WSR 17-10-063
PERMANENT RULES
BUILDING CODE COUNCIL
[Filed May 2, 2017, 2:13 p.m., effective June 2, 2017]
Effective Date of Rule: Thirty-one days after filing.
Purpose: Makes changes to the Residential energy portion of the Washington State Energy Code for clarity, along with some editorial changes. Includes Sections R104.2.3, Plumbing rough-in inspection; R202, definition of Skylight; R402.1, General (envelope); R402.1.2, R-value computation; Table R402.1.1, Insulation and fenestration requirements by component (footnote C); R403.3.4, Duct leakage; R406.1, Scope (additional efficiency requirements); Table R406.2, Energy credits; R502.1.1.3, Heating and cooling systems (additions); R503.1.3, Service hot water systems (alterations).
Citation of Existing Rules Affected by this Order: Amending WAC 51-11R-10400, 51-11R-20219, 51-11R-40210, 51-11R-40211, 51-11R-40320, 51-11R-40610, 51-11R-40621, 51-11R-50200, and 51-11R-50300.
Statutory Authority for Adoption: RCW 19.27A.025, 19.27A.045, 19.27A.160.
Other Authority: RCW 19.27.074.
Adopted under notice filed as WSR 17-04-087 on January 31, 2017.
Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 0, Amended 0, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.
Number of Sections Adopted at Request of a Nongovernmental Entity: New 0, Amended 0, Repealed 0.
Number of Sections Adopted on the Agency's Own Initiative: New 0, Amended 0, Repealed 0.
Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 0, Amended 9, Repealed 0.
Number of Sections Adopted Using Negotiated Rule Making: New 0, Amended 0, Repealed 0; Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.
Date Adopted: April 21, 2017.
Steve K. Simpson
Council Chair
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-10400 Section R104—Inspections.
R104.1 General. Construction or work for which a permit is required shall be subject to inspection by the code official or his or her designated agent, and such construction or work shall remain accessible and exposed for inspection purposes until approved. It shall be the duty of the permit applicant to cause the work to remain accessible and exposed for inspection purposes. Neither the code official nor the jurisdiction shall be liable for expense entailed in the removal or replacement of any material, product, system or building component required to allow inspection to validate compliance with this code.
R104.2 Required inspections. The code official or his or her designated agent, upon notification, shall make the inspections set forth in Sections R104.2.1 through R104.2.5.
R104.2.1 Footing and foundation inspection. Inspections associated with footings and foundations shall verify compliance with the code as to R-value, location, thickness, depth of burial and protection of insulation as required by the code and approved plans and specifications.
R104.2.2 Framing and rough-in inspection. Inspections at framing and rough-in shall be made before application of interior finish and shall verify compliance with the code as to types of insulation and corresponding R-values and their correct location and proper installation; fenestration properties (U-factor and SHGC) and proper installation; and air leakage controls as required by the code and approved plans and specifications.
R104.2.2.1 Wall insulation inspection. The building official, upon notification, shall make a wall insulation inspection in addition to those inspections required in Section R109 of the International Residential Code. This inspection shall be made after all wall and cavity insulation is in place and prior to cover.
R104.2.3 Plumbing rough-in inspection. Inspections at plumbing rough-in shall verify compliance as required by the code and approved plans and specifications as to types of insulation and corresponding R-values and protection, and required controls.
R104.2.4 Mechanical rough-in inspection. Inspections at mechanical rough-in shall verify compliance as required by the code and approved plans and specifications as to installed HVAC equipment type and size, required controls, system insulation and corresponding R-value, system air leakage control, programmable thermostats, dampers, whole-house ventilation and minimum fan efficiency.
EXCEPTION:
Systems serving multiple dwelling units shall be inspected in accordance with Section C104.2.4.
R104.2.5 Final inspection. The building shall have a final inspection and not be occupied until approved.
R104.3 Reinspection. A building shall be reinspected when determined necessary by the code official.
R104.4 Approved inspection agencies. The code official is authorized to accept reports of third-party inspection agencies not affiliated with the building design or construction, provided such agencies are approved as to qualifications and reliability relevant to the building components and systems they are inspecting.
R104.5 Inspection requests. It shall be the duty of the holder of the permit or their duly authorized agent to notify the code official when work is ready for inspection. It shall be the duty of the permit holder to provide access to and means for inspections of such work that are required by this code.
R104.6 Reinspection and testing. Where any work or installation does not pass an initial test or inspection, the necessary corrections shall be made so as to achieve compliance with this code. The work or installation shall then be resubmitted to the code official for inspection and testing.
R104.7 Approval. After the prescribed tests and inspections indicate that the work complies in all respects with this code, a notice of approval shall be issued by the code official.
R104.7.1 Revocation. The code official is authorized to, in writing, suspend or revoke a notice of approval issued under the provisions of this code wherever the certificate is issued in error, or on the basis of incorrect information supplied, or where it is determined that the building or structure, premise, or portion thereof is in violation of any ordinance or regulation or any of the provisions of this code.
AMENDATORY SECTION (Amending WSR 13-04-055, filed 2/1/13, effective 7/1/13)
WAC 51-11R-20219 Section R202.19—S.
SERVICE WATER HEATING. Supply of hot water for purposes other than comfort heating.
((SKYLIGHT. Glass or other transparent or translucent glazing material installed at a slope of less than 60 degrees (1.05 rad) from horizontal. Glazing material in skylights, including unit skylights, solariums, sunrooms, roofs and sloped walls is included in this definition.))
SLAB-ON-GRADE FLOOR. That portion of a slab floor of the building envelope that is in contact with the ground and that is either above grade or is less than or equal to 24 inches below the final elevation of the nearest exterior grade.
SMALL BUSINESS. Any business entity (including a sole proprietorship, corporation, partnership or other legal entity) which is owned and operated independently from all other businesses, which has the purpose of making a profit, and which has fifty or fewer employees.
SOLAR HEAT GAIN COEFFICIENT (SHGC). The ratio of the solar heat gain entering the space through the fenestration assembly to the incident solar radiation. Solar heat gain includes directly transmitted solar heat and absorbed solar radiation which is then reradiated, conducted or convected into the space.
STANDARD FRAMING. All framing practices not defined as "intermediate" or "advanced" shall be considered standard. (See Advanced Framed Wall, Intermediate Framed Wall).
STANDARD REFERENCE DESIGN. A version of the proposed design that meets the minimum requirements of this code and is used to determine the maximum annual energy use requirement for compliance based on total building performance.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-40210 Section R402.1—General.
R402.1 General (Prescriptive). The building thermal envelope shall meet the requirements of Sections R402.1.1 through R402.1.5.
EXCEPTION:
The following buildings, or portions thereof, separated from the remainder of the building by building thermal envelope assemblies complying with this code shall be exempt from the building thermal envelope provisions of this code.
 
