Page 81 - 2020 SDCA Project

Building System Specifications

Table 1. Optimized Building Performance Implementation Requirements Table

Refer to below table for detail and level of achievement recommendations for each category.

Building System Prototype Value Reference System Description
Specification

Walls R-Value ≥ 20 IECC 2012 3 inch rigid XPS

Roof R-Value ≥ 30 IECC 2009 5.5 inches of closed-cell spray foam in truss cavity

Floor R-Value ≥ 19 IECC 2012 Fiberglass-batts underneath floor, if applicable

Windows U-Value ≤ 0.3 ENERGY STAR NFRC Certified Window

SHGC ≤ 0.25 ENERGY STAR NFRC Certified Window

Air Leakage ACH50 ≤ 3 IECC 2012 Achieve continuous air barrier by sealing all wall, ceiling, and floor
penetrations to the outside

Mechanical Constant CFM 20 ASHRAE 62.2 Energy Recovery Ventilator (ERV); ducts deliver fresh air
Ventilation

Space Conditioning SEER ≥ 14.5 ENERGY STAR Ductless mini-split heat pump

HSPF ≥ 8.2 ENERGY STAR

Water Heater EF ≥ 0.90 ENERGY STAR Tankless; gas

Appliances ENERGY STAR ENERGY STAR certified, if applicable

Lighting ENERGY STAR LED; ENERGY STAR certified

Plumbing fixtures Gallons Per 0.5 WaterSense Low-flow bathroom sinks
Minute (GPM)

Gallons Per 1.5 WaterSense Low-flow kitchen sink/shower

Minute (GPM)

Gallons Per ≤ 1.28 WaterSense Dual-flush water closets
Flush (GPF) SDCA 81