Permitting of Specific Alternative Methods- ATAG
While building codes don’t prohibit the use of any method or material, approaches that fall outside the scope of the building code can be challenging for code officials to evaluate. To address the need for the further evaluation of alternative methods and materials, the Sustainable Building Program worked with the Building Division to develop an Alternative Technology Advisory Group (ATAG). ATAG is structured like Portland Oregon’s similar committee; it is comprised of building professionals who are interested in alternative methods and technologies who can help evaluate these materials for safety and code compliance. After reviewing existing research and codes on a selected alternative, the group makes recommendations to the Building Division. The Chief Building Official will then be able to refer to the group’s recommendation report in making determinations on individual projects utilizing the material or method. See more information about ATAG here and the bylaws for the group here.
The members of the 2020-2022 Alternative Technology Advisory Group were:
We thank them for their time and effort in serving on the committee!
Earthen Building Materials and Construction
ATAG began evaluating rammed earth construction in July 2020. That focus grew to include adobe and compressed earth block as the New Mexico Earthen Building Materials Code was recognized by the group as the best available resource for earthen construction. The group's findings were sent to the Chief Building Official on November 6th:
The Building Division then drafted an ordinance regarding earthen construction. Ordinance 2019-10 AMENDMENT PART XIII: Earthen Building Materials and Construction Code incorporates content from the New Mexico code, ATAG’s recommendations and the IBC code for adobe construction, resulting in a code for adobe, rammed earth and compressed earth block. See the Ordinance here.
The Ordinance was approved unanimously by the Planning & Zoning Commission, Building Safety & Advisory Board and the Board of Supervisors.
Earth Bag Construction
This construction method was the first one evaluated by ATAG. Unfortunately, the group found potential issues with settling and was unable to move forward with a recommended pathway to permitting one of these structures. However, due to interest in this building approach, the Building Division developed a policy allowing for the construction of a single-story earthbag dwelling of 750 square feet or less, with no walls taller than 8' and no domed roof, using the methods described in the book Earthbag Building: The Tools, Tricks and Techniques, Mother Earth News Wiser Living Series Book 8. See the policy here. For structures larger than 750 square feet, sealed plans from a structural engineer will be required.
Shipping Container Construction
ATAG reviewed the 2021 International Building Code Section 3315 for Intermodal Shipping Containers, concluding their work in November, 2021. The group found that the code is not prescriptive, and that even with the code engineering would be required for a permit. The group's findings were sent to the Chief Building Official on December 1, 2021:
Due to the interest in shipping container construction in Coconino County and the added cost of needed structural engineering, the Sustainable Building Program asked for funding from the Board of Supervisors in FY24 to hire a structural engineer to create model structural plans that can be used by designers and architects to create a full submittal for building permitting. Sirius Structures has developed plans for both single container and double container configurations that are now available for a reuse fee of $1250. If you are interested in using these plans, please review them below to see if they will work with what you want to build. As these are only structural plans, you may need to work with an architect or designer to create a full plan set for permitting purposes.
Please contact Nina Schmidt at firstname.lastname@example.org or (928) 679-8882 if you would like to use these plans.
Coconino County adopted the 2018 International Residential Code appendix for strawbale construction. You can find it here.
The 2021 International Residential Code included an appendix for cob construction. Coconino County is on a 6-year adoption interval and did not adopt the 2021 code series. It is anticipated that the 2024 IRC will also include this cob appendix and that it will look much like the 2021 appendix. We anticipate that the appendix will be adopted by Coconino County during the 2024 adoption process, which will likely conclude at the beginning of 2025.
Rocket Mass Heaters
ATAG reviewed "Rocket Mass Heaters: Superefficient Woodstoves YOU Can Build" by Ianto Evans and Leslie Jackson. We also consulted with County Building Inspector Donnie Newton, a former wood burning appliance installer. The group had concerns about differential expansion of materials within the stove, and the potential of escaping gases. To be compliant with code, wood burning appliances must be certified and undergo rigorous testing. It was determined that numerous problems could arise in the construction of a rocket mass heater that could lead to deadly outcomes. The group decided to not recommend approval of this technology to the Chief Building Official. Instead, it is recommended that customers interested in this technology consider a code compliant masonry fireplace or masonry heater instead.
ATAG found limited information on how traditional hogans are built, and learned that there are potentially many different building approaches. Due to this, we were unable to evaluate these structures for structural integrity and code compliance. If you are interested in building a traditional hogan for ceremonial purposes, we recommend you work directly with the Chief Building Official, Adam Hicks. If you are interested in building a hogan for residential purposes, we have identified a resource for residential hogan plan sets: CG Solutions, Clifton Grey Eyes.
Earthship Gray Water Treatment Planters for Toilet Flushing
Current Earthship Biotecture design includes a series of indoor gray water planters from which the effluent is pumped to a toilet for use in flushing. The toilet is dual plumbed, with separate gray water and potable water lines (the plumbing to the toilet is manually switched). The code for using gray water for toilet flushing, section P2911 of the 2018 IRC, requires that the treatment unit be certified to NSF 350 standards. We met with Michael Reynolds of Earthship Biotecture, and he was willing to take a sample of effluent from an existing Earthship planter system for testing to the parameters of NSF 350. Unfortunately, we didn't have the funding to pay for the tests. If a customer would like to pursue the use of this technology, it is possible that this offer will still stand. The current Chief Building Official at the time of this method evaluation, Adam Hicks, said that if the existing Earthship planter met the requirements of the NSF 350 testing parameters, that he would permit a similar planter with the stipulation that it also pass the test of meeting the NSF parameter limits at completion of the project.