1. Those with a peak design rate of energy usage less than 3.4 Btu/h ft2 (10.7 W/m2) or 1.0 watt/ft2 (((10.7 W/m2))) of floor area for space conditioning purposes.
 
2. Those that do not contain conditioned space.
 
3. Greenhouses isolated from any conditioned space and not intended for occupancy.
R402.1.1 Insulation and fenestration criteria. The building thermal envelope shall meet the requirements of Table R402.1.1 based on the climate zone specified in Chapter 3.
R402.1.2 R-value computation. Insulation material used in layers, such as framing cavity insulation((,)) or continuous insulation, shall be summed to compute the corresponding component R-value. The manufacturer's settled R-value shall be used for blown insulation. Computed R-values shall not include an R-value for other building materials or air films. Where insulated siding is used for the purpose of complying with the continuous insulation requirements of Table R402.1.1, the manufacturer must supply an ICC Report that the R-factor has been certified, or use R-5 per inch for extruded polystyrene, and R-6 per inch for polyisocyanurate rigid insulation.
R402.1.3 U-factor alternative. An assembly with a U-factor equal to or less than that specified in Table R402.1.3 shall be permitted as an alternative to the R-value in Table R402.1.1.
R402.1.4 Total UA alternative. If the total building thermal envelope UA (sum of U-factor times assembly area) is less than or equal to the total UA resulting from using the U-factors in Table R402.1.3 (multiplied by the same assembly area as in the proposed building), the building shall be considered in compliance with Table R402.1.1. The U-factors for typical construction assemblies are included in Appendix A in chapter 51-11C WAC. These values shall be used for all calculations. Where proposed construction assemblies are not represented in Appendix A, values shall be calculated in accordance with the ASHRAE Handbook of Fundamentals using the framing factors listed in Appendix A where applicable and shall include the thermal bridging effects of framing materials. The SHGC requirements shall be met in addition to UA compliance. When using REScheck, the U-factors calculated by the software based on component R-value descriptions are acceptable. For the base building UA calculation, the maximum glazing area is 15% of the floor area.
R402.1.5 Vapor retarder. Wall assemblies in the building thermal envelope shall comply with the vapor retarder requirements of Section R702.7 of the International Residential Code or Section 1405.3 of the International Building Code, as applicable.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-40211 Table R402.1.1—Insulation and fenestration requirements by component.
TABLE R402.1.1
INSULATION AND FENESTRATION REQUIREMENTS BY COMPONENTa
Climate Zone
Fenestration
U-Factorb
Skylightb
U-Factor
Glazed
Fenestration SHGCb, e
Ceiling
R-Valuek
Wood Frame Wallg, m, n
R-Value
Mass Wall
R-Valuei
Floor
R-Value
Below-
Gradec, m Wall R-Value
Slabd
R-Value & Depth
5 and Marine 4
0.30
0.50
NR
49
21 int
21/ 21
30
10/15/
21int+TB
10, 2 ft
For SI:
1 foot = 304.8 mm, ci = continuous insulation, int = intermediate framing.
 
