Decatur, GA Mandates High-Performance Building Certification for Homes

RTAblog_2014_1118_DecaturLogoDecatur, GA’s City Commission approved an overhaul of its zoning ordinance last night. The updated ordinance includes mandates for high-performance building certifications for residential and commercial construction: new construction and renovations.

The City of Decatur (just east of Atlanta) has been working with interested parties to re-work its existing zoning, storm water and tree ordinances over the past year. Much of the work was organizing existing language and addressing conflicts in the ordinances. The 412-page consolidation of city ordinances is called the Unified Development Ordinance (UDO).

What’s Included
Article 10 of the UDO covers “Buildings and Fire”. Section 10.1.6, titled “High Performance Building Standards”, applies to one and two-family dwellings, multifamily dwellings and commercial|public use buildings. The portion on one and two-family dwellings (that’s single-family homes and duplexes) reads:

A. Single-Family and Two-Family Residential Standards

1. Applicability.

The following standards apply to:

a. Any newly constructed building containing attached or detached single-family dwelling units, two-family dwelling units, live-work, or an accessory dwelling units; and

b. Any substantial improvement to an existing building containing attached or detached single-family dwelling unites, two-family dwelling units, live-work or an accessory dwelling units.

A “substantial improvement” is defined as “any combination or repairs, reconstruction, alteration or improvements to a building where the cost of the construction exceeds 50% of the fair market value of the structure prior to improvement”. The definition goes on to describe how to determine fair market value.

The definition of substantial improvement should rule out certification requirements for relatively small projects like kitchen and bath renovations; typical maintenance requirements like replacing your roof or air conditioner; and projects like adding a deck or terrace.

What’s Required
The second part (again for one and two-family dwellings) explains the certification requirements. It reads:

A. Single-Family and Two-Family Residential Standards

2. High Performance Building Certification

All buildings subject to this paragraph must comply with one of the following:

a. Silver Certification using the current version of the National Green Building Standard-ICC 700-2012; or

b. Any level of certification using the current version of LEED for Homes; or

c. Any level of certification using the current version of the EarthCraft House or the EarthCraft Sustainable Preservation program.

The National Green Building Standard is the only one of the three that’s developed using a public process – interested parties are invited to propose changes each time the standard is updated. It was developed through a partnership with the National Association of Home Builders and International Code Council.

The LEED for Homes program was created by the U.S. Green Building Council. The EarthCraft program was created by the Southface Energy Institute in Atlanta.

What’s Exempted
The residential portion of the UDO includes three exemptions that must be demonstrated by the applicant to avoid the mandate for certification. In an abbreviated form, they are:

1. The least expensive allowed project certification and verification fees exceed 10% of the construction costs.

2. The building is a designated historic building and the Historic Preservation Commission has denied a certificate of appropriateness necessary for compliance with these requirements.

3.  The building is a historic structure or eligible for listing on the National Register of Historic Places, and when compliance with these requirements would case the building to cease to be a historic structure.

Those are relatively narrow exemptions so almost all new construction and substantial renovations will have to be certified under one of the three programs listed.

In Addition
The newly-adopted UDO also contains language about air sealing to prevent energy loss through the floor, walls and ceilings of the house. The air sealing requirement is more stringent than the current Georgia energy code (the 2009 IECC with Georgia amendments). Because the code mandates tighter construction, it also mandates a whole-house ventilation system. You can find these mandates in “3. General Requirements”.

In Conclusion
This is a significant change from the current Georgia building code to a “code plus” approach. While it often seems as though these changes are driven by energy efficiency, they should also improve the health and comfort of people living in high-performance certified homes. This comes at a price though the cost of third-party certification should be tiny when compared to the benefits of a healthier, more comfortable and more efficient home.

As always, if you’ve got a comment or question, please share it below. Thanks!

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