Understanding the Top 10 Changes in the 2021 Washington State Building Codes
The 2021 Washington State Building Codes officially went into effect on March 15, 2024, after years of delays due to litigation. While the legal battles continue, these new regulations are now in place. Here’s a detailed look at the top 10 changes and what they mean for both builders and homeowners in Washington State.
1. Natural Gas: The new codes discourage the use of natural gas for space and water heating in new homes, leading to significantly higher compliance costs compared to electric options. Homeowners planning renovations should note that existing gas appliances can only be replaced with equivalent units, maintaining the same heating capacity.
2. Energy Code Credits: The number of energy credits required for new homes has increased:
- Small homes (<1,500 sq. ft.): 5 credits
- Medium homes (1,500-4,999 sq. ft.): 8 credits
- Large homes (5,000+ sq. ft.): 9 credits
- Additions (150-500 sq. ft.): 2 credits
- Group R-2: 6.5 credits
- Small additions (<150 sq. ft.): Exempt
3. Continuous Insulation: Continuous insulation is now a requirement if following prescriptive code standards. However, by using the C3 calculator to demonstrate a reduction in total UA, homeowners can potentially avoid this requirement.
4. Small Additions: Additions under 150 square feet no longer need to earn additional energy credits. This makes it easier for homeowners to add small spaces like walk-in closets without facing significant regulatory hurdles.
5. Air Leakage: The allowable air leakage rate has been reduced to 4 ACH, which improves energy efficiency but requires careful planning and execution by builders to achieve.
6. EV Charging: New homes with attached garages or carports must now include pre-wiring for electric vehicle (EV) charging. This involves installing a 40-amp dedicated 208/240-volt branch circuit, making it easier for homeowners to add EV charging stations in the future.
7. Lofts: Lofts are now classified as mezzanines rather than habitable attics. This change allows for lower ceiling heights and more flexible use of loft spaces, providing homeowners with more design options.
8. Existing Buildings and Structures: The revised code, now located in Chapter 45, offers more flexibility for repairs, alterations, additions, and relocations. This helps homeowners make changes to existing structures more easily and cost-effectively.
9. Radon: In high-radon areas, new testing requirements mandate achieving a radon level of 4 pCi/L or lower. Homeowners in these areas will need to plan for mitigation measures and retesting to meet these standards.
10. Kitchen Exhaust Rates: The required airflow rates for kitchen exhaust systems have increased:
- Electric ranges: Minimum 160 CFM
- Combustion ranges: Minimum 250 CFM These changes aim to improve indoor air quality and align with updated health standards.
The 2021 Washington State Building Codes bring significant changes that affect both new construction and renovations. Homeowners and builders alike must stay informed and work with qualified professionals to ensure compliance with these new standards.
For detailed guidance and compliance support, consult with industry experts and visit the BIAW website for more information. Stay updated on the ongoing litigation and its potential impact on these new codes.
This revised version includes information relevant to both homeowners and builders, ensuring that everyone affected by the new building codes can understand and comply with the changes.