Energy Code

What It Is

The 2018 Washington State Energy Code (AMC 15.04) regulates the energy-use features of new and remodeled buildings, including:

  • Building Envelope: requirements for roofs, walls, window's etc. to control heat loss and air leakage 
  • Heating, Ventilation and Air Conditioning (HVAC): efficiency for heating and cooling equipment
  • Lighting: number and type of lighting fixtures and controls
  • Metering, plug load controls, transformers, motors, and renewable energy
  • Water Heating: equipment efficiency and controls

Aberdeen has adopted by reference, the 2018 Washington State Energy Code, as written by the Washington State Building Code Council and filed as Chapter 51 to 11 Washington Administrative Code.

Energy Code Worksheets for residential projects

Forms and worksheets for the 2018 WSEC have changed. Instead of being group into one workbook, the Prescriptive Worksheet, Glazing Schedule, and Heating System Sizing Calculator are now independent documents. If you have trouble using any of these worksheets, view the webinar in the Presentations and Videos section of this page, which explains how to complete these worksheets.

Prescriptive Method. 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 for the applicable climate zone. This Excel file provides a method for documenting compliance with the prescriptive standards.

Prescriptive Worksheet – All Climate Zones

Table R406.2 2018 Energy Credits

2018 Prescriptive Energy Code Checklist

Suggested Option Combinations: This document contains combinations of options from Table 406.2 to achieve 3.5 credits which is the amount needed for an average size house in Washington (1,500 to 5,000 square feet). There are numerous other combinations available but the following utilize readily available equipment and/or some minor upgrades to the building envelope.

Energy Credit Option Combinations

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.

Glazing Schedule

Heating System Sizing Calculator: This calculator - a simpler version of previous worksheets for newly constructed buildings - assumes that your glazing products have an area weighted average of U-0.30. Use the dropdown boxes to choose insulation levels and enter the areas of each building component. The form has embedded instructions; hover your cursor over the red triangles to see the help notes. This calculator sizes heating systems only; it will not accurately size cooling systems.

Heating System Sizing Worksheet

Total UA Alternative Worksheet (formerly Component Performance): The Total UA Alternative worksheet has been updated to provide the user with error prompts when information is incorrect or missing. If you are having trouble using the worksheet, view the webinar under the Presentations and Videos section of this page, which explains how to complete the worksheet.

Total UA Alternative Worksheet

Alterations: Requirements for alterations or remodels of existing structures differ from the 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 will show what is required for your remodel and may be filled out using Excel or by hand.

Alterations (Remodel) Worksheet

Recent Changes

None at this time.


View the permit program for more information.

Contact Information

  • For additional information on requirements Email Josh Pagett or call 360-537-3221.
  • For information on permit submittal requirements and pricing contact the Permit Technician at 360-537-3217.