who took to social networking sites to suggest the Dahl family should pay for the move themselves from the millions his books has earned in royalties.
One listener wrote on Twitter.com, ""Roald Dahl Day tainted by Sophie Dahl begging for public money to fix Roald's writing shed whilst his books are still selling worldwide.""
Another added, ""I love a bit of Roald Dahl. But being asked by his millionaire granddaughter to stump up for his shed being moved takes the Wonka biscuit.""
But Amanda Conquy, chairman of the Roald Dahl Museum, has defended the campaign, saying, ""If anybody from the public wants to give money that would be great but we are not expecting them to. Our requests are going to trusts and foundations. We have raised half of the money already and the point of today's announcement was to tell the world that soon the shed will be open to the public.""