To replace a leaky conservatory, architect Taro Tsuruta devised an Acoya timber structure within a faceted, glazed roof.

Exterior of timber frame conservatory with faceted, glazed roof by Taro Tsuruta

Image: Exterior of timber frame conservatory with faceted, glazed roof by Taro Tsuruta, Ståle Eriksen

What was your brief?

Interior of a timber conservatory with white washed walls that contrast with the exterior’s Shou Sugi Ban finish

Image: Conservatory interior with white washed walls that contrast with the exterior’s Shou Sugi Ban finish, Ståle Eriksen

My clients, a family who live in a Grade II listed house in Islington, London, wanted to replace a steel and glass conservatory at the rear of their home that was leaking and damp. Its replacement needed to complement the garden, which is relatively big for the area. I proposed a timber structure because it is a material that is both contemporary and ancient, so the new build wouldn’t overpower or be too subservient to the house.

Tell us about the roof?

Roof modelled in 3D and cut by Computer Numerical Control (CNC) router

Image: The roof was modelled in 3D and cut by Computer Numerical Control (CNC) router, Ståle Eriksen

A lot of inspiration came from the shortcomings of the original conservatory. There was a height limitation in place, determined by the boundary wall, so the roof had to have a shallow pitch and this is where drainage issues had arisen, which contributed to the structure leaking. The solution was a timber diagrid design with faceted double glazing, which created several small but steep pitches, allowing the water to be directed to a gutter at the junction between the house and the conservatory. Seen from the garden, the front of the conservatory is streamlined and free from visible gutters and drainpipes.

Read more: How to upgrade the exterior of your home

How does the roof design impact the interior?

It gives a sense of space and light and, although fully glazed, it is warm and well insulated. The deep struts of the roof structure cast interesting shadows around the interior when the sun hits it in the afternoon. The new conservatory is the family’s favourite part of the house and where they spend most of their time.

Which timber did you use and why?

 Exterior of timber frame conservatory with faceted, glazed roof by Taro Tsuruta

Image: The boundary wall, leads off a sharp angle, which influenced the diagrid form of the roof, Ståle Eriksen

Mostly Accoya, which is a softwood that goes through acetylation to make it more stable and rot resistant. The exterior timber has been Shou Sugi Ban treated to give a dark, charred finish, while the interior has been white washed to reduce the wood’s green hue, and the panelling and cabinets are made of ash.

Read more: A sculptural, charred timber work cabin inspired by Wabi Sabi


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