25.06.2021

The materials and measures empowering energy efficiency in buildings

What can cities, companies, and contractors do to create buildings that are climate neutral? Often the answer begins with energy-efficient building materials. We look at the materials – from the traditional to innovative – and how they are used to achieve greater energy efficiency.

Whether small-scale or skyscraper, buildings account for about 40% of all energy consumed. Especially in urban areas with high-density populations, creating sustainable, energy-efficient buildings is paramount to achieving climate-neutral standards. Increasingly, the use of different building materials is being explored to boost energy efficiency and cut a building’s emissions. From natural or recycled to hybrid and composite, options abound. We take a closer look at the materials and some other building measures shaping energy efficiency in construction today.

Go natural

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.

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.
Unilever House, Hamburg, Germany
Bosco_Verticale_Milano
Amazon_Spheres

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

Corporate responsibility

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.

TK Elevator has joined both initiatives with their carbon targets: a carbon footprint reduction of 25 percent by 2030 and a 50 percent reduction by 2040.

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.

Sources

  1. Has the wooden skyscraper revolution finally arrived?, by Oscar Holland via cnn.com/style

  2. 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

  3. The Most Energy-Efficient Materials From Which to Build a House, by n.u. via hirecentres.com

  4. The city of sustainable skyscrapers, by Matthew Keegan via bbc.com

  5. Race To Zero Campaign, by n.u. via unfccc.int

  6. Join the Campaign for Our Only Future, by María Fernanda Espinosa Garcés et al. via unglobalcompact.org

Image Credits

Mjøstårnet in Norway, the world’s tallest wooden building, video by Woodify, taken from youtube.com
“Cool roofs” reduce a building’s energy output, image by AleSpa, taken from commons.wikimedia.org
Unilever House, Hamburg, Germany, image by ChristianSchd, taken from commons.wikimedia.org
Bosco Verticale, Milano, Italy, image by Thomas Ledl, taken from commons.wikimedia.org
Amazon Spheres, Seattle, USA, image by Joe Mable, taken from commons.wikimedia.org