The materials and measures empowering energy efficiency in buildings
Published on 25.06.2021
Particularly in small-scale construction, materials such as rammed earth, wood, and even straw are used as natural alternatives to synthetically produced options. While organic, these materials are highly resistant, durable, and provide excellent insulation, helping a building achieve optimal energy efficiency.
Wood, even for large-scale structures and skyscrapers1, continues to be explored as a material with which to create innovative and sustainable buildings. In addition to its naturally endowed energy efficiency, wood improves a building’s sustainability on many levels including shorter construction timescales and a reduction in the overall weight of the structure.
Mjøstårnet in Norway, the world’s tallest wooden building
Recycled or mix-and-match materials
Large-scale structures found in urban centers increasingly rely on a mix of recycled or hybrid materials to achieve greater energy efficiency. These include:
- Recycled steel. It ensures energy efficiency due to its high durability and rigidity and uses less energy than conventional steel while emitting less CO2.
- Wood, either manipulated or mixed with other properties. Cross-laminated (CLT) wood is made from gluing together layers of solid-sawn lumber. Studies show using CLT reduces energy consumption by 15%2. Other highly sustainable, energy-efficient composites can be made from a 50-50 mix of plastic wastes and wood fibers.
- Structural Insulated Panels (SIPs). Consisting of a layer of foam insulation between harder layers of cement or wood, SIPs can cut indoor climate control costs by 50%3.
No one-size-fits-all solution
Just as important as the materials: how are the materials adapted to achieve the greatest energy efficiency possible? Mega cities could take inspiration from Hong Kong4. The city has set a goal to become climate neutral by 2050, and it is making inroads to energy efficiency by addressing specific elements of skyscrapers. Among other measures, the city aims to:
- Make the most of facades by lining them with high-reflective materials to reduce the energy needed for indoor climate control. Alternatively, use customized building integrated photovoltaic (BIPV) panels.
- Triple wall exterior systems to enhance energy performance.
- Orientate the positioning of towers to reduce the sun’s effect.
- Top up with “cool roofs.” In addition to painting roofs white, builders can combine rooftop gardens and solar panels, which increases solar panel efficiency. This also dramatically decreases the heat-island effect in high-density areas.
“Cool roofs” reduce a building’s energy output
Energy efficiency in buildings is ultimately driven by the organizations that occupy them. Two UN initiatives help guide companies to achieve climate neutrality. “Race to Zero”5 aims to gain support from all non-state actors for a zero-carbon recovery. “Business Ambitions for 1.5°C”6 is a call to action for companies to ensure their emissions will match with the 1.5°C goal.
In addition to expanding its green vehicle fleet, TK Elevator sees many opportunities to achieve these goals. All facilities and factories will strive for greater energy efficiency through the use of sustainable materials, circular economy principle, and more renewables. Companies can push to make energy efficiency in buildings the norm rather than the exception. In doing so, they pave the way for others.
Has the wooden skyscraper revolution finally arrived?, by Oscar Holland via cnn.com/style
Energy retrofit analysis of cross-laminated timber residential buildings in Seoul, Korea: Insights from a case study of packages, by Hyun MiCho et al. via sciencedirect.com
The Most Energy-Efficient Materials From Which to Build a House, by n.u. via hirecentres.com
The city of sustainable skyscrapers, by Matthew Keegan via bbc.com
Race To Zero Campaign, by n.u. via unfccc.int
Join the Campaign for Our Only Future, by María Fernanda Espinosa Garcés et al. via unglobalcompact.org
Mjøstårnet in Norway, the world’s tallest wooden building, video by Woodify, taken from youtube.com