This spring, a partnership between the International Code Council (ICC) and the National Association of Home Builders (NAHB) plans to release a new green building standard, adding to an already dizzying array of green standards confronting affordable housing developers. Here's a list of the most important:

The National Green Building Standard

Local officials will soon be able to add the National Green Building Standard to their local building codes. Written by NAHB and ICC, the organization that creates the majority of building codes, the standard will go to the American National Standards Institute for approval this spring.

The idea is to offer local officials a green standard to add to their building codes before these officials make one up for themselves without input from the development community. The danger is real: Cities like Los Angeles and Washington, D.C., are already moving toward requiring all new buildings over a certain size to meet the Leadership in Energy and Environmental Design (LEED) standard created by the U.S. Green Building Council, which requires an independent certification process. In contrast, the National Green Building Standard will be enforced by local building inspectors.

The authors received input from U.S. Green Building Council, along with industry organizations such as the National Apartment Association and the National Multi Housing Council, making sure to avoid conflicts with existing building codes and creating a reasonable standard that will be attainable by developers.

Leadership in Energy and Environmental Design

The LEED standard is rapidly gaining acceptance among affordable housing developers since the release of the LEED for Homes standard this year.

LEED gives projects the stamp of approval of the U.S. Green Building Council. However, for years, the only LEED standard available to affordable housing developers, LEED for New Construction, was created around the needs of tall office buildings. LEED for New Construction encouraged developers to ban smoking and hire expensive commissioning agents to examine green equipment, although apartment buildings are much less likely than offices to include complicated technologies like water recycling plants that need to be checked.

The new LEED for Homes standard is much better suited to smaller residential projects. It costs $50,000 to be certified for LEED for Homes, a third of the cost to certify for LEED for New Construction. Under LEED for Homes, a wave of new LEED-certified affordable projects has appeared in states from Florida to Colorado.

The LEED standards, which award points for various green elements, can seem either strict or flexible, depending on where developers are building. That's because developers working in cities are likely to begin the process with points already won for building near mass transit, at relatively high density, and on brownfield sites. They developers have to do relatively little extra work to meet the LEED standards compared to developers building, for example, on the plains of Nebraska.

Enterprise Green Communities

In several states, the affordable housing officials that reserve low-income housing tax credits are favoring applications from projects that meet the Enterprise Green Communities standards created by Enterprise Community Investment, Inc.

That's in part because until recently the relatively practical and easy-to-use Enterprise standard was one of very few national green building standards designed around the needs of apartment buildings, according to developers. The affordable developers that work with Enterprise are also rapidly gaining experience in meeting the standard.

Federal Energy Star Standard

The federal Energy Star standard for energy efficiency is included in many green standards, like LEED, as the foundation of energy efficiency.