Green Building Materials Yankton SD
Rapid City, SD
Rapid City, SD
Choosing Green Building Products
There are hundreds of green building-material options available to homeowners today but how do you choose what to use in your home? The key is that you don't have to do everything. Pick and choose among the many options for the ones that best serve your interests.
There is no such thing as the right or wrong set of products. Some are more expensive than others. Some may not even be feasible for your project, given varying regional climates and code regulations. Certain aspects of building may have a greater impact than others on energy efficiency, the environment or your health. Focus on those aspects that are most important to you.
Fortunately, as we demonstrate below, there is an ever-growing list of green building products available from foundation to framing materials, plumbing to HVAC systems, decking products to landscaping systems. In addition to the descriptions below, we've made some recommendations, so you can decide on the right options for your home.
∗ Insulated concrete forms (ICFs). These lightweight, interlocking, rigid foam blocks or panels hold concrete in place during pouring and curing, and remain in place afterward to serve as thermal insulation for concrete foundations or above-grade walls. ICFs have higher thermal efficiencies than solid concrete foundations or walls and can reduce the total amount of concrete used, yielding material cost savings. Unlike untreated lumber, ICFs are not subject to rot and result in a higher-strength wall than standard cast-in-place concrete.
Recommendation: Use ICFs wherever an insulated foundation is desirable. Sizes and styles vary by manufacturer, but generally rebar is placed in hollow foam cores, and concrete (preferably containing slag or fly ash) is poured into the cores to create a load-bearing structure.
∗ Fly ash in concrete. Fly ash is a byproduct of coal-burning power plants. It is typically dumped into landfills, but it can be used as a substitute for a portion of the Portland cement in concrete. It is inexpensive and improves the performance of concrete by increasing its strength, reducing permeability and reducing corrosion of reinforced steel. Using fly ash also reduces the amount of water needed, adding to its environmental benefits.
Recommendation: Typically, up to 50 percent of cement can be replaced with fly ash in residential concrete mixes. However, high-volume fly ash mixes may require longer cure times than standard concrete.
∗ FSC-certified framing wood. Forest Stewardship Council (FSC) certification ensures that the forest from which the wood was harvested is managed in an environmentally, economically and socially responsible manner. FSC is the only lumber verification rating that maintains chain-of-custody certification throughout the cutting, milling and final delivery of products.
Recommendation: Use FSC-certified lumber where wood framing is required. Certified, solid framing and plywood are available from many home improvement retailers and lumberyards.
∗ Structural insulated panels (SIPs). An SIP consists of a rigid foam core sandwiched between two sheets of OSB (oriented strand board). Available in varying lengths and heights, these insulated wall and roof panels eliminate the need for traditional stick-frame construction.
SIPs are more energy efficient, provide better soundproofing than traditional frame construction, and are better at reducing air and moisture infiltration. In addition, they can be erected quickly. Although SIPs are initially more expensive than buying raw materials for conventional construction, the resulting savings in site labor, material waste and cleanup fees, as well as shorter construction timeframes, offset much, if not all, of the cost of the panels.
Recommendation: Use SIPs for structural exterior walls, roofs and floors in place of stick framing. Generally, you can modify almost any addition plan to build with SIPs.
∗ Recycled-content insulation. Nearly all building insulation contains some recycled content. Fiberglass insulation typically contains 30 percent recycled glass. Insulation products that use recycled cotton or newspaper contain up to 80 percent post-consumer recycled materials. Buying products with high post-consumer recycled content reduces landfill deposits and reliance on virgin raw materials.
Recommendation: Choose products that are at least 80 percent recycled material, and preferably those with a high level of post-consumer recycled materials. Post-consumer waste is recovered after a products useful life has ended. Install insulation to proper density per manufacturer instructions.
Bio-based insulation also has excellent sound-proofing properties, does not support mold growth, is resistant to pests, and reduces dust and allergens because there are no loose fibers. Although relatively new to the market, this insulation, which has an R-value of 3.7 to 4.0 per inch, has been hailed as one of the most environmentally friendly insulations available.
Recommendation: Use bio-based insulation in place of conventional types of insulation for an air-tight building envelope or if an occupant is allergy-prone.
∗ Low-e windows. Windows play a big role in the energy efficiency of homes. In the summer, they can allow unwanted heat into the house. In the winter, they can account for as much as 25 percent of the heat loss in newer homes and as much as 30 percent of heat loss in older homes.
Low-e (low-emittance) windows are coated with a microscopic layer of material that reduces heat loss and controls solar heat gain, keeping a home comfortable year-round. The cost premium of 10 to 15 percent for low-e glass typically pays for itself in a few years, since low-e glass coating increases glass R-value to 3, compared to R-1.9 for plain double-glazed windows.
Recommendation: When selecting windows, look for low-e models that have a National Fenestration Rating Council label listing, a U-value of 0.4 or less (to control heat transfer) and an SHGC (solar heat gain coefficient) of 0.4 or less in southern climes (to reduce air-conditioning bills) or 0.7 or greater in northern climes (to reduce heating bills).
