The Hyatt hotel group is to expand its residential spa concept, introducing purpose-built spa guestrooms offering a full range of treatments in all new Park Hyatt and selected Grand Hyatt properties.

The inaugural residential spa, featuring 14 spa guestrooms and suites, debuted at the Grand Hyatt Hong Kong in 2004 and was followed by residential spa sites in Bangkok and Dubai.

The first Park Hyatt to feature a residential spa experience will be in Washington, US, and Buenos Aires hotels alter in 2006 with further openings in 2007 in Beijing and Shanghai.

The concept will also be integrated at the Grand Hyatt Moscow and Park Hyatt Goa.

The dedicated spa guestrooms will range in size from 500sq ft (45sq m) to 1,000sq ft (90sq m) and allow for both wet and dry in-room treatments. The bathroom will take up at least a third of each room with other spa facilities including rain showers, treatment benches and deep soaking tubs, allowing water to spill over into the shower area.

The residential spa concept has been in development for the past five years.

The brand rollout was prompted by recent research which found that, across Hyatt’s 80-strong global spa portfolio, revenue in 2005 was US$94m (74m euro, £51m), a growth of 15 per cent on the previous year. Women represented 65 per cent of guests and massage was the most popular service, with 923,000 taking place. Details: www.hyatt.com