Mulhuddart seems an unlikely place to unfurl the banner of higher density, socially inclusive housing. If anything, this fast-expanding extension of Blanchardstown is a metaphor for all the mistakes we have made in the suburbs, littered as it is with ghettoised low-density estates, both public and private.

But last week's launch of an innovative scheme of 703 homes, mainly two-storey houses with some apartments in three-storey buildings, was seen as so significant that the Minister for the Environment, Mr Dempsey, who has championed higher density and social inclusion, turned up to give it his personal endorsement.

What it does is to take on these challenges while at the same time creating a pleasant living environment. Public reaction to it is of critical importance if the concept of high density and the Minister's controversial idea of allocating a proportion of new estates for social or affordable housing are to gain ground. The scheme is planned for a 40-acre site, just north of Mullhuddart village, which has been owned for several years by Fingal County Council. The council could have built on it or simply sold it off to private developers. Instead, it decided to do the responsible thing and treat it as a major housing demonstration project.

Given the debate about density and the desperate need for more affordable housing, the council got together with the Royal Institute of the Architects of Ireland to organise a development package competition as part of the institute's Housing 2000 initiative - with design quality as the most important criterion.

Tender bids could not be made unless those qualities were demonstrated in the design submissions of the architect/developer consortia. The initial 25 submissions were whittled down to six by a jury representing housebuilders, architects and planners with wide experience of housing, before the winner was selected.

Designed by architects McCrossan O'Rourke for Shannon Homes, the winning scheme will provide 412 homes for sale at less than £100,000 to people who qualify for shared ownership or affordable housing, 105 for local authority tenants and 186 which will be sold on the open market to private purchasers.

What makes the scheme - on view outside the UCI cinemas in Blanchardstown shopping centre - quite unusual is not just its daring social mix, but also its density, which works out at just over 16 housing units per acre, or roughly double the density of suburban housing that's been the norm for decades.

The real impetus behind the project, as County Architect David O'Connor explained, was to allay public fears that higher residential densities equated with slums. "The winning design demonstrates that viable, pleasant housing at higher density can be a reality at no sacrifice to the privacy or amenity of families or individuals."

It is, in effect, a fully-designed visualisation of the Residential Density Guidelines issued last March by the Minister for the Environment, without any illustrations. Coincidentally, it was designed by the same architects who acted as consultants on the preparation of these guidelines - so they should know the score, inside out.

McCrossan O'Rourke's scheme is far from radical; indeed, it is conservative. There is nothing above three storeys in height, every house has its own private space - a back garden - and all of the apartments have "owndoor" access. Apart from monopitched roofs on the three-storey apartment blocks, the style is conventional.

What makes it different is the layout that higher density facilitates. All of the open spaces, including a stretch of the proposed Tolka linear park, is fronted by housing, thereby ensuring "passive surveillance". Streets, squares and crescents conspire to give the estate a more urban form and create a "village-type" atmosphere.

Parking is allocated at 1.4 cars per unit and grouped in bays on the street, in front of the houses rather than tucked in behind in the current English fashion; that wouldn't work here, because of the danger of vandalism. The estate will also be "well-served" by public transport, according to Mr O'Connor, to reduce car use.

The layout, with its emphasis on continuous streets rather than lots of cul-de-sacs, will allow buses to run through the estate's main roads; it is not an enclosure with a single entrance. Most of the streets are curved to create a greater sense of place, and priority for movement on the estate is given to pedestrians and cyclists.

Cllr Michael O'Donovan (Labour), who played a role in promoting the scheme, said the estate would be within walking distance of Blanchardstown's new institute of technology and just five minutes by bicycle from the IBM plant near Clonee.

IMPORTANTLY, there is no major differentiation between social and private housing. Though most of the private houses are concentrated at the southern end of the site (phase 2), some of them are interspersed with affordable and local authority housing (phase 1). Only the final phase will not contain any private houses.

This is radical stuff by Irish standards, so Shannon Homes Ltd is clearly taking a risk on the £42 million scheme. But at least its layout and architectural language should help to market higher densities. As RIAI president Arthur Hickey observed, it would "give people something that they recognise and still feel happy with".

In doing so, it would help to allay the "fears and misconceptions" about higher density housing. According to him, the McCrossan O'Rourke scheme "is an excellent example of how higher density schemes can be developed to fit into our suburbs", spreading land costs and helping to solve the current housing crisis.

"Higher densities will permit greater use of public transport and should mean shorter distances to shops, schools, churches and other social facilities," Mr Hickey said, echoing the Residential Density Guidelines. After all, nobody could say that Glasnevin or Terenure, built at 20 houses per acre, were not "desirable".

Brian O'Rourke, partner in charge of the design team, described the Mulhuddart scheme as "a leap forward, but not so far as to alienate the public". Among its selling points is not just the quality of the housing, but also the provision of children's play areas, a seven-a-side playing pitch and a shopping/community centre.

The mix of units ranges from one-bedroom apartments to four-bedroom homes, reflecting the current, very diverse profile of the housing market. The design team also took on board the idea of "lifetime adaptable housing" which requires, at a minimum, a wheelchair-accessible toilet on the ground floor of each house.

Given that the houses will have communal open space rather than front gardens, there will obviously be a need to restrain householders from disrupting its with boundary tacky walls and balustrades. One possible solution would be to turn it into a "managed scheme", like many townhouse and apartment complexes.

Cllr Tom Kelleher (Labour), chairman of Fingal's strategic planning committee for housing, said higher density housing in areas such as Mulhuddart was "the only way forward"; otherwise, Dublin would continue to spread out all over Leinster. And if it helped to allay fears about "ghettos in the making", so much the better.

Construction of the first phase is due to start early next year and the whole estate of 703 new homes should be finished by mid2003. Fingal County Council also has consultants working on a design guide for higher density housing, which the county planning officer, Douglas Hyde, expects will be published in the early part of 2001.