The Good and Bad of Sustainable Building Materials
EcoLiving June 2010
There are no magic solutions when doing home renos. Even environmentally preferred solutions have a cost. The key to making the right choice in home improvement materials is spending the time to do a bit of research, says Helen Goodland, executive director of the Light House Sustainable Building Centre in Vancouver. “[It’s not about] making snap decisions based on seeing a trendy magazine.”
Want to build with wood, without destroying natural forests? Find out if wood is from a sustainable source by looking for certification by a reputable agency like the Forest Stewardship Council (FSC) or the Canadian Standards Association (CSA). Be aware that even with certified wood, there are still downsides: For one, the supply doesn’t yet meet demand, which means you may pay a premium for wood that clears your conscience. Also, these sustainable forests are young, so their lumber is small-sized. And even certified wood still has an environmental price. But all things considered, FSC or CSA certification does indicate a better option than uncertified options.
You can also protect forests by salvaging wood from older structures. A dismantled trestle bridge or the hardwood from a closed-down factory can become the makings of a stunning living-room floor. Unfortunately, it’s harder to come by because newer construction is less salvageable, says Goodland. “We’re not designing for disassembly. We’re using tons of glues and adhesives, which are mostly toxic, just because they are quick and easy.”
There are now ways to use renewable plants in place of wood and plastics. Bamboo can be installed for flooring, bales of straw or hemp for walls, and soy or cotton for insulation. “Bamboo performs the same as hardwood and is cheaper,” says Cooper Grant, a green builder in Woodbridge, Ont. “And it grows rapidly, so when you harvest bamboo, you’re not cutting down a tree that’s going to take years to grow back.” But he also points out that there are still environmental concerns. Bamboo is not grown locally, so transport is an issue. And make sure to look for a product made without formaldehyde.
Straw can be produced right here in Canada and is an excellent insulating material. Plus it’s easy to install for walls, and when it’s covered in plaster, it creates a distinct look that appeals to some homeowners. But it’s still experimental. “I love straw,” says Grant. “But the plaster cracks, and you start getting moisture. It’s not a proven system, especially in a cold climate.” Other plant applications are more promising. Grant says he always recommends a soy-based spray foam for insulating because its cost is comparable to plastic foam and it works just as well. “And cotton performs very well, with no off-gassing,” he adds.
Goods instead of garbage
No question there are advantages to using recycled paper in countertops, or recycled plastic in patio tiles. You’re saving these materials from going to the landfill. And if a composite deck never requires staining and won’t need replacing for years, it’s convenient for the homeowner and healthier for the environment. But many of these composites are so new that they haven’t stood the test of time. Ask a pro who has worked with the composite, and ask to be put in touch with homeowners who have had a product installed.
Another key question, says Goodland, is whether the ingredients that make up the composite can ever be separated out again. “At the end of its life, how do you dispose of that? Will it decompose very slowly and poisonously?” Choose items that contain biodegradable components like paper and plant fibres instead of plastics. Or look for products that will get reused by the manufacturer at the end of its lifecycle, such as some carpet tiles.
Recycled paint is an inexpensive environmental option. However, the colour choices may be limited, and the paint may contain VOCs (volatile organic compounds). Many paint manufacturers now offer greener options, but read the label carefully: some contain less than five grams of VOCs per litre (“zero VOCs”) while others, marked “low” in VOCs, may contain more. These low-odour paints may be better for your health, but performance varies. You can find product reviews online (see links 1, 2 and 3).
With some legwork, you can find some interesting paint alternatives. Milk paint, made from casein (a milk protein), can be purchased from some antique or eco-product suppliers, who can also provide instructions on how to apply it. Or you can make clay paint yourself using recipes and directions found online. “Milk paints are applied like normal paints, but with clay it depends; some clay paint is trowelled on like a natural plaster,” says Goodland.
Durability can be a downside of the natural options. “Milk paint might work for a staircase or a living room, but it may not work for a kitchen or bathroom, or outside,” says Goodland.