The Green House on Cambridge Heath Adds Mass Timber Addition to Rehab of Existing Building

©. Waugh Thistleton Architects

Waugh Thistleton Architects demonstrate how we should be building for a low carbon future.

In a recent post discussing the World Green Building Council's recent report, Bringing Embodied Carbon Upfront, I noted that it's not just important to reduce our operating energy and our upfront carbon emissions, but that we had to rething what we build and how much we build.

Development stages

© World Green Building CouncilWe had to "question the need to use materials at all, considering alternative strategies for delivering the desired function, such as increasing utilization of existing assets through renovation or reuse." We had to "apply design approaches that minimize the quantity of new material required to deliver the desired function." Finally, we had to "prioritize materials which are low or zero carbon, responsibly sourced, and which have low lifecycle impact in other areas."

Then a Waugh Thistleton tweet pointed to a video of a recent project of theirs, the Green House, that is just the perfect demonstration of these principles in action.

blowup of building

© Waugh Thistleton Architects

They could have demolished the derelict concrete office building and replaced it, and some might have even said that this would be fine if they replaced it with a wood structure. But building less, maximizing use of existing assets, has a lower carbon footprint and is what we should do first, instead of sending all that concrete to the dump.

Detail of construction exterior

© Tim Crocker

So instead, they recycle and refurbish the existing concrete structure, "and taking advantage of its existing thermal mass, we will use the low-weight, high-quality structural properties of CLT [Cross-Laminated Timber] construction to significantly extend the internal space, increasing it to 50,000 sq ft." The CLT is made by Stora Enso in Austria, who claim:

Interior mass timber

© Tim Crocker

Massive wood – a renewable resource – also helps you deliver sustainable development. Wood stores carbon. When wooden building elements are recycled or reused, the carbon storage is also extended. And because Stora Enso Wood Products’ wood supply chains are covered by wood traceability systems which are certified according to PEFCTM or FSC® Chain of Custody system or both, you can rest assured your timber comes from a forest managed to the highest environmental and social standards.

addition to front facade

© Waugh Thistleton Architects

They have added a bit to the front facade, "providing a new dynamic frontage onto Cambridge Heath Road, the extension to the front of the building will facilitate the passive regulation of noise, heating, sunlight and ventilation."

Ventilation of the building is all natural?

© Waugh Thistleton Architects

This is again an example of Sufficiency, of doing as little as possible, adding as little as possible. Or as the WGBC noted, to "apply design approaches that minimise the quantity of new material required to deliver the desired function." Conceptually I love the idea of natural ventilation, but wonder, with the air quality in London and the recent hot summers, whether it actually can work anymore. But it is the right thing to do.

front addition

© Addition to front facade/ Jim Stephenson

The entire building appears to be about doing the right thing, but that also seems to be the mandate of the owner, Ethical Property, "one of the largest social businesses in the UK, owning and/or managing a total of 23 Centres across England, Scotland and Wales, and providing office, meeting, event and retail space to over 1000 organisations each year... Each of our Centres are managed with the environment in mind and our financial, environmental and social performance is externally audited on an annual basis."

stair and timber is all left exposed

© Jim Stephenson

The new construction added behind the existing building has "a main atrium at its centre to enhance its networking community." I love how the CLT is all exposed and the way the stair is detailed.

stair in atrium

© Jim Stephenson

Everything is left visible, including the wiring troughs that are usually hidden above a ceiling; it is all about just using less stuff. There is nothing here that doesn't serve a purpose. It's not tarted up or decorated, it is just doing its job.

office space view to windows

© View to windows/ Jim Stephenson

There is so much to love about this building, designed for an ethical client, following the principles of reusing what you can, building with low-carbon materials, and adding the minimum of new stuff. It's not grand, but it is a model of what a building should be today.

looking to the CIty

© Lisa Payne/ Waugh Thistleton Architects

You can look out the window from the Green House and admire the Gherkin and the Cheesegrater and the Scalpel and all the fancy new buildings under construction in the City, but the real future of sustainable design is happening on Cambridge Heath.

Interesting connection detail

© Interesting connection detail/ Tim Crocker