What’s New in the 2025 BC Building Code? [Effective March 10, 2025]

Sungsu Kang
Jun 25, 2025
2 min read

The 2025 updates to the BC Building Code (BCBC) are some of the most impactful changes in recent years—especially for designers, builders, and homeowners involved in residential construction or renovation. These updates officially take effect on March 10, 2025, and compliance is mandatory for all permit applications submitted on or after this date.

Let’s break down the key changes and what they mean for you.

🏗️ 1. Enhanced Seismic Design Requirements (Section 9.23)

The updated BCBC introduces significantly more stringent seismic bracing standards for buildings under Part 9 (typically residential low-rise).

Key Points:

Braced-wall bands and lateral load paths must now be clearly documented.
Section 9.23.13 has been overhauled to improve performance during earthquakes and wind events.
In most cases, a structural engineer's seal will be required to validate bracing layout and methodology—even in low-seismic regions.

✅ Tip for Designers: Start integrating bracing details into your permit drawing sets and coordinate early with structural consultants.

🚻 2. Adaptable Dwelling Units (ADUs) Become Mandatory

New accessibility requirements are in place to improve livability for people of all ages and abilities.

What’s Changing:

All new homes (including detached, townhouses, and suites) must have reinforced bathroom walls for grab bar installations.
Larger multi-unit buildings must now include at least 20% adaptable units instead of the prior 100% rule.
For low-rise residential buildings, first-floor units must include adaptable features, even in walk-up designs.

✅ Designers & Builders: Make sure bathroom framing includes blocking at toilet and tub locations.

🌱 3. Zero Carbon Step Code (ZCSC) – Level 1 Now Required

This is a major milestone for BC’s decarbonization efforts. As of March 2025, all new buildings must comply with ZCSC Level 1, even if you're not building to Passive House or Net Zero standards.

What This Means:

Operational GHG emissions must be tracked and reported.
On prescriptive (non-performance) paths, builders must disclose fuel types and energy systems (e.g., gas, heat pump, electric baseboard).
This requirement applies to both Part 3 and Part 9 construction.

✅ Energy Advisors & Builders: Be prepared to collect and submit emissions data alongside EnerGuide or Step Code modeling.

📋 Summary of 2025 BCBC Changes

Area	Update Summary
Seismic Bracing	Stronger lateral load requirements + sealed structural plans
Adaptable Dwellings	Mandatory grab bar walls + 20% adaptable unit inclusion
Zero Carbon Step Code	Minimum EL-1 (GHG disclosure and tracking) now required

🔧 What Should You Do Now?

Update your drawing templates to include seismic and ADU elements.
Coordinate with engineers for sealed structural layouts.
Use the latest EnerGuide or Step Code tools to meet GHG tracking requirements.
Inform clients early, especially developers and homeowners planning 2025 submissions.

💬 Final Word

The 2025 BC Building Code reflects BC’s push toward safer, more accessible, and low-carbon construction. Whether you’re a designer, drafter, builder, or consultant, staying ahead of these updates will keep your projects compliant and clients happy.

📩 Need help updating your drawing sets or workflows for the new BCBC? Contact us for a free consultation.