Garden granny flat
An L-shaped 47sqm home built within a metre of the boundary — fire-resistant board on the sides, cedar at the front, and a sedum roof over the lot.
Executive Garden Rooms are experts in designing and building bespoke garden granny flats. They provide a fully managed service, overseeing every stage from design to handing over the keys to the new home.
Each project is unique, with no standard designs. Executive Garden Rooms work with each family to determine the ideal size, layout, and specification, tailoring the design to meet their specific needs.
Once the design is agreed upon, they manage the planning application and arrange building control approval. From the initial groundwork to the final decoration, their team oversees every aspect of the build.
At a glance
- Size and shape: L-shaped, 47 square metres — open-plan kitchen and living space, a double bedroom and a good-sized shower room.
- The kitchen: a U-shaped kitchenette with a breakfast bar, eye-level oven, induction hob and extractor, fridge/freezer and generous cupboards.
- Water: a 125-litre pressurised cylinder feeding both kitchen and shower room, so the pressure holds — one of the few companies offering it.
- Insulation: rigid foil-backed — 140mm in the walls, 100mm in floor and roof, with double-glazed aluminium doors and windows. Two wall panels heat the living space.
- Cladding: fire-resistant Cedral board on the side and rear walls because the annexe sits within a metre of the boundary, Western Red Cedar at the front, UV-oiled in the factory.
- The roof: sedum, laid as part of a multi-layer system — extra insulation, and a habitat for birds and insects.
- Groundworks: a reinforced concrete foundation, 25 metres of trenching and a pumping station, all to Building Control standards.
L-shaped granny flat
Executive Garden Rooms were commissioned to design and build a self-contained home for their client’s mother. She wanted to maintain her independence while being close to her family for peace of mind.
The chosen design is L-shaped, offering 47square meters of living space. It includes a spacious open-plan kitchen and living area, a double bedroom, and a well-sized shower room.
The kitchenette has been cleverly designed in a U-shape to make the most of the available space, providing ample workspace and a breakfast bar for dining.
The kitchen features an eye-level oven, an induction hob with an extractor fan, and a fridge/freezer. Generous storage cupboards complete the design.
Pressurised shower system
A 125-litre pressurised water cylinder has been installed in the annexe, supplying hot water to both the kitchen and shower room. Executive Garden Rooms are one of the few companies to offer this type of system, which provides consistent water pressure. This ensures there’s no risk of the shower pressure dropping when water is used elsewhere in the main house. The installation also includes a convenient airing cupboard.
The shower room features a spacious shower tray with a glass screen, fitted with a Mira mixer shower that includes both a large shower head and a handheld attachment. A contemporary vanity unit complements the toilet, and a heated towel rail adds comfort. Stylish tiles have been laid on the floor.
Highly insulated granny flat
This granny flat is highly insulated, with rigid foil-backed insulation throughout. The walls contain 140mm of insulation, while the floor and roof each have 100mm. Combined with double glazing in the aluminium-framed doors and windows, the annexe is easy to keep warm.
Calculations showed that just two electric wall panels in the main living space, one in the bedroom, and the heated towel rail in the shower room are sufficient to heat the building comfortably.
A sedum roof offers many benefits
The roof has been finished with a sedum covering, which forms part of a multi-layer system. Sedum roofs not only provide year-round visual interest, but they also add extra thermal insulation. They help absorb moisture and carbon dioxide, offering a habitat for birds and insects. Over time, the plants will continue to establish, enhancing the roof’s appearance. Sedum roofs are also low-maintenance, making them an attractive option.
A mix of external claddings
Two types of external cladding have been used on this building. As the annexe is sited within one metre of the boundary, the side and rear walls have been clad with fire-resistant Cedral boards, a cement-based, pre-coloured product that requires no maintenance and offers a high fire resistance rating.
The front walls are clad in Western Red Cedar, a popular choice for its aesthetic appeal. Left untreated, Cedar weathers to a silver-grey colour over time, which can be uneven. A UV oil has been applied to slow this process significantly. Executive Garden Rooms applied the oil in the factory, ensuring all surfaces were coated. At Garden Room HQ, we have UV-protected Cedar and find that applying the oil every few years keeps the appearance fresh and is quick and easy to do.
Groundworks and connections
As part of their project management service, the Executive Garden Rooms team handled all groundworks, ensuring they met Building Control standards. These included installing a reinforced concrete foundation and digging trenches to connect water, sewerage, and electrics to the mains.
The project involved digging 25 metres of trenches and installing a pumping station. Executive Garden Rooms favour this approach over macerators, which can require more long-term maintenance.
Learn more about Executive Garden Rooms
To find out more about creating a self-contained living annexe, contact the Executive Garden Rooms team on 01202 874 766 or email them at info@executivegardenrooms.co.uk. Visit their website to learn more about their annexes.
