By: Carol A. Sigmond
Certain building materials, such as wood, have been in use since humans first built huts and lean-tos. In more recent years, condominium and cooperative boards have been dealing with a variety of building facade issues, including issues involving insulation and wood windows. Concrete walkways have also required regular maintenance and repair, including the need to periodically rip them up and reinstall them. Today, in the twenty-first century, we have additional options, which may prove to be gentler both to the environment and to building finances.
Timber has long been used as a building material. However, except where the wood has petrified, it doesn’t have a long life and requires constant maintenance. But, now there is a new material known as mass timber. Mass timber is solid wood that has been panelized and laminated to increase strength and durability.
Mass timber can be assembled in a variety of ways, such as beams made of pieces glued together or cross laminated materials made from overlapping panels. The material may also be fitted with dowels for linking panels together. Additionally, these materials are more fire resistant than traditional timber, as the outer layers char and insulate the rest of the wood, allowing it to maintain its structural integrity.
This material is environmentally friendly and its manufacture and use are increasing in the United States. The strand version appears suitable for windows that aren’t likely to require as much maintenance and that should have a longer life span. The color and finish options for these materials are endless, so achieving an acceptable look should be feasible.
Self-healing cement involves embedding small water-permeable capsules in wet concrete. The capsules contain dry fungus with nutrients in suspended animation. If the concrete later cracks and the water penetrates, the fungus will activate and form crystalline calcium carbonate, much like a limestone or marble material. The calcium carbonate protects the interior of the concrete structure, and, most importantly, the structural steel within. Concrete can last more than 100 years and will be free from cracks and fissures. Self-healing cement may increase the life span of concrete walkways, retaining walls, decks, and steps.
Air Cleaning Brick
Air cleaning brick is a system first demonstrated at the Italy Pavilion at the Milan 2015 Expo. The purpose of air cleaning bricks is to improve indoor air quality passively—the bricks themselves are a double layer that let air pass through the first layer to a chamber with a cyclone filtration system. The heavy particles drop to the ground for later removal. The cleaned air passes through the second layer of brick to a layer of insulation. This is a building-wide system and isn’t really intended for maintenance, but if you are considering a total reskin of a building, it might be an option for consideration—the system is relatively inexpensive and removes about one-third of fine particulates and all coarse particulates.
Heat Shedding Facade
Another reskinning option is a passive cooling clay composite. High-rise buildings generate heat, so cooling is a common issue. Facades made with a synthetic clay and mixed with hydrogel shed heat and the heat contacts the hydrogel. The heat is then transferred to the hydrogel and becomes water drops that evaporate. This material has reduced cooling requirements by 25 percent.
Recycled Insulation Materials
Finally, there are insulations made from recycled trash, particularly scrap metal, cardboard, and recycled plastics. Recycled cardboard insulation is out-performing certain traditional high-quality cellulose insulations, and recycled plastic bottles make excellent, durable carpeting suitable for institutional use.
As you consider major maintenance projects for your building, ask your design professionals to advise you on the cost, durability and other features, both positive and negative, of using new materials, particularly environmentally friendly materials. Also, ask about the maintenance implications of these materials.