What Iida Sangyo does

Iida Sangyo Co., Ltd. (株式会社飯田産業) is a Japanese residential real estate developer specializing in the design, construction, and sale of newly built detached houses, operating as a core subsidiary of Iida Group Holdings — Japan's largest detached house developer. Founded on July 8, 1977 and headquartered in Musashino City, Tokyo, the company sells its homes under the Heartful Town brand through a direct-sales network of 107 sales offices across Japan, reporting ¥295 billion in revenue, 6,897 detached house sales, and approximately 250 condominium sales for the fiscal year ending March 2026.

The company's core technology is the proprietary I.D.S. (Intelligent Design System) construction method, a wooden framework-panel system that combines design flexibility with government-certified Grade 3 earthquake resistance (highest available rating), supported by patented T Lock II structural fittings and proprietary bearing wall panels with the highest government wall ratio of 5.0. Iida Sangyo also offers SI (Skeleton Infill) housing designed for 70-90 year lifespans with flexible interior modification to accommodate family life cycle changes. The vertically integrated business model covers land acquisition, design, construction, sales, and after-sales service, with a 30-year structural warranty available and an in-house reform/renovation service for installed homes.

The company generates revenue primarily through one-time property sales transactions to individual home buyers — Japanese families seeking detached housing with earthquake resistance and long-term durability — supplemented by condominium sales, custom home construction via Universal Home, resort/hospitality operations (Seawood HOTEL, Enoshima Hotel/Spa, EastWood Country Club), renovation services, and overseas housing operations in Indonesia and Russia. The company delisted from the Tokyo Stock Exchange in 2013 upon formation of the Iida Group Holdings conglomerate and currently operates as a wholly-owned subsidiary with 2,006 group employees.

Name

Iida Sangyo

Legal name

Iida Sangyo Co., Ltd.

Website

https://iidasangyo.co.jp

Company type

Private

Founded year

1977

Operating status

Operating

Headcount range

1,001–5,000 employees

Short description

Iida Sangyo is a Japanese residential developer and core subsidiary of Iida Group Holdings that designs, builds, and sells newly built detached houses (Heartful Town brand) and condominiums through 107 direct sales offices across Japan, serving individual families seeking earthquake-resistant, long-lifespan housing.

Ownership category

akta.pro rank

Product category

Residential Real Estate Development

NAICS

New Housing For-Sale Builders (236117), New Multifamily Housing Construction (except For-Sale Builders) (236116), Residential Remodelers (236118)

SIC

General Bldg Contractors - Residential Bldgs (1520), Land Subdividers & Developers (No Cemeteries) (6552), Hotels, Rooming Houses, Camps & Other Lodging Places (7000)

akta.pro primary industry

Spec Home / Production Homebuilding (Tract & Volume Builders) (IMAFABAD)

akta.pro secondary industries

Residential Land Development & Subdivision Homebuilding (Build-to-Sell Communities) (IMAFABAL), Residential Design-Build & Renovation-Integrated Builders (IMAFABAE)

Keywords

• Detached house sales
• Residential real estate development
• Home construction services
• Property development
• Home renovation services

Headquarters

HQ city

Musashino

HQ country

Japan

HQ region

Asia

Offices9 records

Markets served

GTM type

B2C

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Personnel, Operations, Marketing or Sales, Infrastructure, Technology or R&D

Revenue model

1. New Detached House Sales (新房一戸建事業): Core business selling newly constructed detached houses (Heartful Town series). The company acquires land, develops properties, designs, constructs, and sells homes directly to consumers. Revenue is generated through one-time property sales transactions.
2. New Condominium Sales (新房マンション事業): Development and sales of newly built condominiums as part of the residential property portfolio.
3. Custom Home Sales (房地产业): Bespoke custom home construction services for individual customers, working with Universal Home brand.
4. Reform/Renovation Services (リフォーム事業): Home renovation and remodeling services for existing properties, including kitchen, bathroom, exterior, and structural modifications.
5. Resort/Hospitality (リゾー卜事業): Hotel and resort operations including Seawood HOTEL (Miyako Island), Enoshima Island Spa/Hotel, EastWood Country Club, and travel services.
6. Overseas Business (海外事業): International residential development operations in Indonesia and Russia, applying Japanese construction quality standards to overseas markets.

Pricing tiers

Go-to-market motion1 record

Distribution channels5 records

Marketing channels6 records

Core offering

Iida Sangyo develops, constructs, and sells newly built detached houses (under the Heartful Town brand) and condominiums directly to individual home buyers in Japan. The company also provides renovation/reform services for existing homes, operates resort hotels and a country club, and runs international housing development projects in Indonesia and Russia, leveraging its proprietary I.D.S. earthquake-resistant construction method throughout.

