Free newspapers found on London's Tubes, trains and buses are to be used in an interactive art installation and stimulate debate about recycling.
Volunteers aims to collect 100 papers each
Volunteers from Project Freesheet plan to gather 10,000 copies of discarded papers which will then be used to build a house entirely from newspapers.
Artist Sumer Erek will create the house in Dalston, north London, next week.
The project will encourage people to think about how to keep the environment clean and tidy.
Up to 100 people have been out on Wednesday collecting copies of the Metro, thelondonpaper and London Lite left on the ground, in waste bins and on public transport.
They are aiming to collect about 100 newspapers each which will then be displayed outside City Hall at about 2000 GMT.
The papers will then be used as part of the interactive Newspaper House project which begins in Gillett Square on 3 March.
For seven days Sumer Erek will build a house made from newspapers found scattered around London.
The theme of the project is "the city is our home" and encourages people to think about how to keep our "house" clean, attractive and liveable.