Sustainable construction on auctioned land: What is possible?

An empty or partially developed property from a forced auction is more than just an affordable lot, it is a canvas for environmentally friendly architecture, sustainable energy concepts, and new business models like cooperatives or co-housing. Since you acquire the land below market price, the budget for sustainable innovations is greater than for a traditional purchase. This article explains how to build green, smart, and economically viable from the building permit to building operation.

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1 Potential Check: What does the property offer?

• Zoning Plan & Utilization Density: In many municipalities, the utilization coefficient can be increased by 10-20% in exchange for ecological benefits (solar obligation, timber construction quota).
• Soil Class & Geology: Clarify whether geothermal probes are possible or if low-tech soil heat collectors are a better fit.
• Solar Cadastre Switzerland: Optimize roof and facade areas before project planning.

“Sustainability starts with parcel analysis: understanding the underground saves expensive technology later.”

2 Five Future-Proof Building Concepts

Concept	Core Idea	Suitable For	CO₂ Reduction*
Wood Hybrid (CLT)	Mass timber structure + concrete cores made from recycled concrete	Multi-family housing up to 8 stories	▼ 65%
Straw Bale Passive House	Straw insulation in wooden frame, clay plaster inside	Single-family homes / Cluster houses	▼ 80%
Urban Mining Construction	Building components from deconstruction exchanges (windows, steel beams)	Warehouse conversions	▼ 70%
3D-Printed Clay	Robotic printing layer by layer	Garden pavilions, tiny houses	▼ 85%
Plus Energy Neighborhood	Building cluster with direct current microgrid	Large areas > 2,000 m²	▼ 100% (Net Zero)

*compared to conventional concrete-steel construction methods

3 Energy Concepts: From Low-Tech to High-Tech

3.1 Low-Tech First Strategy

• Super Insulation (λ ≤ 0.033) & Lucerne Windows = Heating energy demand < 10 kWh/m²a.
• Plan Microclimate: Deciduous trees on the south side, light facades → reduce summer overheating by ↓ 5 K.
• Thermal Mass: Rammed earth interior walls buffer daytime heat without active cooling.

3.2 High-Tech Booster

• Bidirectional PV Carports supply electric cars and serve as emergency power.
• A2W Heat Pump + Ice Storage has a 15% better COP than geothermal probes on difficult soils.
• DC Microgrid & Redox-Flow Battery for plus energy settlements.

4 Minimize Grey Energy: Urban Mining & Circularity

1. Building Component Network Switzerland, windows, doors, even complete load-bearing structures are reusable.
2. Recycled Concrete CEM III/B reduces cement CO₂ by 50%.
3. Screwpile Foundations instead of concrete slabs: deconstructable, minimal excavation.

5 Integrate Biodiversity & Water Management

• Sponge City Principle, permeable basins, retention roofs, green parking spaces.
• Species Protection Modules (bat boxes, swift nests) planned into the facade.
• Regenerative Agriculture on residual areas: Agri-PV & community gardens.

6 Law & Financing: How to Get Funding and Approval

6.1 Building Permit 2.0

Many cantons accept digital BIM submission processes. Include the following: daylight proof, CO₂ balance (SIA 2040), noise protection report. A clean dossier upload reduces the approval time by an average of 2 months.

6.2 Funding Mix 2025

• Federal Program Net Zero Pilot: Up to 40% grant for low CO₂ new buildings.
• Canton Bonuses for Timber Construction: e.g., BE: 60 CHF/m³ of Swiss wood used.
• ClimateBond Financing: Mortgage interest rate of 0.25% for compliance with Minergie-P-Eco.

7 Case Study: From Auction Field to Zero-Carbon Neighborhood

A 5,000 m² industrial area in Winterthur was auctioned in 2023. A cooperative consortium built 42 wood hybrid apartments + co-working spaces. Highlights: Plus energy, DC network, rooftop farm, mobility hub. Figures: Construction costs of 26 million CHF (-12% thanks to urban mining), funding of 5.8 million, return on equity: 7.5%, CO₂ amortization in 11 years.

8 Quick Checklist: Sustainable Building on Auction Land

1. Check zoning plan, soil report, solar potential.
2. Choose building concept (wood hybrid, straw, urban mining…).
3. Low-tech before high-tech: optimize envelope & passive design.
4. Calculate funding mix: federal + canton + private funds.
5. Create BIM model for approval & tendering.
6. Integrate CO₂ monitoring & LCA tool (OneClick LCA).
7. Plan deconstruction and recycling strategy simultaneously.

9 FAQ

Are wooden high-rise buildings permitted in fire class RF1?

Yes, as of VKF guidelines 2024, heights of up to 100 m are possible as long as fire protection encapsulation and sprinklers are proven.

Can I drill geothermal probes afterwards if there are contaminated land issues?

Only after remediation of contaminated sites or with horizontal collectors ≥ 1.5 m deep. Geological report is mandatory.

How does the bank view urban mining components?

With certified deconstruction proof (reuse certificate), most institutions accept the building value in full, and recommend a completion with construction guarantee obligation.

10 Conclusion: Auction + Sustainability = Double Profit

Auctioned properties offer flexibility, which is rarely found in traditional building land. If you use it for sustainable building, you combine price advantages with innovation bonuses: lower CO₂ balance, higher funding amounts, strong demand. In short: Those who build green on auction land today lay the foundation for tomorrow's returns and climate goals.