a R-values are minimums. U-factors and SHGC are maximums. When insulation is installed in a cavity which is less than the label or design thickness of the insulation, the compressed R-value of the insulation from Appendix Table A101.4 shall not be less than the R-value specified in the table.
 
b The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration.
 
c "10/15/21+TB" means R-10 continuous insulation on the exterior of the wall, or R-15 on the continuous insulation on the interior of the wall, or R-21 cavity insulation plus a thermal break between the slab and the basement wall at the interior of the basement wall. "10/15/21+TB" shall be permitted to be met with R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulation on the interior or exterior of the wall. (("10/13" means R-10 continuous insulation on the interior or exterior of the home or R-13 cavity insulation at the interior of the basement wall.)) "TB" means thermal break between floor slab and basement wall.
 
d R-10 continuous insulation is required under heated slab on grade floors. See R402.2.9.1.
 
e There are no SHGC requirements in the Marine Zone.
 
f Reserved.
 
g Reserved.
 
h Reserved.
 
i The second R-value applies when more than half the insulation is on the interior of the mass wall.
 
j Reserved.
 
k For single rafter- or joist-vaulted ceilings, the insulation may be reduced to R-38.
 
l Reserved.
 
m Int. (intermediate framing) denotes standard framing 16 inches on center with headers insulated with a minimum of R-10 insulation.
 
n Log and solid timber walls with a minimum average thickness of 3.5 inches are exempt from this insulation requirement.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-40320 Section R403.3—Ducts.
R403.3 Ducts. Ducts and air handlers shall be in accordance with Sections R403.3.1 through R403.3.5.
R403.3.1 Insulation (Prescriptive). Ducts outside the building thermal envelope shall be insulated to a minimum of R-8. Ducts within a concrete slab or in the ground shall be insulated to R-10 with insulation designed to be used below grade.
EXCEPTION:
Ducts or portions thereof located completely inside the building thermal envelope. Ducts located in crawl spaces do not qualify for this exception.
R403.3.2 Sealing (Mandatory). Ducts, air handlers, and filter boxes shall be sealed. Joints and seams shall comply with either the International Mechanical Code or International Residential Code, as applicable.
EXCEPTIONS:
1. Air-impermeable spray foam products shall be permitted to be applied without additional joint seals.
 
