About the Client
Tomasz is 42. He has trained consistently for over a decade – weights, some CrossFit, occasional running. For years he paid for a gym membership in town: a 20-minute drive each way, parking, waiting for the squat rack on Friday evenings. When he bought a new house with a large garden, he decided to end that chapter permanently.
The requirements were clear: a garden gym, year-round, aesthetically acceptable (his wife had a vote on what goes in the garden), capable of housing a complete strength and cardio setup, and ready in weeks – not months.
Why a Container Module, Not a Conversion?
Two reasons.
First: speed. Converting a garage or building a purpose-built outbuilding would mean planning applications or detailed prior approval, architectural drawings, a builder and months of waiting. A container module up to 35 m² qualifies as a temporary structure – the paperwork is a notification rather than an application, and we handle it.
Second: insulation quality. The Gym Box is built specifically for year-round outdoor use – 100 mm wall insulation, 80 mm floor insulation, 120 mm roof insulation. Compare that to an unheated garage in January, where temperature regularly falls below 5°C.
Siting and Foundation
The module – 10 × 3 m, 30 m² – was positioned along the rear boundary of the garden. The ground was level and required no earthworks. It was placed on a precast concrete pad. Delivery and positioning took one working day.
Services
One single 230V / 32A cable runs underground from the house at 60 cm depth. Everything else is self-contained inside the module:
- 2.5 kW split inverter air conditioner – heats in winter (rated to -15°C), cools in summer. Quiet and efficient.
- Electric underfloor heating – combined with the split, delivers full thermal comfort year-round. Particularly good for mat-based training in cold weather.
- Ceiling infrared panel – backup heating for extreme cold.
- LED lighting 3000K – warm, functional light. Adjustable across 3 zones.
- 4 power sockets + USB socket – for cardio equipment, phone, Bluetooth speaker.
- Supply and extract ventilation with heat recovery – fresh air exchange without losing heat during hard sessions.
Training Equipment
Tomasz knew what he wanted. He arrived with a list.
Strength zone:
- Multi-function cage with high and low cables, pull-up bar
- 20 kg Olympic barbell + plates to 250 kg
- Rubber hex dumbbells 5–30 kg in 2 kg increments, on metal rack
- FID adjustable bench
Cardio zone:
- Motorised treadmill with shock absorbers (commercial-grade, 2.5 HP motor)
- Stationary bike with adjustable resistance
Finishing:
- 20 mm rolled rubber flooring, grey
- Mirror 3 m × 2 m on the front wall
- Bluetooth wall speaker
- Clothing hooks and towel rail
Aesthetics – and the Approval Test
The module was finished in RAL 7016 anthracite, matching the property boundary fencing and the modern render of the house. EPDM membrane roof. Tomasz’s wife had reservations initially. After installation she conceded that it “genuinely looks like part of the garden” – not a shipping container dumped in a lawn.
The colour consultation is part of the standard process. We provide RAL swatches and can match to existing outbuildings, fencing or cladding.
Timeline
6 weeks from contract signing: 3 weeks module production, 1 week delivery and installation, 2 weeks services fit-out and equipment installation.
This is what makes the container approach different from a building project. There is no weather dependency, no subcontractor coordination, no site management overhead on the client’s side. The module arrives built. It goes on the foundation. The trades come in.