Circular Economy in Interior Design: Building to Disassemble
Alessandro Nicotra
Sustainability
In short
— The construction sector is Switzerland's largest consumer of materials. Building on existing structures and reuse save a lot of embodied energy.
— Monomaterially joined components can be detached, separated and reused during renovations.
— The most sustainable piece of furniture is the one that already exists. Those who inventory existing assets can intentionally incorporate them into their plans.
An interior fit-out often has a shorter lifespan than the building it is housed in. Tenants change, teams grow, ways of working evolve. Anyone building today should therefore already be thinking about the next renovation: about components that can be dismantled, materials that can be separated, and furniture that can move on.
The most sustainable piece of furniture is the one that already exists.
Why is interior fit-out important for the circular economy?
Because construction in Switzerland moves enormous amounts of material. According to the FOEN, the construction sector processes around 62 million tonnes of material each year. In addition, there are 16 to 18 million tonnes of deconstruction material per year, more than 5 million tonnes of which are not yet part of any circular flow (FOEN, Circular Economy). In the Canton of Zurich, more than two-thirds of all waste is construction waste (AWEL).
Building materials account for around 10 percent of Switzerland's greenhouse gas footprint, and the construction of buildings is also expected to reach net zero by 2050 at the latest (KBOB). Interior fit-outs are renovated more frequently than the building shell. That makes it a lever that can be repositioned with every renovation.
What does mono-material construction mean?
Building with mono-materials means joining components in such a way that they can be dismantled again and separated by material. Screwed instead of glued, plugged instead of foamed, separate layers instead of composite materials. The SIA states that elements must be designed and joined so that they can be easily disassembled, and that a clear separation of the load-bearing structure, building services, and fit-out extends the service life.
This is visible at the Zwhatt site office in Regensdorf: the central scaffolding is assembled using unmixed, separable connections, can be completely dismantled, and the steel can be reclaimed. In Lounge Z, we go even further. The furniture made of rammed earth bricks, plywood, and nylon straps uses no glue, nails, or toxic substances. Untie the straps, and you are left with bricks, panels, and straps once again—ready for the next configuration.
Mono-material assembled scaffolding in the Zwhatt site office
How much difference does reuse make?
A lot, if planned early. For building K.118 in Winterthur, which consists predominantly of reused building components, embodied greenhouse gas emissions were reduced by around 60 percent compared to a comparable new build (SFOE). At the Mööslistrasse kindergarten in Zurich, building components, furniture, and equipment were reused, resulting in 30 percent lower embodied emissions (EnergieSchweiz). At the same time, the guideline notes that reuse cannot cover everything. This makes it all the more important to preserve existing buildings first.
At the new Bern University of Applied Sciences campus in Biel, we recorded the inventory from nine locations and planned it into the new offices. Around nine out of ten pieces of furniture come from the existing stock. New items are only added where new ways of working require new furniture.
How do you measure the impact?
With an assessment that runs right from the start. In Workplace Intelligence, we decide for each inventory item whether it stays, moves on, or is replaced, and report the avoided embodied emissions. In addition, there are operational emissions, floor space before and after, and the question of when the fit-out emissions will pay off. Calculations and assumptions remain transparently disclosed. Upon project completion, you will receive the figures for your sustainability report. Find out more on our Sustainability page.
What are the benefits for the company?
Lower procurement costs and reliable figures for the sustainability report. Every piece of furniture that is reused does not have to be bought new. At the BFH Campus Biel, around nine out of ten pieces of furniture come from the existing inventory; new purchases are only made for what new ways of working require.
Mono-material, demountable fixtures pay off a second time during the next renovation: they can be disassembled instead of being torn down and disposed of. And because the avoided emissions are documented, they flow directly into reporting without the need for an additional study.
Zwhatt Community Office, Regensdorf
Frequently Asked Questions
What is embodied energy?
The energy required for the manufacturing, transport, installation, and disposal of building materials. During a renovation, it mainly arises from new materials and furniture.
Is re-use more expensive than buying new?
Not necessarily. Reused furniture saves procurement costs. Expenses are incurred for recording, refurbishment, and planning. When planned early, it often pays off.
Can you also build circularly in rented spaces?
Especially there. Tenant fit-outs are frequently renewed. Unmixed, demountable fixtures can be dismantled upon moving out and reused.
Which standards apply?
Embodied energy is balanced according to the SIA 2032 technical leaflet. The SIA 390/1 climate path defines target values including embodied emissions.
How do you start?
With an inventory: What is there, what is in good condition, what fits the new concept? A 3D scan and an inventory make this visible.
Sources
Raw materials, waste and circular economy: in brief, FOEN
Circular economy, FOEN
Construction waste, Canton of Zurich, AWEL
Embodied greenhouse gas emissions in building construction, KBOB, 2025
Planning and building in the circular economy, SIA, 2024
Building anew with old components, SFOE, 2025
Circular construction: A guide for investors and building owners, SwissEnergy, 2025
Good interior finishing considers the day it will have to be dismantled.
Contact
Listening is our first draft.
Every project begins with a conversation. Tell us what you have in mind: a new working environment, a restaurant, a space for the future. We bring an open mind, curiosity, and experience in strategy, interior design, and lighting. We'd love to meet at our studio on Gutstrasse in Zurich. Or wherever your project is coming to life.