Risks Lurking Behind the Popularity of Older Detached Homes! Over 65% of Homes 31+ Years Old Suspected of Leaking Roofs
Sakura Jimusho, a real estate consulting firm, announced the results of its used detached home inspections conducted in 2025. The report highlights major defect rates in older properties, such as over 65% of homes aged 31 years or more being suspected of roof leaks, providing crucial information for potential buyers of used detached homes.
📋 Article Processing Timeline
- 📰 Published: April 7, 2026 at 19:00
- 🔍 Collected: April 7, 2026 at 10:31
- 🤖 AI Analyzed: April 21, 2026 at 00:01 (325h 30m after Collected)
“Real Estate Master Sakura Jimusho Co., Ltd.” (Shibuya-ku, Tokyo / President: Naoya Yamamoto), which provides comprehensive real estate consulting and home inspection services for individuals, and consulting services for condominium management associations, is pleased to report the compilation of defect rates for the five major items in used detached home inspections conducted by Sakura Jimusho in 2025.
[Survey Overview]
・Survey period: March 2026
・Survey organization: Sakura Jimusho Co., Ltd.
・Survey target: 1,060 used detached homes inspected by Sakura Jimusho between January and December 2025.
### [Roof Leaks]
Roof leaks tend to increase after 11 years of construction. After 11 years, the defect rate is the highest among the five items, and over 60% of homes aged 31 years or more show signs of defects.
### [Termites]
Incidents suspected of termite damage begin to be observed around 21 years of construction. When homes exceed 30 years old, incidents are confirmed in more than one in five homes.
### [Tilting]
This refers to the ratio of properties showing tilting of 6 parts per thousand or more, or overall tilting suspected of ground subsidence or differential settlement. Regarding tilting, the defect rate also begins to increase around 21 years of construction and continues to rise with age.
### [Corrosion]
This indicates the proportion of properties where corrosion is found in parts of structural materials. Similarly, after 21 years of construction, defects begin to appear in more than one in ten homes, and this inspection item's defect rate increases with age.
### [Water Leaks]
Compared to other inspection items, water leaks are more likely to be confirmed even in newer homes, with 5.6% of used detached homes up to 10 years old showing incidents. Water leaks in plumbing can be caused not only by deterioration of consumables but also by construction errors or defects at the time of new construction.
## Defect Rate of Older Properties
Composition ratio by age group of used detached houses (contracted properties) Source: East Japan Real Estate Information Organization
[Survey Overview]
・Survey period: March 2026
・Survey organization: Sakura Jimusho Co., Ltd.
・Survey target: 1,060 used detached homes inspected by Sakura Jimusho between January and December 2025.
### [Roof Leaks]
Roof leaks tend to increase after 11 years of construction. After 11 years, the defect rate is the highest among the five items, and over 60% of homes aged 31 years or more show signs of defects.
### [Termites]
Incidents suspected of termite damage begin to be observed around 21 years of construction. When homes exceed 30 years old, incidents are confirmed in more than one in five homes.
### [Tilting]
This refers to the ratio of properties showing tilting of 6 parts per thousand or more, or overall tilting suspected of ground subsidence or differential settlement. Regarding tilting, the defect rate also begins to increase around 21 years of construction and continues to rise with age.
### [Corrosion]
This indicates the proportion of properties where corrosion is found in parts of structural materials. Similarly, after 21 years of construction, defects begin to appear in more than one in ten homes, and this inspection item's defect rate increases with age.
### [Water Leaks]
Compared to other inspection items, water leaks are more likely to be confirmed even in newer homes, with 5.6% of used detached homes up to 10 years old showing incidents. Water leaks in plumbing can be caused not only by deterioration of consumables but also by construction errors or defects at the time of new construction.
## Defect Rate of Older Properties
Composition ratio by age group of used detached houses (contracted properties) Source: East Japan Real Estate Information Organization
FAQ
What is the most important thing to consider when purchasing an older single-family home?
Older single-family homes have a higher risk of potential issues such as water leakage, termite damage, tilting, corrosion, and plumbing leaks. It is important to have a home inspection by a professional before purchasing.
What are the benefits of a home inspection?
A home inspection allows you to accurately assess the current condition of the property and reduce the risk of high repair costs that may arise after purchase. It can also serve as a basis for negotiating the price with the seller.
What are the features of Sakura Office's inspection?
Sakura Office conducts home inspections from a highly impartial and fair position, providing detailed reports based on objective data. This enables buyers to confidently assess the condition of the property.