How Will Seismic Evaluation Scores Change Under the Revised Standards? Integral Releases Verification Results for the 2025 Revised Edition

Integral Co., Ltd. (Tsukuba City, Ibaraki Prefecture, 2-7 Gakuenminami; President: Akemi Fujima), developer and distributor of the seismic assessment and reinforcement design software 'Homeskun Seishin Diagnostic Pro' for wooden houses, held the 'Comprehensive Explanation Seminar on the 2025 Revised Edition: Seismic Assessment and Reinforcement Methods for Wooden Houses' on July 1, 2026, at KFC Hall & Rooms in Ryogoku, Tokyo.

The '2025 Revised Edition: Seismic Assessment and Reinforcement Methods for Wooden Houses' (published by the Japan Building Disaster Prevention Association, designated by the Minister of Land, Infrastructure, Transport and Tourism as the Seismic Retrofit Support Center) was released on January 30, 2026. This 2025 revision, the first major update in 13 years since the 2012 edition, incorporates knowledge gained since 2012 and refines diagnostic methods—including general and detailed assessments—with enhanced explanations. It also aligns with the revised Building Standards Law, effective April 2025, particularly regarding required wall quantity regulations.

In response to the release of this revised edition, Integral conducted various verifications using the 2025 revised diagnostic methods and presented the results at this seminar. For example, compared to the 2012 edition, both general and detailed diagnostic methods showed a tendency for lower evaluation scores, with differences of 0.14 to 0.25 points observed depending on calculation methods and building conditions. The company highlighted that buildings significantly affected by semi-shear walls, eccentricity evaluation, or wall deterioration reduction should be assessed and reinforced under the 2025 revised standards.

Presentation of Analysis Results: New vs. Old (2025 Revised vs. 2012 Edition)

At this seminar, Integral presented the results of its comparative analysis between the 2025 revised edition and the 2012 edition.

Integral's analysis confirmed that required seismic resistance is either similar or slightly reduced, due to refined building weight calculations and the elimination of short-side wall quantity increases. Meanwhile, available seismic resistance generally showed a decreasing trend, influenced by revised (relaxed) reduction coefficients for column connections, stricter evaluations of wall deterioration, and stricter opening assessments. A significant increase was observed on the second floor. As a result, upper structure evaluation scores tend to decrease under both general and detailed diagnostic methods, with maximum reductions of 0.14 in general diagnosis and 0.25 in detailed diagnosis.

These are preliminary results based on the beta version of 'Homeskun Seishin Diagnostic Pro Ver.6.0' currently under development by Integral. The company plans to conduct further detailed verification in the future.

Key Topics Covered in the Seminar

- Key updates in the general diagnostic method

- Key updates in the detailed diagnostic method

- Comparison of evaluation scores between the 2012 and 2025 editions (general diagnostic method) - Comparison of evaluation scores between the 2012 and 2025 editions (detailed diagnostic method) - Comparison between general and detailed diagnostic methods in the 2025 edition - Changes in on-site inspection items

High Interest in the 2025 Revision: Attention from Municipalities and Architectural Firms

After the seminar, many participants expressed interest in incorporating the 2025 revised edition into their future work.

<Excerpts from Participant Feedback>

'I was surprised to see how much evaluation scores can vary—more than I expected. The results presented with various graphs were easy to understand, and I now clearly grasp the intent behind the revision. I’d like to re-evaluate buildings I’ve previously assessed.'

'I was able to confirm the revised content, its intentions, and the extent of its impact. Earthquakes of intensity 6 or higher have occurred across Japan. To create homes that are safe and secure—not just avoiding collapse but enabling continued living—I want to base my work on the 2025 revised edition for seismic reinforcement.'

The fact that both the Tokyo and Osaka seminar venues filled up shortly after registration opened also indicates high interest among professionals regarding the 2025 revised edition.

Furthermore, officials from municipalities and associations of architectural firms have requested similar seminars, and Integral plans to actively respond to such demands in the future.

Seminar Also Held in Osaka on July 15 (Fully Booked)

Integral will also hold this seminar in Osaka on July 15, 2026.

The Osaka venue is already fully booked, and only waitlist registrations are currently being accepted.

<Seminar Details>

https://seminar.homeskun.jp/seminar_info.php?id=20260701

'Seishin Diagnostic Pro Ver.6.0' Compatible with 2025 Revised Edition to Be Released by End of July

Integral plans to release 'Homeskun Seishin Diagnostic Pro Ver.6.0,' compatible with the 2025 revised edition, by the end of July 2026. Detailed product information will be announced later on the official Homeskun website and other channels.

<Homeskun Official Website>

https://www.homeskun.com/

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[Company Overview]

Integral Co., Ltd. develops and sells the 'Homeskun' series of software, including 'Homeskun Seishin Diagnostic Pro,' which supports structural calculations, seismic assessments, and energy-efficient design. Based in Tsukuba City, Ibaraki Prefecture, the company combines architectural expertise with IT to provide products and services that enhance efficiency and quality in design and diagnostic work.

Company Name: Integral Co., Ltd. Headquarters: 2-7 Gakuenminami, Tsukuba City, Ibaraki Prefecture URL: https://www.integral.co.jp/

Homeskun Official Website: https://www.homeskun.com/