Japan’s Recent Building Code Revisions

Overview of Japan’s Recent Building Code Changes


Building Standards for a Greener Future: Key Changes in Japan’s Building Code

In 2024, Japan updated its Building Standards Act to improve how buildings use energy. This change supports Japan’s goal of a carbon-neutral society. Let’s look at the main changes and how they will affect building practices.

1. Changes to the Housing Performance Evaluation System

The Housing Performance Evaluation System now matches the Building Standards Act more closely. Key updates include changes in how wall quantities are measured. Additionally, the new rules consider local factors like snow load and earthquake risks. As a result, these updates help ensure buildings are safer and better suited to their locations.

2. Updates to the Long-Term Superior Housing Certification System

The standards for long-term housing have also been raised. Previously, the focus was mainly on earthquake safety at levels 2 or 3. Now, homes must also meet Zero Energy House (ZEH) standards. Consequently, this update aims to create more energy-saving and eco-friendly homes.

3. Transitional Measures

To help with the transition to the new rules, there is a one-year grace period. During this time, designs that follow the old standards are still allowed if noted in the application. This period is particularly helpful when design changes are difficult or need more time.

4. Simplified Structural Calculations

The code also updates how builders calculate structure safety, especially for wooden buildings. Specifically, changes include the size of columns and the types of bracing allowed. Furthermore, the new methods ensure buildings can handle actual loads, making construction safer.


In summary, these changes are meant to make buildings more energy-efficient and stronger in earthquakes. They also help Japan move toward a carbon-neutral future. As a result, buildings that follow the new rules will use less energy and be safer in disasters, thus supporting a more sustainable environment.

In summary, these changes are meant to make buildings more energy-efficient and stronger in earthquakes. They also help Japan move toward a carbon-neutral future. As a result, buildings that follow the new rules will use less energy and be safer in disasters, thus supporting a more sustainable environment.