Triangle House
Triangle House is a detached home at the end of a cul-de-sac overlooking Roseberry Park in Epsom, developed by Ideal Homes in the 1950’s. Artefact created a new wing to the house that chases the afternoon sun at the back of the garden. Crafted from triangular blue blocks and terracotta tiles, with a warm yellow ceiling, the extension references the tones of the existing house and the client’s heritage, inspired by the book Caribbean Style. The vibrant architecture is framed by an exotic planting scheme by Phenomena, as banana palms and lush planting unfurl along the sweeping blue terrace that unites the existing house and the extension.
The client’s brief was to create expanded living spaces, a new family bathroom, a future proofed adaptable bedroom, an office-cum-music room, a snug and a reconfigured garden. Artefact translated these requirements into a series of interconnected spaces that flow from the street through to the garden. The new entrance is marked by a canopy, supported on a triangular column that references the detail of a mid-century building in the surrounding neighbourhood. Beyond the low canopy, the entrance lobby is a dramatic double height space where old and new collide under an open mezzanine and family bathroom. Passing through the hall, an enfilade of living spaces unfolds along the garden, culminating in a picture window that frames a view over the park. Designed without internal doors, the kitchen flows through a pair of openings into the top-lit dining room which leads on to an intimate snug at the end of the enfilade. A careful balance of openness and enclosure ensures the living spaces feel like a series of distinct rooms with glimpses of life in the neighbouring spaces.
With an ambitious brief on a tight budget, Artefact skimmed the fat of the building, developing a lean material strategy that gives the building its character, while reducing the cost and carbon of the construction. Single leaf walls are constructed from hollow fairfaced blocks, exposed internally, with insulation and render to the outside. Exposed timber beams and OSB sheathing board are expressed and painted in a bold yellow. In the tradition of public facing buildings with a more ornate civic façade, the garden elevation is more expressive than the utilitarian rendered walls to side and rear. Off-the-shelf blue pigmented blocks were skilfully cut on site by the contractor to create deep triangular columns, with inset terracotta tiles that echo the hung arrowhead tiles of the original 1950’s house. This triangular motif recurrs across the project, from the shape of the plot and the canopy column to the patterning of the original mid-century wallpaper.
A key ambition at Triangle House was to reduce the number and volume of materials, resulting in a lean yet robust building with a distinctive material character. For example, internal doors were designed out, resulting in a series of free-flowing yet distinct spaces. Timber beams and OSB sheathing board are exposed to the soffit, and blockwork surfaces to external walls celebrated rather than boarded and painted.
Crucially, the project explores an efficient way of building external walls. Cavity wall construction remains the default in the UK with facing brick to the exterior, and an inner leaf of block, plasterboard and paint. Triangle House was constructed from a 140mm single leaf of hollow blockwork, sourced from the UK, with mineral wool insulation and render to the outside. The internal walls act as ‘piers’ to allow the walls to remain thin whilst defining the spaces. This strategy reduces the volume of masonry required by over 50%, brings down the embodied carbon, reduces the transport associated with two suppliers, simplifies the construction, lowers the cost and thins the wall by 90mm, allowing you to build less to achieve the same area.
