Fingal's offices are greenest of all

If An Taisce, the Green Party and local residents had their way, the Fingal County Hall might never have been built. They wanted to keep the small park opposite Swords Castle, even though it had become a venue for what are politely described as "anti-social activities". Fortunately for Fingal, they lost. Like the other local authorities in Dublin, Fingal County Council wanted its own headquarters. Remaining in the grim office block on O'Connell Street, where so many dirty deals were done, was not a long-term option.

A base had to be established in the designated "county town" of Swords, on its main street. The civic functions of the building precluded an out-of-town location so the council decided, after much deliberation, that the town park - opened in 1989 by Ray Burke - was the right site, even though few believed its stand of mature evergreen oaks could be saved. But the trees have survived, providing a wonderful green foil for what must be the "greenest" office block in Ireland.

David O'Connor, the Fingal County architect, proudly points out that the building differs little from the 1996 competition-winning entry by Bucholz McEvoy Architects in association with the Dublin office of BDP. Standing five storeys high and with its impressive glass front, the County Hall not only makes a statement about Fingal's aspirations for "an open and transparent expression of local government", it also provides highest-quality working space for 450 officials and a grand modern council chamber for 24 elected representatives. It is a complex building, finely engineered, but at the same time simple. Instead of expensive air-conditioning, it relies almost entirely on natural ventilation to provide a comfortable working environment.

If there was such a thing as fourth-generation offices, the Fingal County Hall would surely take the title. Windows on the top floors are automatically operated but it is possible for workers to open lower-level windows as well as air vents next to their desks. This element of personal control was important to the designers as an antidote to the "sick building" syndrome. It gives the lie to all the estate agents who insist that office buildings must be artificially ventilated - something Mr O'Connor believes is unnecessary in Ireland, apart from being a waste of money. Mechanical services accounted for just 17 per cent of the £13.4 million cost of the building, compared to twice that for a conventional office block. Chicago-born Merritt Bucholz and his partner, Karen McEvoy, the two young architects who were the brains behind the original concept, have put their hearts and souls into this grand project, toiling over every last detail of it for three years on the top floor of BDP's offices.

So has Donal Friel, who heads BDP in Dublin. "It did not happen casually. Throughout, there was a fair degree of pressure on Hegartys, the contractors; it was not all sweetness and light." One of BDP's main inputs was to work with Bucholz McEvoy in "fine-tuning" the north and south elevations of the three parallel wings. Conversely, the job that faced BDP's mechanical engineers was to "design themselves out" of the project by eliminating standard services. At the front, facing west, the building forms an arc around the trees, which include a wonderful specimen of Himalayan cedar. The building's chief glory, however, is the full-length glass wall.

This was engineered by RFR in Paris, who made the Louvre pyramid, and was installed by a team of Italian craftsmen. Made from 15 mm thick glass, it is suspended from what Merrity Bucholz describes as "dolphin beams" in the roof and held in place by cable trusses that span the length of the atrium - a stunning sight.

"One of our fundamental objectives was to create a very transparent building, in line with the competition brief," he says. "We took that very literally and have relentlessly pursued it." And because the trees are so close, there was no need to create an internal garden, as in Wood Quay; indeed, they have almost become part of the building.

The curve in the glass wall allows it to pick up reflections of the building during the day, while in the evening, after dark, passers-by can enjoy a full view of the atrium as they walk through the open space in front. From a distance, it presents a colourful spectacle, unlike anything else in Swords. Oak shutters are being installed on the plate glass fronting the council chamber to deter those who may be tempted from making faces at the councillors as they rezone more land, while the oak balustrade in the public gallery is to be replaced with glass so people can see better.

The "political wing" to the rear is also being filled out to provide more space. The council chamber, with its quintessentially circular layout and panoply of electronic gizmos, is the only part of the building that is air-conditioned, perhaps because so much hot air is generated there. Works of art are being commissioned for its bare white walls, including a piece by sculptor Vivienne Roche. As if to emphasise the marriage of the building with its surroundings, the green slate paving on the plaza is carried through into the atrium and even the floors of the lifts. A hotel-style reception desk, which facilitates wheelchair users, greets visitors. Offices and meeting rooms off the atrium are all equipped with clear glass partitions rather than solid walls.

The suite occupied by the county manager, Willie Soffe, is the biggest of them all, but he deserves it for sticking with the plan.

As previously reported, the building is now too small to accommodate all 600plus of Fingal County Council's administrative staff. The plan is to locate the Roads and Housing Departments to a new building in Blanchardstown, where the council needs to have a visible presence. District offices are also envisaged for Balbriggan and Baldoyle. Bucholz McEvoy have been commissioned to design a new headquarters for Limerick County Council in Dooradoyle, largely on the strength of their Swords project, which Mr Friel summed up as "a very finely engineered piece of architecture".

The only casualties of the Fingal County Hall, apart from a couple of trees, were the residents of two-storey houses to the rear, who must now live next door to this relative behemoth. Each of them received an ex gratia payment of £1,800, which is not much compensation, but at least they can admire the freshness of its architecture, up close.