∗ Compact fluorescent light (CFL) bulbs. Only 10 percent of the energy emitted from incandescent lights is in the form of light; the other 90 percent is heat. For each incandescent you replace with a CFL, you will reduce carbon-dioxide emissions from power plants by more than 700 pounds over the life of the bulb. The EPA estimates that if the lights in just one room in every U.S. home were switched to CFLs, we'd reduce carbon-dioxide emissions by over 1 trillion pounds.
Although CFLs initially cost more than incandescent bulbs, they last up to 20 times longer and use 75 percent less energy, making them an extremely profitable investment.
Recommendation: Replace incandescent bulbs with CFLs that screw in like conventional bulbs.
∗ Light pipes. Light pipes, also called solar tubes, provide natural light for the homes interior or in areas where other issues, such as privacy in a bathroom, restrict the use of windows. The light output can be significant: a 13-inch diameter tube can light about 200 square feet of space. High-quality units are well-insulated, so they lose little heat in the winter and gain little heat in the summer.
Recommendation: Light pipes run from the ceiling through the attic space to the roof, where skylight placement is not always feasible or is too expensive. The efficiency of light pipes can be improved by constructing the tubes of insulating material or by wrapping them with insulation.
∗ High-efficiency toilets. Toilets that use less than 1.3 gallons per flush (gpf) are called high-efficiency toilets (HETs). This category includes dual-flush toilets, 1.0-gpf pressure-assist toilets and conventional gravity-fed toilets. HETs perform well and enable homeowners to reduce water and sewer costs.
Recommendation: Install HETs that meet the rigorous performance requirements of North American water agencies. These fixtures are identified as meeting or exceeding a 250-gram waste-removal threshold, as defined in the Maximum Performance (MaP) testing report.
∗ On-demand hot-water circulation pumps. An on-demand hot-water circulation pump can send hot water to fixtures in seconds, without wasting water down the drain as you wait for it to get hot at the tap. The system uses a pump to rapidly move water from the water heater to fixtures, while cooler water in the line is sent back (via the cold-water line) to the water heater for reheating. The pump stops when the water at the fixture reaches a preset temperature.
Recommendation: Typically, only one pump is needed to supply hot water to all the fixtures in the home, although some systems might require additional pumps. Install the pump at the faucet furthest from the water heater.
∗ Mechanical ventilation. Mechanical ventilation systems, which include exhaust fans, systems that integrate with furnaces and stand-alone balanced ventilation systems, are used to deliver fresh air to today's tightly sealed homes. Whole-house ventilation systems improve indoor air quality by diluting pollutants. In addition, properly ventilating bathrooms will reduce the possibility of rot, mold and other problems caused by excess moisture.
Integrated systems, which use the furnace fan to bring in outside air through a dampered duct, should be equipped with controls to regulate the volume of air. Stand-alone systems include heat recovery ventilators (HRVs) and energy recovery ventilators (ERVs), which employ heat exchangers to recover heat and/or moisture from outgoing air.
Recommendation: When used for whole-house ventilation, exhaust fans should operate continuously and include provisions for filtered makeup air. Choose an Energy Star-qualified ventilation fan, which uses 65 percent less energy, on average, than standard models.
Exhaust bathroom ventilation fans to the outdoors, not to the attic. To ensure proper run-time and the adequate removal of moisture from the room, a timer or humidistat should be installed on the fan. Timers ensure the fan runs for a set time, usually 15-30 minutes. Humidistat controllers automatically switch the fan on when there is too much moisture in the air, and shut it down when the moisture level subsides. For quieter operation, look for bathroom fans with a sone rating of 1.5 or less.
∗ Radiant heating. Hydronic radiant heating systems circulate hot water through radiant floor panels, wall radiators or baseboard heaters located in different areas or zones of the house. They save energy by reducing thermal stratification and make for a more comfortable home.
Recommendation: Hydronic heating is most practical when installed with radiant heating distribution in slab-on-grade foundations in one-story houses. Use hydronic radiant heating instead of forced-air heating in homes that do not have to be cooled, or when comfort requirements are rigorous. The hydronic system can be fed by an efficient boiler or water heater that provides hot water for both domestic use and space heating. Install slab edge insulation with a minimum of R-5. The system should be designed in accordance with Radiant Panel Association guidelines by an RPA-certified installer.
∗ Photovoltaic (PV) panels. PV systems convert solar energy into electricity when sunlight strikes the PV cells. Benefits include lower utility costs, reduced emissions by fossil-fuel-burning power plants, reduced need for the development of new power plants and improved energy security.
Recommendation: For cost and appearance, the best location for PV modules is flush on south- or west-facing roofs. More energy is produced annually by south-facing modules, but west-facing modules can help reduce the system peak load and take advantage of time-of-use rates offered by some utilities. For tile roofs, building-integrated modules are usually easier to install and are more attractive. For other roof types, specially designed racks for mounting the PV panels are available.