Product overview

Iida Sangyo is a real estate developer specializing in new detached houses (建売住宅) and condominiums, operating as a core company of the Iida Group Holdings (飯田グループホールディングス). The company operates a vertically integrated business model covering land acquisition, design, construction, sales, and after-sales service. Core products include the ハートフルetown (Heartful Town) branded detached houses and 新築マンション (new condominiums). The portfolio includes complementary services such as いいだのリフォーム (renovation), 飯田産業アプリ (mobile property search app), トラベルサービス (travel services), and resort hotel operations including シーウッドホテル, 江の島ホテル, and 江の島アイランドスパ. The company also operates internationally with housing businesses in Indonesia and Russia. In 2026, the company reported annual detached house sales of 6,897 units, apartment sales of approximately 250 units, 107 sales offices, 2,006 employees, and 295 billion yen in revenue.

Differentiator

Problem solved

Functional benefit

Brands

• Heartful Town (ハートフルタウン): Brand name for Iida Sangyo's new detached houses featuring earthquake-resistant construction and SI housing design
• I.D.S. Construction Method
• Iida Resorts (いいだリゾーつ)

Products and services

• Heartful Town (ハートフルタウン) - New Detached House Business (新築一戸建て事業)

Quantifiable outcome

• Highest earthquake resistance Grade 3 achieved in Housing Performance Indication System
• +2 more outcomes

Named customers3 records

Segments3 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

Four partnerships are on record, tiered parent company and core.

• 飯田グループホールディングス株式会社 (Iida Group Holdings Co., Ltd.)parent companyOthersListed parent company (stock code 3291) on Tokyo Stock Exchange. Iida Sangyo is a core operating subsidiary contributing to the Iida Group's position as Japan's largest detached house developer with over 40,000 annual unit sales group-wide.
• 一建設株式会社, 株式会社東栄住宅, タクトホーム株式会社, 株式会社アーネストワン, アイディホーム株式会社 (Iida Group Companies)coreOthersSix companies integrated under Iida Group Holdings in November 2013, including Iida Sangyo, to form Japan's largest detached house development group.
• PT.Perumnas Iida Group (Indonesia)coreStrategic or Co-development PartnerOverseas subsidiary established October 2017 in Jakarta, Indonesia. Provides Japanese-quality earthquake-resistant housing adapted to local culture and climate.
• Little Tokyo Project (Russia/Tatarstan)coreStrategic or Co-development PartnerDetached house and custom home project in Tatarstan Republic, Russia, started November 2016. Uses Japanese construction methods adapted for local climate with foundation engineering.

Scale indicators7 records

Recent moves10 records

Expansion highlights6 records

Direct peers

• Daiwa House Industry: Japan's largest homebuilder and a direct competitor across the entire residential housing spectrum, including detached for-sale homes, custom homes, and condominiums. Competes with Iida Sangyo in the spec/build-to-sell detached segment and shares a national distribution footprint.
• Sekisui House: Major Japanese homebuilder with substantial detached housing and custom home operations. Directly competes with Iida Sangyo in the for-sale detached housing market, with overlapping earthquake-resistant technology positioning and similar buyer demographics.
• Open House Group: Tokyo-focused spec home builder with strong metropolitan detached housing operations. Directly comparable to Iida Sangyo in the urban Tokyo market for first-time home buyers and upgrade buyers moving from apartments to detached homes.
• Tama Home: Japanese spec home builder specializing in low-cost detached for-sale housing, closely comparable to Iida Sangyo's Heartful Town brand. Both compete in the affordable 3LDK detached segment with similar price points (¥30-45M range) and buyer profiles.
• Panasonic Homes: Major Japanese homebuilder owned by Panasonic, operating in custom and spec detached housing with proprietary construction methods. Competes with Iida Sangyo in the tech-forward, earthquake-resistant detached housing segment.
• Sumitomo Realty & Development: Diversified real estate developer with significant detached housing, condominium, and remodeling operations. Competes with Iida Sangyo in Tokyo metropolitan detached for-sale housing and shares exposure to land acquisition and construction cost dynamics.
• Mitsui Home: Custom and spec home builder operating under Mitsui Group affiliation, with proprietary construction technology and earthquake-resistant positioning. Directly competes with Iida Sangyo's Universal Home custom brand and Heartful Town spec brand.
• Asahi Kasei Homes: Homebuilder subsidiary of Asahi Kasei Group focused on custom and spec detached housing with proprietary long-life housing technology. Comparable to Iida Sangyo's I.D.S. method positioning around durability and earthquake resistance.

Emerging players

• Tokyu Land Corporation: Diversified real estate developer with growing detached housing operations, particularly in the Tokyo metropolitan area. Represents an emerging competitive threat in Iida Sangyo's core Kanto region market.

Broad incumbents

• Haseko Corporation: Major Japanese construction and real estate developer with condominium and detached housing operations. While primarily a multifamily builder, Haseko's for-sale housing division competes with Iida Sangyo's offerings and shares similar Tokyo metropolitan customer base.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks5 records

Key highlights6 records

Customer concentration

• YouTubeyoutube.com/@iidasangyo_1977_official
• Instagraminstagram.com/iidasangyo_1977_official

Compliance2 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles10 records

Subsidiaries4 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Iida Sangyo