2. For ducts having a static pressure classification of less than 2 inches of water column (500 Pa), additional closure systems shall not be required for continuously welded joints and seams, and locking-type joints and seams of other than the snap-lock and button-lock types.
R403.3.2.1 Sealed air handler. Air handlers shall have a manufacturer's designation for an air leakage of no more than 2 percent of the design air flow rate when tested in accordance with ASHRAE 193.
R403.3.3 Duct testing (Mandatory). Ducts shall be leak tested in accordance with WSU RS-33, using the maximum duct leakage rates specified.
EXCEPTION:
The total leakage or leakage to the outdoors test is not required for ducts and air handlers located entirely within the building thermal envelope. For forced air ducts, a maximum of 10 linear feet of return ducts and 5 linear feet of supply ducts may be located outside the conditioned space. All metallic ducts located outside the conditioned space must have both transverse and longitudinal joints sealed with mastic. If flex ducts are used, they cannot contain splices. Flex duct connections must be made with nylon straps and installed using a plastic strapping tensioning tool. Ducts located in crawl spaces do not qualify for this exception.
A written report of the results shall be signed by the party conducting the test and provided to the code official.
R403.3.4 Duct leakage (Mandatory). The total leakage of the ducts, where measured in accordance with Section R403.3.3, shall be as follows:
1. Rough-in test: Total leakage shall be less than or equal to 4 cfm (113.3 L/min) per 100 square feet (9.29 m2) of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the system, including the manufacturer's air handler enclosure. All registers shall be taped or otherwise sealed during the test. If the air handler is not installed at the time of the test, total leakage shall be less than or equal to 3 cfm (85 L/min) per 100 square feet (9.29 m2) of conditioned floor area.
2. Postconstruction test: Leakage to outdoors shall be less than or equal to 4 cfm (113.3 L/min) per 100 square feet (9.29 m2) of conditioned floor area((s)) or total leakage shall be less than or equal to 4 cfm (113.3 L/min) per 100 square feet (9.29 m2) of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer's air handler enclosure. All register boots shall be taped or otherwise sealed during the test.
R403.3.5 Building cavities (Mandatory). Building framing cavities shall not be used as ducts or plenums. Installation of ducts in exterior walls, floors or ceilings shall not displace required envelope insulation.
AMENDATORY SECTION (Amending WSR 13-04-055, filed 2/1/13, effective 7/1/13)
WAC 51-11R-40610 Section R406.1—Scope.
R406.1 Scope. This section establishes options for additional criteria to be met for one- and two-family dwellings and townhouses, as defined in Section 101.2 of the International Residential Code, and dwelling units in residential buildings to demonstrate compliance with this code.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-40621 Table R406.2—Energy credits.
TABLE 406.2
ENERGY CREDITS
OPTION
DESCRIPTION
CREDIT(S)
1a
EFFICIENT BUILDING ENVELOPE 1a:
0.5
 
Prescriptive compliance is based on Table R402.1.1 with the following modifications:
Vertical fenestration U = 0.28
Floor R-38
Slab on grade R-10 perimeter and under entire slab
Below grade slab R-10 perimeter and under entire slab
 
 
or
Compliance based on Section R402.1.4: Reduce the Total UA by 5%.
 
1b
EFFICIENT BUILDING ENVELOPE 1b:
1.0
 
Prescriptive compliance is based on Table R402.1.1 with the following modifications:
Vertical fenestration U = 0.25
Wall R-21 plus R-4 ci
Floor R-38
Basement wall R-21 int plus R-5 ci
Slab on grade R-10 perimeter and under entire slab
Below grade slab R-10 perimeter and under entire slab
 
 
or
Compliance based on Section R402.1.4: Reduce the Total UA by 15%.
 
1c
EFFICIENT BUILDING ENVELOPE 1c:
2.0
 
Prescriptive compliance is based on Table R402.1.1 with the following modifications: Vertical fenestration U = 0.22
Ceiling and single-rafter or joist-vaulted R-49 advanced
Wood frame wall R-21 int plus R-12 ci
Floor R-38
Basement wall R-21 int plus R-12 ci
Slab on grade R-10 perimeter and under entire slab
Below grade slab R-10 perimeter and under entire slab
 
 
or
Compliance based on Section R402.1.4: Reduce the Total UA by 30%.
 
1da
EFFICIENT BUILDING ENVELOPE 1d:
0.5
 
Prescriptive compliance is based on Table R402.1.1 with the following modifications:
Vertical fenestration U = 0.24
 
2a
AIR LEAKAGE CONTROL AND EFFICIENT VENTILATION 2a:
0.5
 
Compliance based on R402.4.1.2: Reduce the tested air leakage to 3.0 air changes per hour maximum and
 
 
All whole house ventilation requirements as determined by Section M1507.3 of the International Residential Code shall be met with a high efficiency fan (maximum 0.35 watts/cfm), not interlocked with the furnace fan. Ventilation systems using a furnace including an ECM motor are allowed, provided that they are controlled to operate at low speed in ventilation only mode.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the maximum tested building air leakage and shall show the qualified ventilation system.
 
