A look at the 2021 IECC Residential Provisions for the Rating Industry Eric Makela – NBI | Jim Meyers - SWEEP
A look at the 2021 IECC Residential Provisions for the Rating Industry
3 Hello! I am Eric Makela I am Jim Meyers Director of Codes at Director of the Buildings Program SWEEP – Southwest Energy NBI – New Buildings Institute Efficiency Project Presentation template by SlidesCarnival
New Buildings Institute (NBI) ▫ NBI is redefining energy efficiency in the built environment. ▫ Program Areas: ▪ Best practices in new and existing buildings ▪ Continuous code and policy innovation ▪ Zero energy leadership and market development
Four Foundations to Zero Carbon Policy https://newbuildings.org/making-the-transition-from-zero-energy-to-zero-carbon-building-policies/
SWEEP ▫ The Southwest Energy Efficiency Project (SWEEP) promotes greater energy efficiency in Arizona, Colorado, Nevada, New Mexico, Utah, and Wyoming. ▫ Focus includes buildings, industrial, utility programs, transportation electrification ▫ SWEEP has program support in 5 states
7 Todays Discussion Points ▫ 2021 IECC ▫ EV Ready ▫ Envelope ▫ Packages ▫ Testing ▫ ERI ▫ System Changes ▫ Electrification Ready ▫ Water heat ▫ Zero Energy ▫ Lighting
First Look ▫ ICC – governmental consensus process ▫ Approximately 300 proposals ▫ More stringency ▫ New requirements DMW Magazine
1. Envelope Changes Highlights of significant changes for the 2021 IECC Envelope table AND REQUIREMENT
Insulation
Insulation ▫ Clarifying language about cavity insulation only for cavity, and continuous only for continuous (R402.1.3 R-value computation) ▫ + to &, ci to exterior ▫ Cavity only and exterior only options
Insulation ▫ Clarifying language about cavity insulation only for cavity, and continuous only for continuous (R402.1.3 R-value computation) ▫ + to &, ci to exterior ▫ Cavity only and exterior only options
Insulation ▫ 2021 IECC ▪ Increased slab insulation requirements
Insulation ▫ 2021 IECC Ceiling Insulation
Windows ▫ Fenestration u-factors ▪ From 0.32 to 0.30 in CZ 3 & 4 ▫ SHGC requirement now in CZ 5 & 4M ▪ From NR to 0.40 SHGC
Windows ▫ Area weighted average maximum values (Section 402.5) ▫ Maximum U-factor U- 0.40 CZ 4 & 5 ▪ U- 0.35 CZ 6 through 8 ▪ ▫ Maximum SHGC requirement SHGC 0.40 CZ 1 through 3 ▪ 2018 IECC
Windows ▫ Requirement for altitude and windborne debris ▫ Maximum U-factor of 0.32 in CZ 4M, CZ 5-8 ▫ Vertical fenestration only ▫ > 4000 feet elevation ▫ Windborne debris regions when required - IRC R301.2.1.2 US Atlantic Coast and Gulf of Mexico ▪ Hawaii, Puerto Rico, Guam, USVI, Samoa ▪ Pacific Coast not included ▪
Windows ▫ Requirement for altitude and windborne debris ▫ Maximum U-factor of 0.32 in CZ 4M, CZ 5-8 ▫ Vertical fenestration only ▫ > 4000 feet elevation ▫ Windborne debris regions when required - IRC R301.2.1.2 US Atlantic Coast and Gulf of Mexico ▪ Hawaii, Puerto Rico, Guam, USVI, Samoa ▪ Pacific Coast not included ▪
19 “ 2. Air Barrier & Testing Highlights of significant changes for the 2021 IECC Testing and Air Barrier requirements
Air Barrier and Insulation Table
Air Barrier and Insulation Table
Air Barrier and Insulation Table ▫ There was no air barrier criteria under plumbing ▫ Adds criteria for air sealing ▫ Removes current insulation language and accounts for insulation exterior to the wiring/plumbing/ obstruction
Air Barrier and Insulation Table ▫ One inch or less – air sealed
Air Barrier and Insulation Table ▫ Recessed light fixtures installed in the building thermal envelope shall be air sealed in accordance with Section R402.4.5 ▫ Duct shafts
Air Barrier and Insulation Table ▫ Foundations – basement, crawl space, slab
Leakage ▫ New definition for “Dwelling Unit Enclosure Area” ▪ The sum of the area of ceiling, floors, and walls separating a dwelling unit’s conditioned space from the exterior or from adjacent conditioned or unconditioned spaces. Wall height shall be measured from the finished floor of the dwelling unit to the underside of the floor above. ▫ Accepted alternative - Air leakage rate of 0.30 cfm/ft2 of enclosure area (ceiling, floors, walls) ▫ Applies to attached single and multifamily buildings AND ▫ Homes < 1500 ft2 GreenBuildingAdviso
