Green construction need not be complicated or cost-prohibitive, experts told attendees during two presentations at the Pacific Coast Builders Conference (PCBC) June 26.
"Building green, energy-efficient homes doesn't have to be rocket science," said construction consultant Steve Easley, owner of Steve Easley & Associates. "You can build very efficient homes at very low cost."
The following collection of "attainable sustainable" building practices from presenters at the two sessions could help make your projects a little greener—without requiring much green:
In most green building certification programs, energy efficiency accounts for a lion's share of the points, Easley said. Plus, it's appealing to homeowners. "Consumers want homes that have reduced operating costs," he said.
In thinking about air conditioning, many pros' first thought is about the system's seasonal energy efficiency ratio (SEER), Easley said. Instead, "Design the homes to use less air conditioning first," he suggested, using overhangs, proper orientation and landscaping, and efficient windows and building envelope products.
Ensure the air-conditioning unit is properly charged, Easley said. "Sixty-two percent of the time, the A/C system is mischarged," he added. The unit's SEER drops off with the wrong charge.
Use the Energy Star thermal bypass checklist
for subcontractors installing insulation, Easley said. The checklist shows common insulation mistakes and how to avoid them. When installers compress insulation, for instance, it quickly loses R-value.
Air leaks through common joints for framing and sheathing are a common problem, Easley said. Spray-foam insulation, combined with fiberglass insulation, offers an economical solution.
The most cost-effective energy-saving features vary by climate, noted Justin Dunning, director of the California Green Builder program. For example, in a climate like San Diego, where little heat or air conditioning is needed, tankless water heaters can provide a bigger return on investment than additional spending on HVAC, he said.
But there are some energy-saving measures that can benefit most builders regardless of climate, he said.
"It's always a good move to start with the insulation in the attic," he said. Adding more insulation there—up to R-38—is most cost-effective.
A one-coat stucco system, with stucco over a 1-inch-thick, R-4 EPS board, can create an R-17 wall and have a positive impact on air infiltration, Dunning said.
"There's quite a bit of money to be saved through third-party testing," Dunning said, to make sure ducts are tight and properly sealed.
Install moisture-resistant backer board such as Georgia-Pacific's DensShield Tile Backer
, Easley said. "Standard gypsum board is a perfect breeding ground for mold," he added.
Again, concentrating on initial design can provide the biggest bang for the buck, Easley noted. Avoid roof pitches intersecting with vertical wall planes, for instance, which can cause moisture-management problems.
Remember the basics. For example, reverse-shingling housewrap can cause huge problems, Easley said.
Use high-efficiency appliances and fixtures, Easley said. High-efficiency dishwashers use 5 gallons to 7 gallons of water per load, versus up to 12 gallons for standard machines. Using other high-efficiency fixtures, such as toilets, washing machines, showers, and faucets, can save an additional 50 percent, he added.
Use water-conserving landscaping, said general contractor Tenaya Asan, manager of the GreenPoint Rated program for Build It Green
. Avoid invasive species: "They suck up water from other plants," she said. Use reduced turf and native plants that require less water.
Use only drip, bubbler, or low-flow sprinkler irrigation systems and smart irrigation controllers, Asan suggested.
Don't use plants that need a lot of shearing, Asan said, because "green waste" takes up a lot of space in landfills.
Include a built-in recycling center in home designs to make recycling easier for homeowners, Asan suggested.
Jeffrey Lee is associate editor of Building Products magazine and ebuild.com, and a regular contributor to EcoHome.