A radical programme of urbanisation is needed to defuse the "sustainability time bomb ticking away in the heart of suburban Ireland", according to the South Dublin county architect, Mr Brian Brennan.
Addressing the final session of the National Housing Conference here, he warned that the continuing fall in household occupancy levels on low-density suburban estates would lead to a collapse of key local services, including shops.
"Unless we increase average population and employment densities in our existing suburban neighbourhoods, we risk the implosion of our low-density housing model and the financial and operational collapse of our entire urban management infrastructure."
Mr Brennan said this could be averted only by creating new "urban cores" throughout the suburban environment, at three or four times the prevailing density of eight or 10 houses per acre to meet minimum sustainability levels.
This would mean "changing the character and face of suburban Ireland" - by building, for example, apartment blocks significantly higher than the two-storey norm, perhaps at the expense of demolishing existing low-density estates.
A minimum density of 40 to 50 people per acre was required to sustain local services, but falling occupancy rates as children grew up and moved out of family homes were producing unsustainable neighbourhoods with less than half the density needed.
"Neighbourhoods are the essential building blocks of the city. Without successful neighbourhoods, we cannot have successful cities," Mr Brennan said.
"High-density urban living in Ireland demands that we manage and maintain our built environment to standards never before achieved in this country," he declared. "In sporting terms, we have to `lift our game' and play like we've never played before."
Mr Arthur Hickey, president of the Royal Institute of the Architects of Ireland, said some local authorities were "turning a deaf ear" to residential density guidelines and these would have to be made mandatory to curtail suburban sprawl.
He emphasised little or nothing was compromised by building at higher densities and such schemes often had better design qualities than standard low-density suburban estates.
Mr Jim Pike, of O'Mahony Pike Architects, said Irish people suffered a severe lack of information when faced with purchasing a new home, particularly on how much it would cost to run and how it could be adapted to changing circumstances.
He told the conference there was a need to develop performance indicators, or a score sheet, for all types of housing which could be given to prospective purchasers in much the same way as if they were buying a car or a washing machine.
Mr Pike suggested a bungalow in the countryside "would have to be zero-energy and totally bio-recyclable to score half way up the chart"; this might make many of the 18,000 who moved into new houses in rural areas last year think twice about their choice.
Noting a recent survey in London had found 75 per cent of households were now occupied by just one or two people, he said a similar pattern was likely to apply in Dublin, yet the three- or four-bedroom "semi" remained the predominant form of housing.
