2018 Washington State Energy Code
New to the energy code? Please read this.
Our energy code team provides support to those who use the residential sections of the Washington State Energy Code (WSEC-R).
- If your building permit is submitted on or after February 1, 2021, it must meet requirements of 2018 WSEC-R. You may also need to refer to the:
- If your building permit was submitted before February 1, 2021, it must meet requirements of 2015 WSEC-R
For assistance and updates:
2018 WSEC-R Training Opportunities
Please review our webinars on residential energy code compliance and duct testing before beginning work on your permit application documents.
Questions About Commercial Portions of the WSEC?
Contact Evergreen Technology Consulting at 360-539-5300 or email com.techsupport@WAenergycodes.com. If your project is a mixed use building, please contact Evergreen prior to working on residential low-rise R2 units.
2018 WSEC-Commercial
Permit Application Documents
Please right-click the form name and save it to your computer so you can use the form's automated functions.
Options for Code Compliance
Prescriptive Method
The prescriptive path is the typical compliance approach. To follow this approach, you will need to complete a prescriptive worksheet, glazing schedule, and heating system sizing calculator.
UPDATES:
- Table R406.2 in 2018 WSEC-Residential references two tables that are provided in 2018 WSEC-Commercial: Table C403.3.2(1)C and C403.3.2(2). These tables are copied here for your convenience.
- Table 406.3, Option 2, in 2018 WSEC-Residential references section numbers in the 2018 IRC and IMC that are no longer accurate. We will update our prescriptive worksheets and the Code Compliance Calculator soon to reflect these changes. In the meantime, here are the updated section numbers:
- IRC 2015 Section M1507.3 Whole-House Mechanical Ventilation System corresponds to IRC 2018 Section M1505.4 Whole-House Mechanical Ventilation System
- IMC 2015 Section 403.8 Ventilation Systems for Group R Occupancies corresponds to IMC 2018 Section 403.4 Group R Whole-House Mechanical Ventilation System
Prescriptive Worksheets
This approach is the simplest method of WSEC code compliance. A project complies with building envelope requirements if it meets all minimum insulation levels required.
Single-Family Prescriptive Worksheet - All Climate Zones with Table 406
Multifamily Prescriptive Worksheet - All Climate Zones with Table 406
Prescriptive Checklist
The Code Compliance Calculator is useful if the prescriptive path will not work for your project. It includes the glazing schedule and the heating system sizing worksheet.
Code Compliance Calculator readme
Glazing Schedule
Using the Prescriptive Method, all glazing must have an “area weighted average” U-Factor of 0.30. This means that some windows can have a higher U-factor than 0.30 and some can have a lower U-factor than 0.30, as long as the area weighted average is U-0.30 or lower. You may need to complete this form to document glazing compliance when applying for your building permit. It is useful to have tested values when filling out this forms. NFRC AMMA provides custom U-values.
Glazing Schedule
Heating System Sizing Calculator
We recommend you use the HVAC sizing tool based on Manual J from Better Built NW.
The previous Heating System Sizing Worksheet may be useful only if you do not have cooling. This calculator assumes that your glazing products have an area weighted average of U-0.30. Choose insulation levels and enter the areas of each building component. Hover your cursor over the red triangles to see the embedded help notes. An instruction sheet is also provided.
Heating System Sizing Worksheet
Heating System Sizing Instructions
Alterations (Remodel) Worksheet
When doing a combined addition and remodel, consider using the Alteration (Remodel) Worksheet for the remodeling portion. For the addition, use the Prescriptive Path requirements for remodeling existing structures differ from requirements for new construction. No credits from Table 406.2 are required and existing buildings are not necessarily required to meet all of the requirements of the energy code. This worksheet shows what is required for your remodel.
Alterations (Remodel) Worksheet
Compliance Certificate
The certificate should be completed by the builder or other approved party and posted in the space where the furnace is located, a utility room, or another approved location in the building.
2018 WSEC Compliance Certificate
2018 Compliance Certificate - Instructions
Insulation Certificate for Residential New Construction
Insulation Certificate
Technical Assistance and Testing Resources
Duct Testers
This list of duct testers includes individuals who attended the one-day duct testing training offered by the WSU Energy Program or completed the online training, and meet the minimum requirements to test ducts for the WSEC.
Technicians who can verify that they have successfully completed duct testing training provided by the Northwest ENERGY STAR Program or Performance Tested Comfort Systems (PTCS) may also be qualified to test ducts under the WSEC.
Database of PTCS Technicians
PTCS Training
Home Energy Raters (HERS)
For information about Home Energy Raters, please see the Building Efficiency webpage.