Stretch codes are building energy codes that require building construction above the minimum energy efficiency levels (i.e., base code) set in a state-adopted version of a national model code. The US Department of Energy (US DOE) notes that “stretch codes typically enhance building energy efficiency and may also contain additional considerations like building material impacts, water efficiency, renewable energy, and resilience or grid security.”
Jurisdictions such as local government may have a few pathways to voluntarily adopt a stretch code:
1) States may specify that a jurisdiction has the authority to adopt a stretch code, but not provide any specific language they must adopt;
2) States may write a specific stretch code that jurisdictions have the option to adopt;
3) States may specify that jurisdictions may adopt a more recent version of the national model code.
Stretch codes can be based on a percent improvement requirement, Energy Use Intensity (EUI), Home Energy Rating System (HERS) prescriptive requirements, minimum building performance thresholds, points systems, or programs such as Passive House (Phius or PHI) or the DOE Zero Energy Ready Home Program (ZERH). Once a jurisdiction adopts a stretch code, all construction in the jurisdiction that meets the specified criteria (e.g. new construction, large additions, and major renovations) must follow the code.
