The UK’s greenest building will rise in Southern Manchester, with the six-storey Ev0 building set to become a prototype for the future net-zero design and construction not only across the UK but worldwide.
The net-zero building will utilise 100% renewable power in operation and use extensive mass timber and low-carbon concrete to drive reductions in embodied carbon – with timber beams and columns designed to be easily disassembled and reassembled in the future.
And whilst the developers acknowledge that the project’s initial design was slightly more expensive than a conventional build, “we’re pioneering something different,” according to Aisling McNulty, Bruntwood’s development director, who added that the costs would be more than offset by the 58% reduction in operational costs.
The push to build the UK’s most sustainable building comes as the UK construction industry has turned its attention to embodied carbon as the industry gets serious about Scope 3 emissions.
Last year, Wood Central reported that four of the UK’s largest contractors were using software that provided real-time reporting on emissions – which, for the first time, captured the embodied carbon from the production and transport of concrete, steel, and timber.
More recently, the UK government released its bold timber roadmap last year, with Rishi Sunak’s Conservative government turning to low-carbon materials to supercharge its push to net zero.
Wood Central understands that the £31M project, which will start construction later this year, has been designed to have just 516kg CO2e/m2 in upfront carbon emissions, besting the country’s 2020 design targets for upfront carbon by more than 14%.
According to Simona Peet, Ramboll’s structural engineer responsible for the project, combining mass timber in hybrid with low-carbon concrete is key to driving decarbonisation in new buildings, especially in the commercial sector.
“We are using glue laminated timber, or glulam, for the framing elements such as columns and beams. The cross-laminated timber panel elements will be used as a slab or in non-load bearing wall elements,” according to Ms Peet.
The vision for Ev0, according to Ms Peet, is to build a timber frame capable of capturing and storing carbon over its planned 50-year lifespan.
“A timber frame will lock carbon out of the atmosphere for this building’s lifespan and store about 4,000 tones of carbon. We’re talking about significant numbers here,” according to Ms Peet.
Reducing material consumption is in Ev0’s design DNA!
The building will limit the use of concrete in its substructure and core walls, with the project study, in the early stages, “looking at ground granulated blast furnace slag (or GGBS) as a reference material.”
“We have assumed 25% cement replacement across the whole project, which typically will reduce embodied carbon by 20% compared with 0% cement replacement.”
Simona Peet, Ramboll’s structural engineer responsible for the project.
According to Ramboll’s Martin Bissell, reducing materials was vital to reducing carbon consumption. Of the shape and height of the building, he says: “It’s more or less a cube, and that’s deliberate.”
“The idea is to make sure that the external facade and roof of the building are as small as possible relative to the floor plate to limit heat loss, heat gain and the amount of material used,” Mr Bissell said.
Additionally, he said the dimensions of the window openings in the facade maximise beneficial solar gain and minimise negative solar gain to almost zero, “meaning that the design aids in heating the spaces but prevents overheating.”
Design for disassembly principles was “enshrined” in the EvO’s design principles, with Mr Bissell telling the New Civil Engineer that connections between the timber beams and columns can be unbolted and unscrewed to allow for reuse.
For Ms Peet, parametric design was critical, allowing the design team to calculate load path analysis and the structure of the frame.
Parametric design is a method whereby features, such as building elements and engineering components, are shaped based on algorithmic processes rather than direct manipulation.
“It was also used to optimise the building’s cuboid form and orientation – the facade faces 15° north-northeast – and for embodied carbon and operational carbon calculations,” she said.
“On a building like Ev0, we needed to be able to examine different structural forms and grid core layouts quickly,” Ms Peet said.
“Our in-house tools use advanced techniques to automate the design earlier on in Riba Stage 1 [preparation and brief] and Stage 2 [concept design].”
“As a result, we could provide a detailed carbon footprint analysis that enables us to review many options with multiple variables in a short period of time and to optimise the number of structural elements and core layouts.”
Once operational, Bruntwood will publish the carbon performance data for the building to encourage transparency for ongoing benchmarking.
For Ms Peet, Ev0 will be invaluable in growing the pool of expertise on zero-carbon construction.
“We were challenged to deliver an exceptional environmental performance, but not just that, to accelerate the learning and development in the net zero field. The journey was as important as the destination on this project.”
