Two prominent housing sites going for sale shortly in Dublin should give a good indication of whether values have slipped because of Government plans to compel house-uilders to make up to 20 per cent of their land available for social housing.

Hamilton Osborne King is quoting a guideline price of £6.5 million for the 3.9 acre Belgrove Club sports grounds, beside St Anne's Park, Clontarf, and £2.2 million for a site of over three-quarters of an acre along the Dodder River at Milltown Bridge, in Dublin 14. Both sites are to be sold at auction.

Officials in the Department of the Environment have predicted that values could fall by up to 20 per cent but with relatively few sites available in the suburbs and no let up in the demand for new houses, it is by no means certain that prices will fall because of the Government intervention.

The Irish Home Builders Association is expected to put forward an alternative plan for dealing with the housing crisis, suggesting that more affordable housing can be provided once higher densities are allowed. Earlier indications that the association would mount a court challenge to the new Planning and Development Bill may not now happen.

Nevertheless, some of the largest house-builders have threatened to scale back their house building operations if they are forced to hand over up to 20 per cent of their sites at a discount.

Pat Nolan of Hamilton Osborne King is still expecting strong interest in the Belgrove sports grounds, in Clontarf, which go to auction on November 4th. The land is almost rectangular in shape and is bounded on three sides by housing and to the north by St Annes Park. The site is located off Mount Prospect Avenue and Vernon Avenue, two of the most fashionable roads in Clontarf. The land is zoned for residential use and could accommodate about 147 apartments and duplex units, according to a study carried out by architects O'Mahony Pike.

In July, another site of 3.25 acres at Seafield Road East, Clontarf, sold at auction for £7.6 million - £3.6 million more than the pre-auction guide price.

The Milltown site is also zoned for housing but does not have a current planning permission. In this case, O'Mahony Pike suggested that about 36 apartments could be built on the land, where there is at present one house.