Energy Efficiency
As a result of the ongoing use of resources inherent in the energy use of any building, energy efficiency also comes at the top
of any green building priority list. The EPA/DOE Energy Star Home program serves as a basis for the energy efficiency component of many green building programs. Even though coastal environments are tempered by ocean water (cooler in summer and warmer in winter) compared with inland climates, they’re still punishing when you factor in the wind.
Building envelope — namely, insulation and air sealing measures. I think air sealing is by far the biggest issue for coastal contractors. Even a small constant breeze on a building can drive conditioned interior air through leaks. Special attention needs to be made to both window and door installation to reduce loses. Other critical areas are at building element connections (floor to foundation, wall to floor, roof to wall) and penetrations in walls and ceilings (see “Details: Airtight Framing,” January/February 2006 and “Air Leaks: Hidden Moisture Movers,” July/August 2007).
Window and door selection. Coastal homes usually have greater glazing area than inland homes. Choosing higher-efficiency (both lower U-factor and lower SHGC) windows and doors will have a greater impact on the energy performance of a coastal home (see “Selecting Windows for Coastal Homes,” March/April 2006). Interior shades are often overlooked from an energy-efficiency standpoint. They help building performance by reducing the heat gain of the summer sun and heat loss on a winter night. These are usually left to the clients after a builder closes out a project; I recommend coastal builders include this step as part of their scope of work.
HVAC design and equipment. Heating and cooling loads can be different when you’re building an ocean-side house compared with one just five miles inland. The HVAC equipment can often be downsized because peak summer and winter loads are less — this reduces the cost and complexity to install and reduces the operational cost both in money and environmental impact. Water Efficiency
Most coastal building environments have limited fresh water, and potable water is a limited resource. Plumbing codes and government regulations have driven us to green practices already with low-flow/low-consumption fixtures inside the home. More than half the water delivered to the average home is used for irrigation, so looking at ways to reduce water use outside so the homes you build or remodel will have less impact on local water supply is the first course of action.
Landscaping. Avoid the need for irrigation, but when necessary, use drip systems rather than sprinkler systems.
Rainwater collection. Underground tanks or simple rain barrels can store roof runoff for outside irrigation needs as well as indoor nonpotable purposes such as toilets. Collection and filtration systems are available for potable water use.
Think twice about graywater reuse. While some green proponents tout graywater reuse, coastal areas tend to be environmentally sensitive. Graywater reuse systems may not be permitted or wise for coastal zones.
