Architect-designed spas are all the rage at the moment. Now Kelly's Hotel has one inspired by Roman baths. Emma Cullinan reports

Creating a calming spa is stressful. Today's relaxation seekers appreciate a multitude of features, including hydrotherapy pools, ice jets, saunas, treatment rooms, seaweed baths and beautiful surroundings. Perhaps that's why Irish architects are increasingly being called upon to create hard-working retreats.

This year, architectural practice Oppermann Associates won an RIAI exhibition award for their Samas spa at the Park Hotel in Kenmare, Brian O'Halloran Associates is working on the K-Club Spa due to open on December 1st, and Quilligan Architects has seen the realisation of a spa at Kelly's Resort Hotel in Rosslare.

Spas in Ireland cover a wide field from certain "day spas" which involve a couple of bubble-jet baths and a sunroom above a downtown shop, to the increasingly sophisticated oases often attached to hotels.

Quilligan Architects has been designing for Kelly's Resort Hotel since the late 1980s, helping it continue its growth from the original tearoom that opened in 1895. Since then the building has crept along its site betwixt road and sea, and has expanded widthways too, with additions on both the sea side and road side.

Fifteen years ago Quilligan Architects designed a pool area at the north end of the hotel and it was originally decided to put the new spa, and two floors of 16 bedrooms above it, next to this pool. In terms of plant and plumbing, that made sense, but during discussions it emerged that chill-seeking adults and thrill-seeking kids don't mix well. So the new spa is right at the opposite end of the hotel in orientation heaven.

Large windows in the reception and a glass elevator overlook the sea to the east, enabling any sun to alight on the spa in the morning. Then it swings around to the south-facing outside deck and garden during the day, and later shines into the new west-facing bedrooms, with their ample windows.

Some corner bedrooms have a stepped out glass bay which gives residents a view to the sea at the rear, by standing or sitting in this box. It takes a canny hotel owner, and clever designers, to give guests the oft-demanded sea view from the wrong side of the hotel.

Hotel director Bill Kelly plunged into the spa project with vigour, researching various spas outside Ireland (yes, a difficult task) and bringing consultants E'Spa on board (their products are used in the new spa, along with Clarins cosmetics). His initial decision to open a spa was prompted by a visit to Hong Kong five years ago where he noted that there were more reflexology bars than drinking bars. "I knew there had to be something in this, they couldn't all be mad." Spa actually means health through water, or Salus Per Acquam.

A visit to the Roman baths in Bath inspired Bill and the finished project in Rosslare has the air of a Spartan spa created from natural materials and sublime shapes, such as the circular tiled shower walls and an elegant pool that extends out through a glass wall. Outside, the steaming sea water in the pool rises into the cool autumn air.

The water spills over the edge of the pool and this, combined with the pool's disappearance out through the wall into a garden planted by landscape designer Sandra Cosgrove, is designed to create an air of disappearance into infinity, says project architect Kirstin Simpson.

The spa and accommodation block mark the end of the Kelly's site: there is nowhere further along to build and so the architects have created a bookend.

The gradual lengthening of the hotel over the years has been akin to the creation of a "sliced pan", they say, and the designers didn't want the new structure to look as if it could be added to.

While it fits well with the existing structure, not least in the limestone elements that match the colour of its neighbour, the new part is a superior addition in terms of design. Externally there's a creative mix of sandstone panels, limestone and timber. The space needs of the spa were greater than those of the 16 rooms above, so the spa area extends beyond the floors above.

This has been achieved by adding on blocks, including one for the sauna and one for the pool. The final result has allusions to Reitveld, and other early 20th century designers, with its jutting blocks, and shooting planes, such as the overhanging roof and that wall-busting pool. Sticking with the Dutch De Stijl movement, even certain window divides have a touch of Mondrian.

Yet this building uses softer elements and colours than these earlier examples, both on the exterior - with the timber, sand and limestone - and in the interior where natural materials are in keeping with the spa's location.

The vision was to make this spa of its place: east coast Ireland. To this end it's resulted in real and honest spaces, says architect Paul Quilligan, that relate to the sea.

"When people go into the spa I want them to feel that they are by the sea and have that enjoyable feeling you get on the beach, before they even have any treatments," says Bill.

So the materials in the building are nautical and natural, with tiled surfaces, stone and pebble floors, walls with a sand-like render and timber.

Spa design involves creating moods, so the reception area is bright and lively, with the spaces off it gradually getting quieter and darker the further you move into the building. The treatment rooms are on the first floor away from the noisier pool area, but for those of us who find all that relaxation stuff boring, the tactile surfaces underfoot, the massage jets, inviting pool and a relaxation room divided into bright and dark areas cater for more lively clients.

There's even a double treatment room so duos can be mudwrapped side-by-side. The communal aspects are in keeping with Kelly's being a resort hotel for families, says Bill (but there is a separate women's relaxation room).

So Bill Kelly and Quilligan Architects have realised their vision of a spa that is of its place but, unlike the rest of the hotel, this exquisitely designed pleasure palace heralds 21st century Rosslare.

For information about spas in Ireland log onto www.irelandhotels.com or  www.healthfarmsofireland.com