∗ Solar hot water. A solar water-heating system uses solar panels to heat water, which is then stored for domestic hot-water use. The preheated water is typically delivered to a standard water heater for storage.
As a result of new technologies, reliable products and rising natural gas prices, solar water heating is more cost-effective than ever. Many solar water-heating systems can provide all the hot water needed during summer months and will save more than 50 percent of the energy normally used for heating water. Solar hot-water systems can pay back their cost in as little as 10 years.
Recommendation: Use only solar water heaters that are SRCC (Solar Rating and Certification Corp) certified. Provide sufficient south-facing roof area for collectors, make sure the roof structure can accommodate the weight of the system and make provisions near the conventional water heater for any additional mechanical equipment, such as storage tanks, pumps, pipes and controllers.
∗ Low- or zero-VOC paints. Most paints release volatile organic compounds (VOCs), a major air pollutant, into the home. Once outside the home, certain VOCs react with other pollutants, producing ground-level ozone (smog) that can affect human health. Low- and zero-VOC paints reduce these sources of pollution.
Recommendation: Low- or zero-VOC paints are available from most major manufacturers. They are applied just like conventional paint. Low-VOC paints contain less than 150 grams per liter (gpl) of VOCs for non-flat finishes and 50 gpl or less for flat finishes. Paints that contain less than 5 gpl of VOCs are classified as zero-VOC.
∗ Recycled-content carpet. Carpeting accounts for 70 percent of all floor coverings in the United States, and has been associated with a growing number of health and environmental problems. One option is to choose recycled-content carpet, which is made from recycled plastic bottles, wool, nylon or cotton.
Recycled-content carpet is often more resilient and colorfast than carpet made from virgin fibers. It is available in broadloom or carpet tiles at a price that is comparable to conventional carpet. Recycled-content underlayment and padding also are available.
∗ Fiber-cement exterior siding. Fiber-cement siding is composed of cement, sand and cellulose fibers. It's available in 4- to 12-inch lap planks or 4-by-8-foot sheets. It is textured to look like wood lap siding or stucco, but is more durable in fact, it's often warranted to last 50 years. It won't warp, twist, melt or burn, is resistant to moisture and termites, inhibits fungal growth and holds paint well. Using fiber-cement siding reduces the demand for old-growth redwood or cedar siding. It also may reduce homeowner's insurance rates, especially in fire-prone areas.
Recommendation: Replace conventional wood siding with fiber-cement siding. It is available primed and painted.
∗ Recycled-content decking. There are two types of recycled-content decking: plastic lumber and composite lumber. Plastic lumber contains only recycled plastic resins, while composite lumber is made by combining recycled wood fiber and recycled plastic resins that are then formed into deck boards.
The durability of these materials is greater than that of wood, providing cost savings to the homeowner over the life of the product. Recycled-content decking will not rot, crack or splinter, and does not require staining. It eliminates the need to use old-growth trees for decking.
Recommendation: Use recycled-content decking in all deck applications, excluding structural applications, as a replacement for old-growth redwood, cedar or pressure-treated pine. Beware of plastic decking that uses virgin materials. It's best for the environment to use recycled materials, so look in the manufacturer's literature for information on recycled content.
∗ High-efficiency irrigation systems. As the demand on our water resources increases, efficient lawn and garden irrigation becomes more and more vital. High-efficiency irrigation systems minimize overspray and evaporation, and reduce runoff, dramatically reducing landscape water use while preventing plant disease and minimizing weed growth that results from over-watering.
Efficient systems include drip and bubbler irrigation technologies, which apply water to the soil at the plant root at an appropriate rate so it can be absorbed by the soil. Similarly, low-flow sprinkler heads apply water uniformly and slowly. Smart irrigation controllers, which use weather-based information to monitor and control irrigation systems, can reduce outdoor water usage by 25 percent or more.
Recommendation: Install drip, subsurface drip or low-flow sprinklers in place of standard sprinkler systems for all landscape applications. Design the irrigation system to meet the requirements of your local conservation ordinance.
∗ Salvaged or recycled-content landscape materials. Landscaped areas present many opportunities for using salvaged or recycled materials. Recycled plastic or recycled composite lumber makes a durable landscape edging. Use broken concrete for retaining walls or paths and tumbled waste glass for walkways. For landscaping and hardscaping (planting beds, patios, decks, walls, walkways and driveways), recycled plastics or composites are generally more durable than wood, do not rot, crack or splinter, and do not require ongoing wood treatments.
Recommendation: Use salvaged or recycled-content materials for hardscape and other landscape features (edging, benches, play equipment). If recycled plastic or composite lumber is not appropriate, use sustainably harvested wood (certified by the FSC).
Kim Master is a senior associate at What's Working, Inc., a Boulder, Colo.-based greenbuilding consultancy. She's also the executive director for the Boulder Green Building Guild.