Besides saving energy, natural daylight is beneficial to our health and productivity. We consider as “green” products that enable us to bring daylight into a building, including specialized commercial skylights, fiber-optic daylighting systems, lightshelves, and tubular skylights.
Before specifying efficient heating and cooling equipment, it’s important to do what we can to reduce heating and cooling loads. Insulation is one of the key products to consider here, but because there are so many insulation products on the market, we look for additional benefits. Examples include cellulose insulation with recycled content, mineral wool insulation with no flame retardants, and fiberglass insulation with no formaldehyde binders. Other products in this area are high-performance windows and glazings, products that contribute to building airtight envelopes, products that reduce thermal bridging, and window-retrofit products.
With products in this area under constant development, we are always refining our approach. For example, as we have learned about insulation products with hazardous flame retardants and blowing agents that have high global warming potential, we have removed those products from GreenSpec, pending manufacturing changes. We encourage building professionals to pressure manufacturers for those changes through specification language and purchasing decisions.
While resilience—the ability to weather natural disasters and maintain livable conditions in the aftermath of disruptive events—is mostly an issue of building design and community preparedness, certain products can help. For example, almost all heating systems require electricity to operate even if their primary fuel is oil, gas, or wood pellets; systems that allow operation even if grid electricity is not available are more resilient in the event of power outages. Rainwater harvesting, water storage, composting toilets, and waterless urinals contribute to resilience not only in drought-prone areas but also during power outages in any home dependent on well water. Solar water heating systems that can operate without utility power, and back-up power systems that are more energy-efficient than standard generators, may have this attribute.
Hella exterior blinds help control daylighting while reducing glare and cooling loads in commercial buildings. Distributed in the U.S. by Savannah Trims, Hella’s aluminum venetian blinds are available with slat sizes of 50 mm (2.0"), 80 mm (3.1"), and 100 mm (4.0"). All models come with lateral tensioning, options for light control functions, and manual crank or electrical operation. A variety of side rails are available for the 80 and 100 mm models. Savannah Trims also offers roller blinds with two shapes of aluminum alloy slats that are manufactured to hold their shape and for optimum stacking. Plastic inserts in the guide rails minimize noise. These blinds can block over 90% of incoming light and can be controlled by occupants or by building-management systems. Available in a variety of heights, widths, and colors.
GreenSpec lists exterior window and glazing attachments that reduce solar heat gain or redirect daylight, providing important energy conservation benefits while improving light quality for occupants. Exterior shade or screening devices are generally much more effective at reducing solar heat gain than their interior counterparts.
Exterior roller shades (or roller screens) are most commonly polyester fabric with either an acrylic or a PVC finish. The PVC finish adds durability to the polyester base fabric and maintains flexibility for rolling. While the PVC coatings improve durability, there are life-cycle environmental and health hazards with PVC. As alternative finish coatings become available, we will reassess our GreenSpec criteria for this section in favor of products with non-PVC finish coatings.
Exterior roller shutters are typically lightweight metal louvers that provide security and storm protection, in addition to solar heat gain reduction. Usually made of baked enamel aluminum, exterior roller shutters are usually motorized.
Exterior solar screens can be either panels or roller shades. The fabric cores of the solar screen can be fiberglass or polyester. The screen strands are usually PVC-coated to improve durability and UV-resistance.
While solar screens have openness factors that provide significant view, exterior shades are tightly woven enough to be either opaque or translucent, providing no direct view.
For additional information on exterior rollers shades, screens and shutters, see GreenSpec's partner site WindowAttachments.org.
EAc1: Optimize Energy Performance
EAp2: Minimum Energy Performance
EQc8.1: Daylight and Views—Daylight 75% of Spaces
EQc8.2: Daylight and Views—Views for 90% of Spaces
IEQc2.4: Daylight and Views
IEQc8.1: Daylight and Views—Daylight
IEQc8.2: Daylight and Views—Views
Ratings and Commentary