2b
AIR LEAKAGE CONTROL AND EFFICIENT VENTILATION 2b:
1.0
 
Compliance based on Section R402.4.1.2: Reduce the tested air leakage to 2.0 air changes per hour maximum
and
 
 
All whole house ventilation requirements as determined by Section M1507.3 of the International Residential Code shall be met with a heat recovery ventilation system with minimum sensible heat recovery efficiency of 0.70.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the maximum tested building air leakage and shall show the heat recovery ventilation system.
 
2c
AIR LEAKAGE CONTROL AND EFFICIENT VENTILATION 2c:
1.5
 
Compliance based on Section R402.4.1.2: Reduce the tested air leakage to 1.5 air changes per hour maximum
 
 
All whole house ventilation requirements as determined by Section M1507.3 of the International Residential Code shall be met with a heat recovery ventilation system with minimum sensible heat recovery efficiency of 0.85.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the maximum tested building air leakage and shall show the heat recovery ventilation system.
 
3ab
HIGH EFFICIENCY HVAC EQUIPMENT 3a:
1.0
 
Gas, propane or oil-fired furnace with minimum AFUE of 94%, or gas, propane or oil-fired boiler with minimum AFUE of 92%.
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the heating equipment type and the minimum equipment efficiency.
 
3bb
HIGH EFFICIENCY HVAC EQUIPMENT 3b:
1.0
 
Air-source heat pump with minimum HSPF of 9.0
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the heating equipment type and the minimum equipment efficiency.
 
3cb
HIGH EFFICIENCY HVAC EQUIPMENT 3c:
1.5
 
Closed-loop ground source heat pump; with a minimum COP of 3.3
or
Open loop water source heat pump with a maximum pumping hydraulic head of 150 feet and minimum COP of 3.6
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the heating equipment type and the minimum equipment efficiency.
 
3db
HIGH EFFICIENCY HVAC EQUIPMENT 3d:
DUCTLESS SPLIT SYSTEM HEAT PUMPS, ZONAL CONTROL:
1.0
 
In homes where the primary space heating system is zonal electric heating, a ductless heat pump system shall be installed and provide heating to the largest zone of the housing unit.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the heating equipment type and the minimum equipment efficiency.
 
4
HIGH EFFICIENCY HVAC DISTRIBUTION SYSTEM:
1.0
 
All heating and cooling system components installed inside the conditioned space. This includes all equipment and distribution system components such as forced air ducts, hydronic piping, hydronic floor heating loop, convectors and radiators. All combustion equipment shall be direct vent or sealed combustion.
 
 
For forced air ducts: A maximum of 10 linear feet of return ducts and 5 linear feet of supply ducts may be located outside the conditioned space. All metallic ducts located outside the conditioned space must have both transverse and longitudinal joints sealed with mastic. If flex ducts are used, they cannot contain splices. Flex duct connections must be made with nylon straps and installed using a plastic strapping tensioning tool. Ducts located outside the conditioned space must be insulated to a minimum of R-8.
Locating system components in conditioned crawl spaces is not permitted under this option.
 
 
Electric resistance heat and ductless heat pumps are not permitted under this option.
Direct combustion heating equipment with AFUE less than 80% is not permitted under this option.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the heating equipment type and shall show the location of the heating and cooling equipment and all the ductwork.
 
5a
EFFICIENT WATER HEATING 5a:
0.5
 
All showerheads and kitchen sink faucets installed in the house shall be rated at 1.75 GPM or less. All other lavatory faucets shall be rated at 1.0 GPM or less.c
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the maximum flow rates for all showerheads, kitchen sink faucets, and other lavatory faucets.
 
5b
EFFICIENT WATER HEATING 5b:
Water heating system shall include one of the following:
Gas, propane or oil water heater with a minimum EF of 0.74
or
1.0
 
Water heater heated by ground source heat pump meeting the requirements of Option 3c.
or
 
 
For R-2 occupancy, a central heat pump water heater with an EF greater than 2.0 that would supply DHW to all the units through a central water loop insulated with R-8 minimum pipe insulation.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the water heater equipment type and the minimum equipment efficiency.
 
