Our Concept

We would like to express our heartfelt condolences to those who lost their lives in the 2024 Noto Peninsula Earthquake, which struck on January 1, 2024, and extend our deepest sympathies to everyone affected by the disaster.

Even Toyama Prefecture, where our institute is located, experienced unprecedented intense shaking.
Among the houses in Toyama that have undergone seismic retrofitting through our institute, no structural damage was observed. The reinforced walls we installed effectively absorbed the earthquake’s tremors.
In light of the destruction caused by the collapse of earthquake-vulnerable buildings, we are once again reminded of the critical importance of seismic retrofitting.

Many lives were also lost due to the collapse of wooden homes during past disasters, such as the Great Hanshin-Awaji Earthquake and the Kumamoto Earthquake.
It is reported that 90% of fatalities during the Hanshin-Awaji Earthquake were caused by building collapse, and 90% of those occurred within the first 15 minutes after the quake.
In the case of the Kumamoto Earthquake, structural damage was heavily concentrated in older wooden homes built before the 1981 building code revisions.

The Japanese government established the Headquarters for Earthquake Research Promotion to investigate where and what types of earthquakes are likely to occur.
According to these studies, there are several active fault lines in Toyama Prefecture.
For example, a 2021 survey designated the Tonami Plain Fault Zone and the Kurehayama Fault Zone as "S-Rank," meaning the probability of a major earthquake occurring within 30 years exceeds 3%—a level comparable to, or even higher than, that of the Hanshin and Kumamoto earthquakes.
Based on these findings, the Toyama Prefectural Disaster and Crisis Management Division has conducted damage projections.
In the event of a major quake along the Kurehayama Fault Zone, it is estimated that 90,424 buildings could be completely destroyed and 4,274 people could lose their lives.

Toyama Prefecture is currently promoting seismic retrofitting of homes.
Out of 379,800 homes (as of 2013), approximately 105,300—or 28%—are considered structurally inadequate.
The goal is to reduce this number to about 35,000 by 2025, effectively upgrading around 70,000 homes.

However, progress has been slow.
Only 42 homes received subsidies for retrofitting in fiscal year 2022, and only 454 homes have been retrofitted over the past 18 years (an average of 25 per year).
From fiscal year 2025, Toyama Prefecture and its municipalities plan to increase retrofit subsidies to 1.4 million yen, signaling a more proactive approach.
Some local governments even provide additional grants for seismic-related renovation work.

Based on our analysis, the reasons for the slow progress include:

1. A lack of awareness about earthquake risk due to the absence of recent major quakes in Toyama
2. Larger floor areas and traditional layouts with few walls (e.g., rooms with sliding paper doors), which increase renovation costs
3. A shortage of specialists capable of handling all aspects of the process—from assessment to design, construction, and subsidy application—for older wooden homes

In response to this situation, we established the Institute for Seismic Retrofit of Wooden Houses, which specializes in addressing these challenges.
We are professionals with deep knowledge of the unique architectural features of homes in Toyama Prefecture.

Our Mission

1. We aim to provide seismic retrofitting that meets essential safety standards with minimal cost.
2. From initial assessment to design and construction, we offer comprehensive support with a client-centered approach.
3. We also assist with subsidy applications, tax deductions, and securing loans to minimize the burden on homeowners.

Our Approach

We provide an integrated service for wooden homes, covering seismic assessment, retrofit design, subsidy application, and construction.
So far, we have completed 137 assessments and 45 retrofitting projects.
The average floor area of these homes is 194m² (59 tsubo), with an average retrofit cost of 2.33 million yen.
This equates to about 12,000 yen per square meter, including design, construction supervision, and subsidy processing.
On average, clients receive 1.04 million yen in subsidies and pay 1.29 million yen out-of-pocket.
Additional financial benefits include income tax reductions and property tax deductions (available if the building achieves a seismic index Iw ≥ 1.0).

Due to rising labor and material costs in recent years, the current expected cost is approximately 13,000 to 20,000 yen per square meter.

For Homeowners

Seismic diagnosis, design, retrofitting, and subsidy applications can be technically complex and difficult to understand.
We clearly explain each step in the process, enabling homeowners to proceed with confidence.
We also provide design plans and cost estimates at the time of diagnosis, allowing for immediate evaluation of retrofit options.

In addition to seismic retrofitting, we can combine related upgrades—such as energy efficiency improvements and barrier-free modifications—that qualify for additional subsidies.

Clients appreciate our detailed explanations using renovation photos and hand-drawn sketches, as well as our on-site supervision, which provides clarity and assurance about the work being done.

Services Tailored to Homes in Toyama Prefecture

We provide seismic retrofitting specifically designed for the unique characteristics of detached houses in Toyama Prefecture.

Characteristics of Homes in Toyama

• Large floor areas
• Two adjoining Japanese-style rooms (washitsu)
• Traditional engawa (veranda) attached to washitsu
• Many openings on the east and south sides
• Engawa often lacks a foundation

▶︎ See our Institute Column for a detailed explanation.

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Office Overview

Qualifications

Memberships

• Toyama Association of Architectural Design Firms
• Toyama Association of Architects
• Interior Coordinator Club TOYAMA