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The 2012 Washington Residential Energy Code (WREC) updates the previous 2009 code, effective July 1, 2013. This overview, presented by Ben Larson from Ecotope, outlines key provisions, compliance options, and energy savings metrics. The new format aligns with the IECC standards, maintaining many prior provisions while redefining climate zones. Key to the 2012 code is achieving a 70% reduction in building energy use by 2031. The challenges with individual efficiency measures and recommendations for packaging strategies are discussed, highlighting the need for ongoing improvements in energy conservation.
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Washington Residential Energy Code 2012: Overview 17 December 2013 Ben Larson, Ecotope
Code History and Overview • WA Energy Code updated on three year cycle. Previous code was 2009. Current is 2012. Effective 1 July 2013. • http://www.energy.wsu.edu/BuildingEfficiency/EnergyCode.aspx • Code format changed from WA own to layout of IECC. Most provisions from previous codes retained. • Energy codes set the new construction baseline for most efficiency measures • Presentation Overview: • Code Description and Provisions • Compliance Options • Energy Use and Savings • Setting the baseline for efficiency measures
Climate Zones now follow IECC designation. All counties in WA are 4M or 5 except for four counties in the north east: Okanogan, Ferry, Stevens, Pend Oreille are IECC Zone 6 Of those, only Ferry is the PNW Heating Zone 3, the rest are HZ 2 Overall, little change in the base envelope requirements from 2009. Climate zone reassignment may have slightly relaxed the wall insulation requirement for the formerly WA Zone 2 locations Envelope
Additional Requirements • Meet all of the prescriptive requirements and then obtain 1 point in 2009 and 1.5 points in 2012 from the following options:
Which Options Are Selected? • This is a common problem – it exists for the OR code, the previous WA code, and for EnergyStar in the Northwest. • There is no certain answer to the question because any answer is a prediction. • A possible approach: • estimate builder option selection based on cost and current market saturations of heating systems, foundation types, and house sizes
WA Code Over the Years Target:70% reduction in building energy use by 2031 per WA SB 5854
What about Conservation Measures? • New construction house characteristics (baseline) can now differ between houses • Scenario 1a: Ducts inside • Baseline house has Options 4 (ducts inside) and 5a (low flow fixtures) • A ducts inside efficiency measure has zero savings compared to this baseline • Scenario 1b: Ducts inside • Baseline house has Options 3b (heat pump upgrade) and 5a (low flow fixtures) • Adding ducts inside to this baseline house does produce energy savings • Scenario 2: Upgraded Heat Pump to HSPF 9.0 • Baseline house has Options 3b (heat pump upgrade to HSPF 8.5) and 5a (low flow fixtures) • The savings from the measure is the difference between an HSPF 8.5 and 9.0 heat pump • Savings from any individual new construction efficiency measure is not guaranteed.
What is the Best Baseline? • For a given measure, the baseline changes and depends on what code path was selected. • HSPF 9.0 measure would have an HSPF 8.5 baseline. • Ducts inside measure has a ducts inside baseline (mostly) • To get reliable savings from measures in WA for new construction, they will need to be bundled and packaged up
Existing Measure Package Examples • EnergyStar • Montana House • BuiltGreen • Eco-Rated and High Performance Manufactured Homes
Conclusion and Recommendations • WA Residential Code improved 9-10% over 2009 • Individual measures are challenged, including: • Heat pump upgrades, interior ducts, efficient DHW tanks, HPWHs, and showerheads • These UES measures need to be reexamined under the new baseline • Recommend avoiding individual measures in new construction in favor of packages • Existing EnergyStar needs revamp for WA • Other, additional packages can be created • Picking additional items off the options list can also form the basis of a conservation measure (scenario 1b)
Additional Slides Follow Ben Larson Ecotope ben@ecotope.com 206.322.3753