A 1.6 m door set sits within a 4.8 m glazed frontage, with four 800 mm fixed frames arranged two on each side.
ASHTEAD, SURREY · A DIRECT TRJ PROJECT
Garden office and gym in Ashtead
A separate space to work, train and make your own.
Designed and built directly by TRJ Construction for Paul and Hannah, this insulated garden room brings together charcoal composite cladding, bespoke black glazing and a bright, open interior. Costi and the team delivered the building from design through to the finished room.
- Location
- Ashtead, Surrey
- External dimensions
- Approx. 5.15 m × 4 m
- Purpose
- Garden office & gym
- Delivery
- Direct TRJ design & build
01 / THE BRIEF
Space for work.
Room for training.
Paul and Hannah wanted a garden building with a comfortable, flexible interior and a strong connection to the garden. The order form describes a fully insulated garden gym; Paul’s review calls it their garden office. The open plan supports both uses, with the owners free to arrange their workspace and exercise equipment.
Full-height glazing was central to the design. A pair of French doors sits between fixed glazed panels, with additional side windows bringing daylight around the corners. The black frames and coordinated transom bars give the building its distinctive frontage.
This was a direct TRJ Construction project. Costi handled the design and drawings and managed the build with the TRJ team, coordinating the structure, glazing, services and interior finish.
02 / THE DESIGN & LAYOUT
An open room.
A considered frontage.
The original order form records an approximate external footprint of 5.15 m wide by 4 m deep, equivalent to around 20.6 m². This is the external footprint, rather than the usable internal floor area.
Each side elevation has an 800 mm full-height window with an opening top section. The specified transom bars line through across the glazing.
An open interior provides space for a home office, training or a combination of both, with heating, cooling, power and lighting integrated.
Design concept illustration and original order-form layout. The concept shows an example equipment arrangement; finished project photographs appear below.
03 / THE STRUCTURE & FINISH
Insulated construction.
Details that work together.
The building uses 125 mm SIP wall panels with 150 mm SIP floor and roof panels, as recorded in the project specification. The base is reinforced for heavier equipment, while the compact footprint creates a separate room within the garden.
The project record identifies upgraded 1,550 mm screw piles. The roof has an EPDM membrane, and the projecting front canopy includes three recessed external LED downlights.
Charcoal exterior
Deluxe brushed charcoal composite cladding is fitted with matching edgings and trims. The rear uses fire-resistant board with a silicone-render finish.
Bespoke black glazing
French doors, fixed front panels and side windows are black inside and out. The order form specifies 69 mm transom bars coordinated across the elevations, with opening top sections in the side windows.
Heating and cooling
A 2.5 kW LG Mirror air-conditioning unit provides heating and cooling. Its mirrored finish is visible in the completed room, alongside the insulated SIP envelope and opening windows.
Interior finishes
Howdens laminate flooring, decorated white walls and skirting give the room a clean finish. Eight recessed internal LED downlights complement the natural light from the glazing.
Power and connections
The electrical installation includes four internal double sockets, with black fittings and USB charging. A dedicated consumer unit is supplied by approximately 40 m of armoured cable from the house, as recorded in the project specification.
Direct delivery
TRJ Construction designed and built this garden room directly for Paul and Hannah. Costi and the team coordinated the work and communicated with the owners throughout the build.
04 / CUSTOMER FEEDBACK
Paul’s experience
of the build.
★★★★★
Costi is professional, very knowledgable, always diligent and super passionate about building the very best building he can. He thinks of any problems first, communicates openly and solves problems mostly before they are an issue. His build is of a very high quality and we couldn’t ask for a better builder and team to build our lovely garden office, we recommend him very highly, probably the best builder we’ve ever worked with which, I know sounds hyperbolic, but work with Costi and his team and I would imagine you’ll be saying the same thing. I wish more people were as conscientious and hard working as Costi and his team are, absolute legends.
Paul Gygi · 5-star customer review
05 / THE FINISHED PROJECT
Inside, outside
and the finer details.
Actual photographs of the completed garden room in Ashtead. Select a photograph to see the full image.
06 / PROJECT PRESENTATIONS
The build and details,
explained visually.
TRJ’s supplied project presentations show the SIP structure, bespoke glazing and selected finishes. These annotated visuals accompany the original photographs above.
07 / PROJECT QUESTIONS
A few useful answers.
How large is the Ashtead garden room?
The original order form gives approximate external dimensions of 5.15 m × 4 m, or around 20.6 m² externally. The usable internal area is smaller.
Was this a direct TRJ Construction job?
Yes. TRJ Construction designed and built the room directly for Paul and Hannah, with Costi managing the job and the TRJ team carrying out the build.
Can it be used as an office and a gym?
The room has an open layout, reinforced base, lighting, sockets and heating and cooling. The project was specified for gym use and Paul describes it as their garden office.
How is the room heated and cooled?
The project includes a 2.5 kW LG Mirror air-conditioning system, alongside SIP floor, wall and roof construction.
YOUR NEXT PROJECT
A room for
your working day.
Planning a garden office or home garden gym? Tell Costi how you want to use the space, the area available and the details you would like to include.
Explore our build process and planning guidance, or browse more Home Offices projects.
