Environmental concerns have been neglected by ministers in their attempt to get new houses in England built quickly, a watchdog has warned.
Letchworth, Herts, describes itself as a "model" sustainable community.
Too many old homes are demolished and amenities are often not ready, says the Sustainable Development Commission.
The watchdog also urged ministers to cut carbon emissions from older houses.
The government said new planning rules make clear councils must block any development that fails to meet tough environmental standards.
"Eco towns" hits the headlines last week when Gordon Brown set out plans for 100,000 new carbon neutral homes.
Mr Brown, who will succeed Tony Blair as prime minister, said that he wanted to see five new "eco towns" created as part of a general increase in house building to meet "pent up" demand for homes.
But the SDC's report warns that while it was "hugely encouraged" by the way in which ministers were addressing sustainability, "few communities built so far are living up to the promise of being environmentally sensitive, well-connected and inclusive".
The report, Building Houses or Creating Communities?, found homes were being built in areas where there are concerns the water supply will not meet rising demand.
The government has made real progress on climate change with its pledge that new homes will be "zero carbon" by 2016, the report said, but needs to offset carbon from now until then by drastically reducing emissions from existing homes.
Some of the issues identified by the SDC report, which is based on site visits and interviews with local authorities, developers and residents, include:
- A significant amount of undeveloped land is still being used for new houses.
- Despite a change in government policy on the issue, there are still plans for extensive demolition of occupied homes in the North and Midlands, which breaks up communities and creates huge amounts of waste.
- A lack of co-ordination means some communities are left without vital facilities like community centres and bus routes when the residents move in.
- Consultation with residents has often been poor.
The commission is urging the government to connect new homes with existing communities, rather than sprawling into undeveloped land, and to remove the current VAT incentive for developers to demolish homes instead of refurbishing them.
'Not up to scratch'
The SDC also demanded water and energy efficiency should be improved in houses by installing water meters and high quality insulation in all homes, and that parks, community gardens and sports areas should be provided in all new communities.
In addition, residents should be consulted extensively about the future of their communities and co-ordination should be improved so residents get services and public transport on time, the report says.
'Attractive and affordable'
Rebecca Willis, vice chairwoman of the SDC said: "People want safe, attractive and affordable places to live.
"Despite the government's good intentions, our research shows that new communities aren't always coming up to scratch."
She said there was a huge opportunity for the government to get sustainable development of housing right.
"The priority must be to turn our existing communities into eco-towns. Communities can be green and prosperous, with well planned public transport and great facilities.
"But the government must learn from past mistakes and put residents' needs before commercial interests and housing targets," she said.
A Communities and Local Government spokesperson said that the government was committed to making sure new homes are built to a high quality design.
"That is why we recently introduced new planning rules that make clear councils must block any development that is poorly designed or fails to meet tough environmental standards," she said.
She added that green initiatives to improve the quality of houses built had been brought forward to ensure all new homes were "zero carbon" by 2016.