TRJ CONSTRUCTION · PROJECT PORTFOLIO
Granny Annexe in Cheshunt
A 9 × 3.6 m SIP granny annexe in Cheshunt, with a separate bedroom, sitting area, kitchenette, shower room and LG heating and cooling.
THE PROJECT
From an idea
to a real space.
A 9 × 3.6 m SIP granny annexe in Cheshunt, with a separate bedroom, sitting area, kitchenette, shower room and LG heating and cooling.
TRJ Construction built this annexe in Cheshunt, Hertfordshire for Lynn, creating a separate garden living space with a bedroom, sitting area, kitchenette and shower room.
Size and layout
The building measures 9 × 3.6 m externally, an overall footprint of 32.4 m². The original drawing places the sitting area and kitchenette at one end, the shower room in the centre and a separate bedroom at the other end. French doors open into the sitting area, with a separate glazed entrance serving the bedroom.
SIP structure and exterior
SIP panels form the floor, walls and roof. The order specifies screw-pile foundations with an increased-depth allowance, subject to the soil report, engineering and building-control requirements. Supporting beams were specified over the larger openings and for the main roof.
Vertical anthracite grey RAL 7016 composite cladding finishes the front, with a front canopy. The sides and rear use fire-retardant boards with a rendered finish. A membrane, battens and wall ventilation form part of the external build-up. The roof has an EPDM covering and black round guttering.
Doors and windows
The uPVC joinery is anthracite grey outside and white inside. The front includes 1,600 × 2,100 mm French doors with fixed side glazing, plus an 800 × 2,100 mm glazed single door and adjacent glazed panel with a top-hung opening. A 1,000 × 1,000 mm side window and a 600 × 600 mm obscure-glass rear window provide additional light and ventilation. Toughened, argon-filled glazing and trickle vents were specified.
Kitchenette and shower room
The kitchenette specification includes a sink, tap, 1,000 mm sink base unit and worktop, with space beneath for a small fridge. The separate shower room includes a shower enclosure, WC and basin, extractor fan, towel radiator and surface-mounted LED light.
Interior, heating and electrical installation
The interior is plasterboarded, skimmed and painted white with Dulux paint, with Howdens laminate flooring, white skirting and Howdens four-panel internal doors. A 2.5 kW Wi-Fi-enabled LG inverter air conditioning unit provides heating and cooling, supported by a 1 kW Haverland wall radiator.
The electrical specification includes seven white double sockets, fourteen internal downlights, five exterior downlights, a separate shower-room LED light and a fire alarm. An independent consumer unit with RCBO and surge protection, water and electricity connections, and an upgrade to the main house distribution board were included. The final order also records additional decking and shingle work.
CUSTOMER REVIEW · 5 STARS
Over the moon with the Granny…
“I couldn’t be happier with the Granny Annex and it has far exceeded my expectations! From the initial planning stage right through to the day I got the keys Costi and his team were there. Costi’s years of experience and expertise are evident and his attention to detail is excellent. I wouldn’t hesitate to recommend his company TRJ and everyone I have shown the annex have been very impressed.”
Lynn Sapsford · ★★★★★ · 24 July 2025
REAL PROJECT PHOTOGRAPHS
A closer look
at the build.
Explore photographs from this project using the rotating gallery. Use the arrows or pause the movement to study each view.
View the full photograph collection ↓Photograph 1 of 4 · Project photograph 1
THE PHOTOGRAPH COLLECTION
Details worth
a closer look.
Photographs recorded for this project. They may show different stages and views; the gallery is not a promise of a standard package.
View 1 more project photographs
YOUR NEXT PROJECT
Start with
your own brief.
Tell us how you want to use the space, where it will be built and which details you like from this project. We can discuss a layout and specification suited to your property.
Access, ground conditions, services, planning and building control requirements need to be assessed for your site. Dimensions, prices and timescales are agreed for the individual project.
