402.1 Special Requirements for Single-Family Residential: 402.1.1
Energy Budgets: Proposed buildings designed in accordance with this section shall be designed to use no more energy from nonrenewable sources for space heating, space cooling and domestic hot water heating than a standard building whose enclosure elements and energy consuming systems are designed in accordance with section 502.2 of this Code for the appropriate climate zone, and heating system type and cooling system and whose mechanical system type is the same as the proposed building and which complies with Section 503 of this Code. Energy derived from renewable sources may be excluded from the total annual energy consumption attributed to the alternative building. 402.1.2
Calculation of Energy Consumption: The application for a building permit shall include documentation which demonstrates, using a calculation procedure as listed in Chapter 8, or an approved alternate, that the proposed building's annual space heating, space cooling and domestic hot water heating energy use does not exceed the annual space heating, space cooling and domestic hot water heating energy use of a standard building conforming to Chapter 5 of this Code for the appropriate climate zone. The total calculated annual energy consumption shall be shown in units of kWh/ft2
-yr or Btu/ft2
-yr of conditioned area. 402.1.3
Input Values: The following standardized input values shall be used in calculating annual space heating budgets:
|PARAMETER ||VALUE |
|Thermostat set point, heating |
Thermostat set point, cooling
Thermostat night set back
Thermostat night set back period
|65° F |
|Internal gain ||3000 Btu/h |
|Domestic Hot Water Heater |
|Domestic Hot Water Consumption |
|20 gallons/person/day. |
|Minimum heat storage ||Calculated using standard engineering practice for the actual building or as approved. |
Site weather data
Typical meteorological year (TMY) or ersatz TMY data for the closest appropriate TMY site or other sites as approved.
|Heating and cooling equipment |
|Equipment shall comply with Section 1411. |
The standard building shall be modeled with glazing area distributed equally among the four cardinal directions. Parameter values that may be varied by the building designer to model energy saving options include, but are not limited to, the following:
1. Overall thermal transmittance, Uo
, of building envelope or individual building components;
2. Heat storage capacity of building;
3. Glazing orientation; area; and solar heat coefficients; (where Chapter 5 does not contain SHGC requirements, the standard design shall be modeled with glazing SHGC as determined by Tables 13-1 and 13-2. SHGC values shall be determined in accordance with Section 1312.2.)
4. Heating system efficiency.
Parameter values that may not be varied:
Domestic hot water consumption. 402.1.4
Solar Shading and Access: Building designs using passive solar features with eight percent or more south facing equivalent glazing to qualify shall provide to the building official a sun chart or other approved documentation depicting actual site shading for use in calculating compliance under this section. The building shall contain at least forty-five Btu/°F for each square foot of south facing glass. 402.1.5
Infiltration: Infiltration levels used shall be set at 0.35 air changes per hour for thermal calculation purposes only. 402.1.6
Heat Pumps: The heating season performance factor (HSPF) for heat pumps shall be calculated using procedures consistent with section 5.2 of the U.S. Department of Energy Test Procedure for Central Air Conditioners, including heat pumps published in the December 27, 1979 Federal Register Vol. 44, No. 24.10 C.F.R. 430. Climate data as specified above, the proposed buildings overall thermal performance value (Btu/°F) and the standardized input assumptions specified above shall be used to model the heat pumps HSPF.
402.2 Energy Analysis: Compliance with this chapter will require an analysis of the annual energy usage, hereinafter called an annual energy analysis.
|EXCEPTION: ||Chapters 5, and 6 of this Code establish criteria for different energy-consuming and enclosure elements of the building which, will eliminate the requirement for an annual systems energy analysis while meeting the intent of this Code. |
A building designed in accordance with this chapter will be deemed as complying with this Code if the calculated annual energy consumption is 8 percent less than a similar building (defined as a "standard design") whose enclosure elements and energy-consuming systems are designed in accordance with Chapter 5.
For an alternate building design to be considered similar to a "standard design," it shall utilize the same energy source(s) for the same functions and have equal floor area and the same ratio of envelope area to floor area, environmental requirements, occupancy, climate data and usage operational schedule.
402.3 Design: The standard design, conforming to the criteria of Chapter 5 and the proposed alternative design shall be designed on a common basis as specified herein:
The comparison shall be expressed as kBtu or kWh input per square foot of conditioned floor area per year at the building site.
402.4 Analysis Procedure: The analysis of the annual energy usage of the standard and the proposed alternative building and system design shall meet the following criteria:
a. The building heating/cooling load calculation procedure used for annual energy consumption analysis shall be detailed to permit the evaluation of effect of factors specified in section 402.5.
b. The calculation procedure used to simulate the operation of the building and its service systems through a full-year operating period shall be detailed to permit the evaluation of the effect of system design, climatic factors, operational characteristics, and mechanical equipment on annual energy usage. Manufacturer's data or comparable field test data shall be used when available in the simulation of systems and equipment. The calculation procedure shall be based upon eight thousand seven hundred sixty hours of operation of the building and its service systems.