Leakage ▫ New definition for “Dwelling Unit Enclosure Area” ▪ The sum of the area of ceiling, floors, and walls separating a dwelling unit’s conditioned space from the exterior or from adjacent conditioned or unconditioned spaces. Wall height shall be measured from the finished floor of the dwelling unit to the underside of the floor above. ▫ Accepted alternative - Air leakage rate of 0.30 cfm/ft2 of enclosure area (ceiling, floors, walls) ▫ Applies to attached single and multifamily buildings AND ▫ Homes < 1500 ft2 GreenBuildingAdviso
Leakage ▫ New section for multifamily testing ▫ R402.4.1.2.1 Buildings other than detached one-family dwellings ▫ Multi-zone buildings, two family dwellings, and townhouses shall be tested as a single zone, without inducing equal pressures in adjacent zones, or shall be tested as individual dwelling units. ▫ Numeric ACH – now 3.0/5.0 ACH (was three/five ACH)
Leakage ▫ Testing is mandatory ▫ The building or dwelling unit shall be tested for air leakage. ▫ Max leakage rate for any compliance path </ 5.0 ACH (ERI, performance) ▫ Leakage rate is added and prescriptive ▪ </5.0 ACH in CZ 1-2 ▪ </3.0 ACH in CZ 3-8 Green Building Advisor
30 3. System Changes Highlights of significant changes for the 2021 IECC Ventilation, ducts, mechanical
Duct Testing ▫ New requirement for duct leakage levels for any compliance path ▫ The maximum total leakage rate for ducts in any building or dwelling unit under any compliance path shall not exceed 8.0 cfm per 100 SF conditioned floor area ▫ Testing at rough or post construction ▫ Duct testing required for ducts in conditioned space
Duct Testing ▫ New requirement for duct leakage levels for any compliance path ▫ The maximum total leakage rate for ducts in any building or dwelling unit under any compliance path shall not exceed 8.0 cfm per 100 SF conditioned floor area ▫ Testing at rough or post construction ▫ Duct testing required for ducts in conditioned space
Duct Insulation Supply and return ducts ▫ ▪ Insulated to R-8 for ducts >/3.0 in ▪ Insulated to R-6 for ducts <3.0 in ▪ When outside conditioned space In floor cavities ▫ ▪ Air barrier between unconditioned space and the duct ▪ Min R-19 separating duct from unconditioned space In exterior walls ▫ ▪ Continuous air barrier between unconditioned space and duct ▪ Min R-10 separating duct from outside sheathing ▪ Fully insulated to drywall side
Mechanical Ventilation ▫ Update to whole-house fan efficacies ▫ Updates to latest ENERGY STAR version
Mechanical Ventilation ▫ Update to whole-house fan efficacies ▫ In addition to other fan types
Mechanical Ventilation ▫ Applies to CZ 7 & 8 ▫ ERV or HRV required ▫ Must be balanced ▫ >/ 65% sensible heat recovery efficiency
Mechanical Ventilation Ventilation systems - tested for minimum flow rates ▫ According to mfr instructions ▫ Or flow hood or box, flow grid, or other ▫ Used at inlet terminals/grilles, outlet terminals, ▫ or in ducts Written report submitted to building official ▫
4. Water Heat Highlights of significant changes for the 2021 IECC Hot water compactness, equipment efficiency and HERS H20
Water Efficiency ▫ Hot water (RE162-19) ▪ Compactness of hot water systems (Section R405 only)
Water Efficiency ▫ Hot water (RE162-19) ▪ Compactness of hot water systems (Section R405 only)
Water Efficiency ▫ Hot water Sources of hot water include water heaters, ▪ circulations loops heat trace pipe Rectangle shall include hot water source and ▪ termination points Shown on drawing plans – computed to nearest SF ▪ If more than one water heater then calculate ▪ separately and add together Basement counted as story if water heater located ▪
Compares to HERS H20 ▫ Evaluates indoor and outdoor water use Based on BSR/RESNET/ICC Std 850 ▫ Additional program requirements to include: ▫ ▪ Certification of raters | Quality Assurance | Approval of Software ▫ Ratable features - e.g. shower heads, faucets, toilet flush, irrigation Other attributes - house size, hot water distribution layout, pipe ▫ insulation Inspection Checklist | Inspection Guidance Document ▫
Water Heat ▫ 1. Storage gas water heater with a uniform energy factor (UEF) that meets the requirements of Table R403.5.1 ▫ 2. Storage electric water heater utilizing not less than 1.0 kW of on-site renewable energy ▫ 3. Heat pump water heater with a UEF >/ 2.0 ▫ 4. Tankless water heater ▫ 5. Grid-enabled water heater ▫ 6. Solar water heating system having a solar fraction of >/ 0.5
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