Among the many residential amendments to the 2018 IECC approved by the BBRS in March of 2019, there is one in particular which could have a big impact on how residential buildings will be designed in non-stretch code communities going forward. This new requirement is a newly created amendment, Section R407 Additional Efficiency Packages. Those of you familiar with the commercial energy code may recognize this new section, considering that similar commercial requirements date back as far as the 2012 IECC.
R407 is a prescriptive requirement that will require designers and builders to choose one of three options to be incorporated into their building project. Those options are: (A) More efficient HVAC performance in accordance with R407.2 (i.e., furnaces or boilers with an AFUE of ≥ 95% or high-efficiency air- and ground-source heat pumps); (B) the use of heat recovery ventilation (HRV) system or energy recovery ventilation (ERV) system; or (C) a high efficiency water heater or solar thermal water heater in accordance with R407.3. (i.e., gas or propane water heaters with a UEF of ≥ 0.87; electric heat pump water heaters with a UEF of ≥ 2.2; or solar thermal water heating system with a gross collection area of ≥ 40 square feet and a total resource solar fraction of ≥ 75%).
The first and last options are clearly understood energy efficiency improvements, however HRV/ERVs may not be as familiar to some. These ventilation systems provide the ability to recover heat (sensible heat) or energy (sensible and latent heat) loss that occurs with the normal operation of a whole-house ventilation system. While HRV/ERVs may be more expensive than your normal whole-house ventilation system, the benefits of having a balanced ventilation system combined with improved energy efficiency may make this a go-to option for many.
(Credit: Mass Save®)