402.5 Calculation Procedure: The calculation procedure shall cover the following items:
a. Design requirements -- Environmental requirements as required in Chapter 3.
b. Climatic data -- Coincident hourly data for temperatures, solar radiation, wind and humidity of typical days in the year representing seasonal variation.
c. Building data -- Orientation, size, shape, mass, air, moisture and heat transfer characteristics.
d. Operational characteristics -- Temperature, humidity, ventilation, illumination, control mode for occupied and unoccupied hours.
e. Mechanical equipment -- Design capacity, part load profile.
f. Building loads -- Internal heat generation, lighting, equipment, number of people during occupied and unoccupied periods.
|EXCEPTION: ||Single-family residential shall comply with calculation procedures in Chapter 8, or an approved alternate. |
402.6 Documentation: Proposed alternative designs, submitted as requests for exception to the standard design criteria, shall be accompanied by an energy analysis comparison report. The report shall provide technical detail on the two building and system designs and on the data used in and resulting from the comparative analysis to verify that both the analysis and the designs meet the criteria of Chapter 4 of this Code.
[Statutory Authority: RCW 19.27A.025, 19.27A.045. 10-22-057, § 51-11-0402, filed 10/28/10, effective 1/1/11; 10-03-115, 10-13-113 and 10-22-056, § 51-11-0402, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11. Statutory Authority: RCW 19.27A.022, 19.27A.025, 19.27A.045, and chapters 19.27 and 34.05 RCW. 07-01-089, § 51-11-0402, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27A.020, 19.27A.045. 04-01-106, § 51-11-0402, filed 12/17/03, effective 7/1/04. Statutory Authority: RCW 19.27A.025 and 19.27A.045. 98-03-003, § 51-11-0402, filed 1/8/98, effective 7/1/98. Statutory Authority: Chapters 19.27, 19.27A and 34.05 RCW. 94-05-059, § 51-11-0402, filed 2/10/94, effective 4/1/94. Statutory Authority: RCW 19.27A.020 and 1990 c 2. 91-01-112, § 51-11-0402, filed 12/19/90, effective 7/1/91.]
Reviser's note: Notice of Objection: The Joint Administrative Rules Review Committee (Committee) finds that, in adopting the 2009 proposed changes to the State Energy Code, Chapter 51-11 WAC, on November 20, 2009, the State Building Code Council (Council) failed to comply with all requirements of the law and failed to adequately respond to the Committee's request for additional economic impact and cost-benefit analyses prior to adoption.
On October 1, 2009, the Committee found that the Small Business Economic Impact Statement (SBEIS) for the proposed changes filed with the Code Reviser failed to comply with all requirements of law. The Committee requested that the Council conduct a cost-benefit analysis pursuant to RCW 34.05.328 and amend the SBEIS to provide additional economic impact information, including an estimate of the number of jobs that would be created or lost as a result of compliance with all the proposed rules, as required by RCW 19.85.040 (2)(d).
The Council provided the Committee with information and data on November 18, 2009. On December 2, 2009, the Committee found that the Council failed to adequately respond to the Committee's request for additional data. Specifically, the Committee found that the Council failed to amend the SBEIS to (a) estimate the number of jobs that would be created or lost as a result of compliance with the proposed changes; and (b) support the SBEIS with a detailed and rigorous costs analysis of the cumulative impact of all the changes. In addition, the Committee found that the Council failed to provide the Committee with a cost-benefit analysis of the proposed changes and pursuant to the requirements of RCW 34.05.328.
The Committee strongly supports a process that makes thoughtful and informed progress towards changes that result in improved energy efficiency in our buildings, wherever practicable. While the Council worked diligently, it is the opinion of the Committee that the Council did not fully develop and consider the economic impacts and costs versus benefits of these significant changes to our Energy Code. Furthermore, it is the opinion of the Committee that the Council and the Legislature need this information to fully evaluate the value, impacts, and consequences of the proposed codes, with due diligence to their respective fiduciary responsibilities, in order to create the best informed public policy.
As a result, the Committee recommends that the Governor suspend the adoption and implementation of the changes to the Energy Code, Chapter 51-11 WAC, adopted by the Council on November 20, 2009, until such time as a more adequate analysis has been completed and considered by the appropriate bodies.
For all of the above stated reasons, the Committee objects to the changes to the State Energy Code, Chapter 51-11 WAC, that were adopted by the Council on November 20, 2009, and hereby directs the Code Reviser, pursuant to RCW 34.05.640(4), to publish this Notice of Objection in the Washington State Register and along with any publication in the Washington Administrative Code of changes to Chapter 51-11 WAC that were adopted by the Council in 2009 and filed with the Code Reviser.