If you're planning on repairing or replacing your home's siding, you've probably already thought about the cost, labor, and maintenance. But have you also considered where the raw materials will come from, or whether they were responsibly harvested or mined? What about once the siding reaches the end of its life, will you be able to reuse or recycle the materials? Because a home's exterior can reflect as much about the homeowner's green lifestyle as the interior, we've put together some of the environmental pros and cons of the siding options currently available.
The first way to make your siding project more eco-friendly is to carefully remove the existing materials. Fiber-cement siding, aluminum, stone, brick, or wood may all be reused in other homes and kept out of landfills if gently dismantled in a process known as soft demo. You can either deconstruct your house's siding and deliver the materials to a salvage yard yourself, or hire a soft demo contractor to dismantle, dig up, and sell the materials for you. To find a soft demo contractor or a salvage organization where materials may be donated, visit the web pages of RecycleWorks and Green Demolitions.
Hardboard, plywood, and oriented strand board (OSB) are made from wood chips or wood veneers bound with urea or phenol formaldehyde resin. Urea formaldehyde has been classified as a possible carcinogen and presents an off-gassing potential, though phenol formaldehyde off-gases much less. In addition, engineered wood is cheaper than solid wood siding, but has a questionable track record due to poor moisture resistance and dimensional instability. While OSB and hardboard use smaller, lower-grade trees than solid wood siding or plywood, and therefore present an environmental advantage, all engineered wood requires regular maintenance and repainting.
- The Collins Companies manufactures a high-quality, Forest Stewardship Council (FSC)-certified, 100 percent post-industrial engineered wood product called TruWood Siding. Also, look for formaldehyde-free engineered wood.
- Bark siding is less cost-efficient, but it's superior to engineered, composite wood siding because it's renewable and biodegradable; contains no chemicals, preservatives, or borax; is resistant to weather without toxic sealants; and can last over 50 years without paint, stain, or other chemical protection. In addition, more and more manufacturers, such as Bark House and Parton Bark, are offering Sustainable Forestry Initiative ( SFI )-certified products.
It may be inexpensive, durable, require little to no maintenance, and sometimes installed over existing siding, but it can also be harmful to human health and the environment. The energy-intensive process required to produce vinyl, or polyvinylchloride (PVC), creates a carcinogen known as dioxin, as well as a number of other highly toxic byproducts. When the dioxins are released into the environment either through manufacturing or incineration, they are consumed by fish and animals, which are then eaten by human beings. In addition to cancer, dioxins have been linked to hormonal interference and neurodevelopmental problems in children.
Eco-friendlier Alternative: Cement Fiberboard is manufactured using cement, silica sand, and wood fibers, which are noncombustible and do not release toxins when installed. Not only is fiber cement siding an eco-friendly alternative to vinyl, but because it is grained to look like real wood, it is also a favorable choice to engineered, composite, or actual wood. The leading fiber cement siding manufacturer, James Hardie, also helps support regional economy and reduces the environmental impacts of material transport by offering more than 10 US facilities.
Brick, Rock, and Stone Siding
Clay for brick making is excavated by digging and trenching, while rock and stone are acquired by using explosives to demolish hillsides, forests, and plains. The harvesting methods for these raw materials also require the use of diesel-powered machinery and equipment. In addition, quarrying rock and stone is particularly harmful to the earth's surface, as it causes permanent scarring to the landscape, destructs naturally existing features, and potentially ruins floral and faunal habitats. While clay, rock, and stone are abundant resources, they are by no means renewable.
- To lessen the impacts of masonry, look for salvaged stone or brick.
- GenStone siding products do not use any kind of stone, cement, or mortar in their manufacturing process. Instead, they compress a combination of polyurethane and color oxides into cast stone, rock, or brick moulds. The siding panels are inert and nontoxic, as well as distinctive, durable, and waterproof.
It may have a high recycled content and be recyclable at the end of its life, but aluminum siding requires a lot of energy to produce. It can also be easily dented and chipped; it provides virtually no insulation; and it conducts electricity.
- EcoClad is an environmentally-friendly, sustainable product composed of bamboo fibers, post-consumer recycled paper, and recycled wood fiber. It's as durable as metal, brick, and stucco, but it doesn't support bacteria or fungus growth. EcoClad is also free of Volatile Organic Compounds (VOCs) and benzene, and the manufacturer offers seven different credits within US Green Building Council's Leadership in Energy and Environmental Design (LEED) building standards.