Low carbon can be low cost

Low carbon

Carver Haggard keep things simple for an award-winning retrofit.

The refurb and extension of 198CAL – an arts centre in South London – demonstrates that low-carbon solutions do not have to be expensive. TDUK members Carver Haggard picked up a RIBA

Isometric drawing of 198CAL. Key: 1=Gallery, 2=Kitchen, 3=Archive, 4=Office, 5=Community Workspace, 6=Studio, 7=Production Room, 8=WC, 9=Store All photographs © Francesco Russo

London award for their successful, economical transformation of the building. They tripled the floor area, largely by adding two further storeys to the single-storey building and its extension. All on a very modest budget.

“We often equate low carbon with high cost,” points out Toby Maclean, the project’s Structural Engineer. “This project turns that on its head. Unusually, the value engineering process – which so often leads not to lower quality and higher future costs – demonstrated that value and low-carbon can be comfortable partners.”

The scope of strengthening works was limited to the simple introduction of a single 80×80 new post under a cantilevered corner of the existing roof.

This meant a lightweight structure for the new storeys was imperative. An iterative costing exercise with the contractor proved a timber solution was cheaper than a steel equivalent.

“The design also demonstrated the versatility of traditional timber frame – stud and joist – design over engineered and mass timber options,” Maclean enthuses.

“Traditional timber framing uses less timber, and so is lighter and incurs lower upfront embodied carbon. Engineered timber was limited to glulam beams acting as mini-transfer beams to support the new loads off the existing structure.”

Read issue No 2 here