What is Low-Carbon Concrete?

The active ingredient in concrete is cement, and concrete’s ubiquitous usage makes cement the most widely used industrial commodity today. The world consumes about half a ton of cement per person per year. But alongside its positive benefits as a construction material, cement also puts a major strain on the environment. Cement production currently accounts for 3% of world energy consumption and roughly 8% of global greenhouse gas emissions. Reducing emissions from the cement sector is critical to meeting the United Nation’s goal of limiting global warming to 1.5°C, but the sector has proven inherently challenging to decarbonize. This challenge is prompting a major drive to develop technological solutions that can address these processing emissions, including significant upticks in both investments and startup activity in low-carbon cement.

What is a Passive House?

‘Passive House’ is a design standard that achieves thermal comfort with minimal heating and cooling by using insulation, airtightness, appropriate window and door design, ventilation systems with heat recovery, and elimination of thermal bridges. Originally developed in Germany in the 1990s, Passive House principles are now being used throughout the world. Passive House standards are performance-based: they set performance targets to be met but do not dictate specific materials or products. The Passive House Institute administers a certification scheme that allows a building to be called a Certified Passive House once it has met certain performance standards.

12 Sustainable Building Materials

A sustainable (a.k.a. eco-friendly) building material is one that minimizes its impact on the environment – whether in its production, use, or disposal – and that can be readily recycled. Building with sustainable materials reduces the amount of carbon involved in the growth, production, and/or manufacturing of the material, thus diminishing the size of the carbon footprint associated with that material. Here we discuss some candidates among the current generation of eco-friendly building materials.

Ascent Tower the World’s Tallest Timber Building

CTBUH certifies Ascent as World’s Tallest Mass Timber Building
The Council on Tall Buildings and Urban Habitat (CTBUH) has officially declared the recently-opened Ascent tower by Korb + Associates Architects the world’s tallest timber-concrete hybrid building. The 25-story, 86.6-meter (284-foot) structure in Milwaukee takes the distinguished title in two of the mass timber categories: It is both the tallest timber building overall and the tallest concrete-timber hybrid building.

The previous world’s tallest timber building was Mjøstårnet in Brumunddal, Norway, certified by CTBUH in 2019, which stands at roughly 280 feet. Previously holding the record of tallest concrete-timber hybrid building was the approximately 276-foot HoHo building in Vienna, Austria.

The building features 259 luxury apartments, retail space, an elevated pool with operable window walls, and a sky-deck.

In May of 2019, Ascent was named a recipient of a U.S. Department of Agriculture grant awarded through the Forest Service’s Wood Innovations Grant program. The federal grant assisted with the testing needed to prove mass timber’s ability to perform as well as traditional building materials like concrete and steel to meet U.S. building codes.

Plans for the project were unveiled in 2018.While the initial design included 21 floors,updates and subsequent approvals brought the total to 25 floors in March of 2020.

The project had been presented at the 2018 international CTBUH conference in Dubai, the 2019 international CTBUH conference in Chicago, and the 2019 International Mass Timber conference in Portland.

The Ascent development was constructed using a digital twin model, allowing for materials, such as beams, columns, and panels, to arrive on site ready to use with holes pre-drilled to within 1/16-inch accuracy. According to CTBUH, it is estimated that using mass timber for the project decreased construction time by approximately 25 percent compared to a conventional, similarly-sized concrete building.

Straw-bale Construction

Straw-bale construction is a building method that uses bales of straw (commonly wheat, rice, rye and oats straw) as structural elements, building insulation, or both. This construction method is commonly used in natural building construction projects. Research has shown that straw-bale construction is a sustainable method of building, from the standpoint of both materials and energy needed for heating and cooling. Advantages of straw-bale construction over conventional building systems include the renewable nature of straw, cost, easy availability, naturally fire-retardant and high insulation value.

Building Responses to Heat Events

Climate-Proofing Buildings Against Excessive Heat
There are several options to implement climate-proofing of buildings with respect to excessively high temperatures. Such options relate to building design including the use of IT technologies to optimize thermal comfort and those involving building envelopes, including roof, wall, doors, windows and solar control glazing enhancements.

Mass Timber And Taller Wood Construction

What is Mass Timber Construction?
Mass timber construction, in contrast to light-frame wood construction, is built using a category of engineered wood products typically made of large, solid wood panels, columns or beams often manufactured off-site for load-bearing wall, floor, and roof construction. Mass timber is engineered for high strength ratings like concrete and steel but are significantly lighter in weight. Mass timber products are thick, compressed layers of wood, creating strong, structural load-bearing elements that can be constructed into panelized components. They are typically formed through lamination, fasteners, or adhesives. Mass timber can complement light-frame and hybrid options and is an environmentally friendly substitute for carbon intensive materials and building systems.

The World’s Tallest Wood Building

Mjøstårnet in Brumunddal, Norway, has been verified as the world’s tallest timber building by the Council on Tall Buildings and Urban Habitat. The 280-foot-high tower was built using cross-laminated timber (CLT), a pioneering material that allows architects to build tall buildings from sustainable wood.

What Is Sustainable Architecture?

Sustainable architecture is a general term that refers to buildings that are designed to limit humanity’s impact on the environment. An eco-friendly approach to modern day building encompasses every aspect of the planning and construction process. This includes the choice of building materials; the design and implementation of heating, cooling, plumbing, waste, and ventilation systems; and the integration of the built environment into the natural landscape.

New Ultra-white Paint Reflects to Cool Buildings Even in Bright Sunlight

Scientists have developed a white paint that cools below the temperature of its ambient surroundings even under direct sunlight. Their research, published in Cell Reports Physical Science journal, demonstrates a radiative cooling technology that could be used in commercial paints, could be less expensive to manufacture, and that passively reflects 95.5% of sunlight that reaches its surface back into outer space. In contrast, commercial “heat rejecting paints” currently on the market only reflect 80%-90% of solar irradiation and cannot achieve below-ambient temperatures.