The international community has caught onto the need to halt global warming and promote a low-carbon economy. The European Union has established a binding target for 2030 to cut greenhouse effect gases by 40% in comparison with 1990 levels. And by 80% in 2050.
The building industry is one of the key action levers in order to make these goals a reality. Within the EU, the sector generates 35% of all greenhouse gases that cause climate change. In this sense, Directive 2010/31/EU on the energy performance of buildings (responsible for 40% of all power consumption) stipulates that as of 31st December 2020, all new constructions must be ‘nearly zero-energy’.
The Passivhaus standard has raised building energy savings to new heights by aiming to reduce or eliminate heating or cooling requirements in order to guarantee interior thermal comfort. It sets out five key principles in the building process: outstanding levels of insulation for outer walls and roofs; thermal bridge-free designs; airtight barrier layers; a mechanical ventilation system with heat recovery; and high performance windows and doors. In order to be eligible for Passivhaus certification, buildings must deliver ambitious results in terms of power requirements and airtightness.
Passivhaus wooden house built by House Habitat in Castelldefels (Barcelona)
Why use wood for Passivhaus buildings?
All House Habitat’s building projects comply fully with Passivhaus criteria. Furthermore, we use natural and sustainable materials that respect people’s health and in this sense, wood is a key structural element due to its outstanding insulation properties.
A recent study revealed that if all the buildings in the city of Barcelona alone complied with Passivhaus criteria, CO2 emissions would be reduced by 1,022,349 tons, equivalent to the amount absorbed by no fewer than 100,000 trees.
The use of wood in construction would help to reduce pollution levels even further.
The use of wood sourced from sustainably managed forests, based on replanting principles, contributes to guaranteeing the survival of our planet’s major CO2 sinks. Young trees, planted for their later use in construction, remove carbon from the atmosphere as they grow, achieving higher rates of efficiency in comparison with more mature trees.
In sharp contrast, cement production is responsible for 6% of the world’s carbon emissions, whilst steel production – half of which is used in the building industry – accounts for 8%. During the process of transforming raw elements into building materials, wood produces the lowest levels of pollution attributable to CO2 emissions of all the most common materials. For instance, producing a laminated wood beam requires just a sixth of the energy needed to manufacture a steel beam with a comparable resistance performance.
In short, adopting the Passivhaus energy efficiency standard and using wood in buildings are two solutions that the construction industry can deliver in response to the urgent need to halt climate change. Two trends that complement each other to perfection and are also experiencing a sharp hike on an international scale.