5c
EFFICIENT WATER HEATING 5c:
Water heating system shall include one of the following:
Gas, propane or oil water heater with a minimum EF of 0.91
or
1.5
 
Solar water heating supplementing a minimum standard water heater. Solar water heating will provide a rated minimum savings of 85 therms or 2000 kWh based on the Solar Rating and Certification Corporation (SRCC) Annual Performance of OG-300 Certified Solar Water Heating Systems.
or
 
 
Electric heat pump water heater with a minimum EF of 2.0 and meeting the standards of NEEA's Northern Climate Specifications for Heat Pump Water Heaters.
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall specify the water heater equipment type and the minimum equipment efficiency and, for solar water heating systems, the calculation of the minimum energy savings.
 
5d
EFFICIENT WATER HEATING 5d:
A drain water heat recovery unit(s) shall be installed, which captures waste water heat from all the showers, and has a minimum efficiency of 40% if installed for equal flow or a minimum efficiency of 52% if installed for unequal flow. Such units shall be rated in accordance with the CSA B55.1 standard and be so labeled.
To qualify to claim this credit, the building permit drawings shall include a plumbing diagram that specifies the drain water heat recovery units and the plumbing layout needed to install it and labels or other documentation shall be provided that demonstrates that the unit complies with the standard.
0.5
6
RENEWABLE ELECTRIC ENERGY:
For each 1200 kWh of electrical generation per housing unit provided annually by on-site wind or solar equipment a 0.5 credit shall be allowed, up to 3 credits. Generation shall be calculated as follows:
0.5
 
For solar electric systems, the design shall be demonstrated to meet this requirement using the National Renewable Energy Laboratory calculator PVWATTs. Documentation noting solar access shall be included on the plans.
 
 
For wind generation projects designs shall document annual power generation based on the following factors:
The wind turbine power curve; average annual wind speed at the site; frequency distribution of the wind speed at the site and height of the tower.
 
 
To qualify to claim this credit, the building permit drawings shall specify the option being selected and shall show the photovoltaic or wind turbine equipment type, provide documentation of solar and wind access, and include a calculation of the minimum annual energy power production.
 
Footnotes:
a Projects using this option may not use option 1a, 1b, or 1c.
 
b Projects may only include credit from one space heating option, 3a, 3b, 3c or 3d. When a housing unit has two pieces of equipment (i.e., two furnaces) both must meet the standard to receive the credit.
 
c Plumbing Fixtures Flow Ratings. Low flow plumbing fixtures (water closets and urinals) and fittings (faucets and showerheads) shall comply with the following requirements:
 
1 Residential bathroom lavatory sink faucets: Maximum flow rate - 3.8 L/min (1.0 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.
 
2 Residential kitchen faucets: Maximum flow rate - 6.6 L/min (1.75 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.
 
3 Residential showerheads: Maximum flow rate - 6.6 L/min (1.75 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-50200 Section R502—Additions.
R502.1 General. Additions to an existing building, building system or portion thereof shall conform to the provisions of this code as those provisions relate to new construction without requiring the unaltered portion of the existing building or building system to comply with this code. Additions shall not create an unsafe or hazardous condition or overload existing building systems. An addition shall be deemed to comply with this code where the addition alone complies, where the existing building and addition comply with this code as a single building, or where the building with the addition uses no more energy than the existing building. Additions shall be in accordance with Section R502.1.1 or R502.1.2.
R502.1.1 Prescriptive compliance. Additions shall comply with Sections R502.1.1.1 through R502.1.1.4.
R502.1.1.1 Building envelope. New building envelope assemblies that are part of the addition shall comply with Sections R402.1, R402.2, R402.3.1 through R402.3.5, and R402.4.
EXCEPTION:
Where nonconditioned space is changed to conditioned space, the building envelope of the addition shall comply where the UA, as determined in Section R402.1.4, of the existing building and the addition, and any alterations that are part of the project, is less than or equal to UA generated for the existing building.
R502.1.1.2 Heating and cooling systems. New heating, cooling and duct systems that are part of the addition shall comply with Sections R403.1, R403.2, R403.3, R403.5, and R403.6.
EXCEPTION:
The following need not comply with the testing requirements of Section R403.3.3:
 
1. Additions of less than 750 square feet.
 
2. Duct systems that are documented to have been previously sealed as confirmed through field verification and diagnostic testing in accordance with procedures in WSU RS-33.
 
