Dunster House Dominator Garden Offices
Published: 21 January 2026
Reading Time: 4 minutes
For buyers who are comfortable taking on a self-build project, flat-pack and panel-based garden offices can offer a significant saving compared to fully installed, turnkey buildings. The Dominator range of garden rooms by Dunster House is designed specifically with the DIY market in mind, combining a high level of specification with a delivery and build system intended to be accessible to competent self builders.
Rather than paying for a full installation package, the Dominator range allows buyers to take control of the build, choosing the size, layout and level of glazing that suits their needs, while keeping overall costs down. It’s an approach that will appeal to those who want a garden office but are happy to manage the installation themselves.
It’s important to note from the outset that electrics are not included, so buyers should budget separately for a qualified electrician to install power and lighting once the building is assembled.
Designed for DIY Assembly
Dunster House has built the Dominator range around a panel-based construction system that removes much of the complexity associated with other types of self-build timber building. The walls, roof and floor are supplied as pre-made panels, meaning there’s no need to construct stud walls or assemble doors and windows on site.
All fixings are included as standard, along with comprehensive pictorial instructions. For those who prefer additional guidance, Dunster House also provides build videos, making the process manageable for first-time builders. While the buildings are designed to be assembled by a competent DIYer, some buyers may still choose to bring in a local carpenter or handyman to help with installation.
Sizes Options
The Dominator range covers a wide span of sizes, starting at 3.5m x 2.5m and extending up to 7.5m x 3.5m. This allows buyers to create anything from a compact home office to a larger space suitable for creative work, exercise equipment or multi-purpose use.
Flexible Panel Configuration
The Dominator range offers a good level of layout flexibility. Buyers can choose where to position windows and doors across the front and side walls, allowing the building to be tailored to the garden layout and intended use.
- There are a few practical rules to be aware of:
- Doors and fully glazed panels cannot be placed on the back wall
Dwarf windows must sit between two solid panels
Aside from these restrictions, panels can be swapped around to create a layout that works for desk positioning, gym equipment or views into the garden.
Double Glazing Supplied as Standard
The Dominator range includes uPVC windows and doors as standard, rather than offering them as optional upgrades. Glazing is supplied as 28mm double-glazed sealed units with toughened glass, designed to reduce condensation within the unit.
Frames are available in white as standard, with an Anthracite Grey option for those wanting a more contemporary look. Wide-opening uPVC French doors provide straightforward access, which is useful when bringing furniture or equipment into the building.
Insulation and Everyday Comfort
The Dominator range is intended for regular use rather than occasional fair-weather use, and insulation is included as part of the standard build up.
The walls use a 25mm multifoil insulation system within the panel build-up, finished internally with Fermacell boards. This provides a wall U-value of 0.7 W/m²K, offering a clear improvement over log cabin style garden offices that rely largely on solid timber thickness alone.
For buyers who want to improve thermal performance further, an optional upgrade adds 25mm of polyisocyanurate (PIR) insulation to the walls alongside the multifoil. With this upgrade in place, the wall U-value improves to 0.45 W/m²K, helping the space warm up more quickly and retain heat more effectively.
The roof uses insulated Izo Panels with a rigid PIR core, achieving a U-value of 0.21 W/m²K, while the floor is formed from pressure-treated bearers supporting insulated floor panels to help reduce heat loss through the base of the building.
Moisture Control and Floor Construction
Moisture management is an important consideration in insulated garden buildings. The Dominator range addresses this through its floor build-up and ventilation design.
Pressure-treated bearers form the base of the structure, supporting composite floor panels that incorporate insulation and a moisture-resistant deck. Trickle vents in the windows and doors help reduce the build-up of condensation when the building is closed.
Interior Finish and Decorating
Internally, the walls are lined with Fermacell fibreboard, supplied unpainted. This allows buyers to decorate the interior to suit their own preferences, whether that’s paint or wallpaper.
As with most new surfaces, some buyers may choose to apply a primer before decorating, depending on the finish they want to achieve.
Allow for Electrics
Power, lighting and heating are not included with the Dominator range. This allows buyers to design their electrical layout exactly as they want, but it does mean budgeting separately for a qualified electrician once the building is assembled.
For DIY-minded buyers, this is often an acceptable trade-off in return for the overall cost saving.
Learn More
If the Dominator range feels like the right route for your project, Dunster House allows you to configure the building directly on their website, choosing your preferred size, wall layout and glazing options. If you’d rather talk things through, their sales team can also help guide you through the available configurations and answer practical questions about delivery and assembly on 01234 272 445.
