A Home Gym and Spa Retreat by Swift Unlimited
Published: 23 May 2026
Reading Time: 4 minutes 30 seconds
There are garden rooms, and then there are buildings that make you question why you'd ever check into a hotel spa again. This project by Swift Unlimited falls firmly into the second category. Located close to the coast in North West England, it's a bespoke wellness building that houses a fully equipped home gym and a spa retreat complete with sunken pool — a combination that delivers something genuinely exceptional: hotel-quality facilities in a private garden, available every morning before work and every evening after it.
At just under 70 square metres, this is a substantial building. It required planning permission and full Building Regulations approval, both of which Swift Unlimited handled as part of their turnkey service. That scale and that level of ambition would be challenging for many companies to deliver. For Swift Unlimited, it's the kind of brief they're built for.
A Brief That Started with a Vision
The clients knew what they wanted — a dual-purpose wellness building that would cater for serious training on one side and genuine relaxation on the other. Swift Unlimited worked alongside groundworkers, landscapers, pool specialists and architects to bring together all the elements a project of this complexity demands, completing it on time and within budget.
The layout they arrived at is elegantly logical. The building measures 13.83 metres wide by 4.81 metres deep, divided into two rooms. The left-hand space is the home gym, filled with the owner's choice of fitness equipment. To the right is the spa — a calming, considered retreat built around a sunken pool. Two smaller rooms lead off the spa: a shower room and a second space that, we imagine, functions as either a changing room or plant room. The proportions, flow and adjacency of these spaces reflect careful design thinking, not a standard template.
The Glazing and the Garden Connection
Perhaps the most immediately striking feature of this building is its glazing. The façade has a confident, unhurried rhythm: a central full-height window sits as the centrepiece, flanked on either side by rendered wall panels before the glazing wraps around each corner in wide sliding door configurations. The wide sliding doors are deliberately specified to minimise the frame-to-glass ratio — the result is a clean, considered elevation that prioritises the view rather than the structure holding it together.
From inside both the gym and the spa, the garden reads as part of the experience. Training equipment faces the garden. The spa pool is positioned so that the outlook beyond is restful and green. The glazing doesn't just let light in; it actively frames the space and connects the activities inside to the landscape outside.
Achieving the seamless threshold between interior and exterior required exactly the kind of careful coordination that Swift Unlimited are known for. The internal flooring, door threshold and exterior paving tiles all sit at the same level, with low-profile thresholds throughout. Getting this right on a project of this scale — with a sunken pool, complex groundworks and a landscaping contractor also on site — required precise planning and close communication. The finished result looks effortless, which is precisely the point.
Structure, Height and Specification
The construction follows Swift Unlimited's established approach: a multi-layered SIPs (Structural Insulated Panels) envelope with a steel frame integrated to carry the roof load across the substantial glazed spans. The amount of glazing this building incorporates places significant structural demands on the building — demands that the steel frame resolves without compromise to the architectural intent.
The building is taller than a standard garden room, offering greater floor-to-ceiling height throughout. That additional height is a practical benefit in the gym, where equipment headroom matters, and a considered aesthetic choice in the spa, where the sense of space adds to the quality of the experience. The extra height was incorporated into the planning approval for the project, with Building Control sign-off completed as part of Swift Unlimited's turnkey service.
Externally, the SIPs structure has been rendered to complement the finish of the main house — a choice that anchors the building within its setting. A natural timber fascia provides warm relief from the crisp black and white palette, softening the lines and adding texture.
A Spa at Home
The wellness room, accessed from the gym via an internal glazed door, is the kind of space that would sit naturally within a five-star hotel or high-end spa retreat. Its defining feature is a sunken spa pool, which required both complex groundwork and specialist engineering: deep excavation, significant load management, and the integration of filtration, heating and pumping systems below floor level. Swift Unlimited has considerable experience with exactly these installations, including the less visible but equally critical elements — ventilation systems, heat exchangers and air conditioning units capable of managing the demanding conditions that a spa environment creates, where chemicals, humidity and water exposure are a constant factor.
The photographs show a space with all the tranquillity and considered detailing that the brief demanded. Smooth finishes, precise tiling, controlled lighting. It has the feel of a private sanctuary, built to be used daily.
Turnkey Delivery
Projects of this complexity involve a lot of moving parts. What Swift Unlimited bring to a brief like this is the experience to design and build their element of the project to the standard that the wider scheme demands — working alongside the pool specialists, groundworkers and landscapers rather than in isolation from them. The level threshold detail is a good example: achieving the same finished height across internal flooring, door threshold and external paving required careful coordination between Swift and the landscaping team. It worked.
Pricing
At current prices, a building of this style, size and specification — with sunken spa pool infrastructure, planning, Building Control and the associated specialist installations — would typically cost in the region of £150,000 to £175,000 including VAT. This figure does not include the cost of the pool itself or associated plant equipment.
Swift Unlimited is currently working on projects across the UK ranging from £60,000 to £420,000, each tailored to the client's brief and site. Nearly two decades of experience, a commitment to high standards of finish, and a comprehensive turnkey service make them a well-established choice for clients who have a clear vision and want it delivered properly.
Learn More
To find out more about Swift Unlimited's bespoke garden rooms, annexes and extensions, visit www.swiftorg.co.uk. You can contact the team on 01625 875 588 or at support@swiftunlimited.co.uk to discuss your project.
