Members of the public will be able to demonstrate their support for the campaign by signing a red brick sticker and putting it on the wall, changing it from a gloomy grey colour to a more hopeful red.
The wall will be unveiled today with a 4.30pm ceremony attended by Adam Sampson, Shelter chief executive, and Des Wilson, Shelter founding director. They will turn on a sequence of projections, using the wall as a surface, that show the plight of children and their families living in bad housing, and will include children reading poems about their experiences.
The wall will be up until Sunday December 3 as part of the charity's campaign to persuade the Chancellor to fund an extra 20,000 social houses each year in England between 2008 and 2011. Shelter estimates that these could lift 150,000 children out of bad housing and give them the chance of a brighter future.
Sampson said: "It's a scandal that 40 years after the plight of 'Cathy Come Home''s on-screen family shocked the nation, the lives of 1.6m children are today being devastated by the grim reality of homelessness and bad housing."
People can also pledge their support online on a virtual wall at .
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