3. Ducts with less than 40 linear feet in unconditioned spaces.
 
4. Existing duct systems constructed, insulated or sealed with asbestos.
R502.1.1.3 Service hot water systems. New service hot water systems that are part of the addition shall comply with Section ((R403.4)) R403.5.
R502.1.1.4 Lighting. New lighting systems that are part of the addition shall comply with Section 404.1.
R502.1.2 Existing plus addition compliance (Simulated Performance Alternative). Where nonconditioned space is changed to conditioned space the addition shall comply where the annual energy use of the addition and the existing building, and any alterations that are part of the project, is less than or equal to the annual energy use of the existing building when modeled in accordance with Section R405. The addition and any alterations that are part of the project shall comply with Section R405 in its entirety.
AMENDATORY SECTION (Amending WSR 16-02-127, filed 1/6/16, effective 7/1/16)
WAC 51-11R-50300 Section R503—Alterations.
R503.1 General. Alterations to any building or structure shall comply with the requirements of the code for new construction. Alterations shall be such that the existing building or structure is no less conforming to the provisions of this code than the existing building or structure was prior to the alteration.
Alterations to an existing building, building system or portion thereof shall conform to the provisions of this code as they relate to new construction without requiring the unaltered portions of the existing building or building system to comply with this code. Alterations shall not create an unsafe or hazardous condition or overload existing building systems.
Alterations shall be such that the existing building or structure uses no more energy than the existing building or structure prior to the alteration. Alterations to existing buildings shall comply with Sections R503.1.1 through R503.2
The code official may approve designs of alterations which do not fully conform to all of the requirements of this code where in the opinion of the building official full compliance is physically impossible and/or economically impractical and:
The alteration improves the energy efficiency of the building; or
The alteration is energy efficient and is necessary for the health, safety, and welfare of the general public.
R503.1.1 Building envelope. Building envelope assemblies that are part of the alteration shall comply with Section R402.1.1 or R402.1.4, Sections R402.2.1 through R402.2.11, R402.3.1, R402.3.2, R402.4.3, and R402.4.4.
EXCEPTION:
The following alterations need not comply with the requirements for new construction provided the energy use of the building is not increased:
 
1. Storm windows installed over existing fenestration.
 
2. Existing ceiling, wall or floor cavities exposed during construction provided that these cavities are filled with insulation. 2 x 4 framed walls shall be insulated to a minimum of R-15 and 2 x 6 framed walls shall be insulated to a minimum of R-21.
 
3. Construction where the existing roof, wall or floor cavity is not exposed.
 
4. Roof recover.
 
5. Roofs without insulation in the cavity and where the sheathing or insulation is exposed during reroofing shall be insulated either above or below the sheathing.
 
6. Surface-applied window film installed on existing single pane fenestration assemblies to reduce solar heat gain provided the code does not require the glazing fenestration to be replaced.
R503.1.1.1 Replacement fenestration. Where some or all of an existing fenestration unit is replaced with a new fenestration product, including sash and glazing, the replacement fenestration unit shall meet the applicable requirements for U-factor and SHGC in Table R402.1.1.
R503.1.2 Heating and cooling systems. New heating, cooling and duct systems that are part of the alteration shall comply with Sections R403.1, R403.2, R403.3, and R403.6.
EXCEPTIONS:
1. Where ducts from an existing heating and cooling system are extended, duct systems with less than 40 linear feet in unconditioned spaces shall not be required to be tested in accordance with Section R403.2.2.
 
2. Existing duct systems constructed, insulated or sealed with asbestos.
R503.1.3 Service hot water systems. New service hot water systems that are part of the alteration shall comply with Section ((R403.4)) R403.5.
R503.1.4 Lighting. New lighting systems that are part of the alteration shall comply with Section R404.1.
EXCEPTION:
Alterations that replace less than 50 percent of the luminaires in a space, provided that such alterations do not increase the installed interior lighting power.
R503.2 Change in space conditioning. Any nonconditioned or low-energy space that is altered to become conditioned space shall be required to be brought into full compliance with this code.
EXCEPTION:
Where the simulated performance option in Section R405 is used to comply with this section, the annual energy use of the proposed design is permitted to be 110 percent of the annual energy use otherwise allowed by Section R405.3.