As the construction sector accelerates toward net-zero targets, addressing both embodied carbon (materials and construction) and operational carbon (building energy and indoor air quality) has become essential.
A recent study published in Buildings (2024) (https://doi.org/10.3390/buildings14051194) analyzed a 5-floor residential apartment project in Laajasalo, Helsinki, comparing a Cross-Laminated Timber (CLT) solid wood frame against a traditional reinforced concrete frame.
1. Frame Comparison: Concrete vs. Massive Wood (CLT)
The 50-year life-cycle analysis (A1–A5) reveals a stark difference in environmental and economic metrics:
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Embodied Carbon Footprint: The concrete frame generates 3,064,849 kg CO2e over 50 years, whereas the massive wooden CLT frame generates 830,223 kg CO2e — a 270% increase in carbon emissions when choosing concrete over timber.
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Carbon Handprint (Positive Climate Impacts): CLT acts as a long-term carbon sink, storing 4,542,907 kg CO2e compared to only 872,634 kg CO2e for the concrete solution—a 420% greater positive climate benefit for wood.
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Frame Investment Cost:
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Concrete frame self-cost: €8,150,378
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CLT frame self-cost: €9,114,500
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Additional regulatory costs for wood in Finland (sprinkler system and weather protection during construction): ~€1,840,000
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Cost Efficiency of Positive Climate Impact: Taking into account required sprinkler systems and weather protection, the cost of achieving positive climate effects with a concrete frame is 290% higher than with a massive wood frame.
2. Complementing Structural Reductions with Soletair Power Technology
While selecting a mass timber frame significantly reduces embodied carbon, active technological interventions like Soletair Power’s Direct Air Capture (DAC) and building-integrated CO2 capture solutions tackle operational emissions and indoor air quality.
Scenario: Investment in Soletair Power Technology
Soletair Power capture technology, achieving an operational reduction of 10 kg CO2/m^2/a over a 50-year lifetime:
Impact across the Laajasalo Case Study (approx. 9,677 m^2 residential floor area)
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Total Operational CO2 Captured over 50 Years:
9,677 m^2 * 500 kgCO2/m^2 = 4,838,500 kgCO2 -
Abatement Cost per kg CO2 Captured:
(€800,000/ 4,838,500 kgCO2) = €0.165 kg CO2
3. Comparative Overview: 50-Year Climate & Economic Impact
| Parameter | Concrete Frame | Wooden CLT Frame | Concrete + Soletair Power | CLT + Soletair Power |
| Initial Frame / System Cost |
€8,150,378 |
€10,954,500 (incl. €1.84M sprinklers/weather protection)
|
€8,950,378 | €11,754,500 |
| Embodied Carbon Footprint (50a) |
3,064,849 kg CO2e
|
830,223 kg CO2e
|
3,064,849 kg CO2e
|
830,223 kg CO2e
|
| Carbon Handprint / Stored (50a) |
-872,634 kg CO2e
|
-4,542,907 kg CO2e
|
-872,634 kg CO2e
|
-4,542,907 kg CO_2e
|
| Operational CO2 Avoided/Captured (50a) | Baseline | Baseline | -4,838,500 kg CO2 | -4,838,500 kg CO2 |
| Net 50-Year Emissions Balance | +2,192,215 kgCO2e | -3,712,684 kgCO2e | -2,646,285 kg CO2e | -8,551,184 kg CO2e |
Strategic Takeaways for Real Estate Developers
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Concrete can be decarbonized operationally: Integrating technological solutions like Soletair Power’s DAC into concrete buildings turns a net carbon emitter (+2.19M kg CO2e) into a net carbon negative asset (-2.65M kg CO2e) over a 50-year lifecycle.
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CLT + DAC yields maximum carbon negativity: Combining a CLT solid wood frame with Soletair Power technology achieves an impressive -8.55 million kg CO2e net balance over 50 years.
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High Return on Sustainability Investment: At ~€0.165/kg CO2, operational capture technology offers an affordable long-term abatement strategy to meet stringent local building thresholds and corporate ESG goals.
