'We spend a lot of time watching changes in the garden and sky,' say the owners of a period house with a smart contemporary extension. Emma Cullinanreports.

THE giant city garden, behind this 1823 south Dublin house, used to be accessed through a tall window in the kitchen. That was how houses were often designed back then: grand rooms were to the front while small, dingy wet spaces - bathrooms, sculleries, kitchens - were all sent to the back to accommodate activities that were to be hidden from public view (such as cooking and unmentionables in the bathroom).

The owners of this house, who have lived here for 20 years, have long lunches with their four children and five grandchildren on Sundays and found that everyone congregated in the small back kitchen, with its 1960s units. They preferred this to the beautiful, classical but somewhat cold and dark diningroom to the north-east-facing front of the house.

The couple had already opened up a lower ground floor room near the kitchen, to a design by architects (and friends) Mary and Peter Doyle, by taking out half of the floor above it to create a gallery with views across the now double-height space out to the garden.

The latest home improvement is an extension to the kitchen, which has symbiotically linked the exterior and interior despite the fact that the new room hovers above the garden.

While the neighbours have opted for a Victorian-style conservatory to extend their house, the owners of this home were keen not to add a generic "period style" decorative object to their 200-year-old property, whose tall windows and towering chimney stacks are part of its lofty design.

They brought in architect Manfredi Anello of Anello Architects because of his conservation credentials. And, as he sweetly puts it, his clients were modern thinking - "but more 1970s" than futurist.

That is an interesting addition to the debate over whether people should opt for Classicism, Modernism or look to the future: there are plenty of other decades in which many of us felt comfortable.

That is not to say that this interior is 1970s in style but it doesn't shout or try to be iconic. Instead it is a neat, robust, friendly room that flows well from the existing kitchen and takes you almost seamlessly (the interior floor is flush with the deck) outside to float above the garden, supported on galvanised girders and columns.

The extension room itself is a smart steel-framed structure with timber floor, oak yacht decking imported from the UK and a 3m-high folding glass wall from Solarlux Aluminium Systems in Germany. This is framed with powder-coated aluminium that matches the fascia above.

But the lower part of the extension is consciously of the garden: its galvanised girders and uprights spell functionality as does the garden equipment stowed beneath the floor, turning the space into an effective garden shed. The hovering room, complete with a thickly insulated floor, enables the underside to be ventilated by west winds coming across the garden.

"It is useful to build off ground, as it is always ventilated," says Anello, who designs with an eye on the weather. The overhanging extension roof not only provides a rain-protected link between indoors and out, it also shields high and low seasonal suns. "In Ireland the sun comes from all directions," says Anello who hails from Palermo where presumably the sun is always high (he comes from a family of conservation architects and has worked on ancient monasteries and churches in Italy).

The well-insulated extension wall that faces onto the side alley has been faced with breathable lime wet-dash and is protected by an overhang at the top of the wall, which should help preserve its whiteness.

"I am always aware of driving rain," says Anello who points out that there is actually more rainfall each year in Palermo than there is in Ireland, with a heavy Sicilian downfall in one day trumping a year's supply here.

The alley-edge of the extension steps out to meet the wall at the front of the house to ease the flow between new and old by enabling the recent addition to read as a rectangle.

The new room protrudes from the southern end of the house, continuing a gradual stepping out that runs across the whole width of the back of the house.

Anello begins his projects with a vision of what he wants but says that he is happy to change things as they evolve along the way.

That perhaps sounds dangerous to people who want projects to come in on time and a tight budget but it recalls a time when things were sometimes done more slowly.

The clients were closely consulted along the way, with Manfredi insisting on features that he considered important while letting them take the lead on other areas, such as the internal floor not matching the decking, because the yachting timber was very expensive.

THE clients also helped to find the double-glazed-wall supplier on Google: while it was easy enough to get 2.4m high wall systems, the off-standard 3m was harder to find and was eventually tracked down to Germany and fitted by Bowman Aluminium, based in Co Down, who are more used to fitting them onto showrooms.

The key for architect and clients was to find a folding façade without a cross bar and the clients say that the black uprights in the glass don't bother them at all. Anyway, with that overhang and the very swish mechanism, it only takes the slightest excuse to open up the walls, wherever the sun may be.

The off-set support column sits out from the glazing, so once the glass is opened the kitchen completely loses two walls and corner support, and becomes part of the wider world.

"It has completely changed our lives," says one of the owners. "We spend a lot of time here and watch changes in the garden and sky."

A white Aga sits in the centre of the new gloss kitchen, whose layout was created by Anello, showing in microcosm how a contemporary extension can work with a period house.

The new part fits so well with the old but also looks as if it could be easily detached: all part of the melding and distinction between past and present that good conservation requires.

While being closely involved, the clients have also given their architect the freedom to create a special structure.

On the day I visit, they are still consulting him: one of the owners is having trouble with a minestrone soup he is cooking and turns to Anello, who gives constructive advice.