Open House Architect Expands General Contracting Business into Kansai; Starts Construction on Three Apartment Buildings

Open House Architect Co., Ltd. (Headquarters: Nakano-ku, Tokyo; President: Mitsuo Nagai; hereinafter "Open House Architect") has established a new base for its general contracting division in the Kansai region, following its timber construction business, and has begun construction of apartment buildings in the area.

Between Friday, June 5, 2026, and Wednesday, June 10, 2026, the company commenced construction on a total of three apartment buildings. In the Kansai area, the company aims to contribute to local housing development and create high-quality homes together with skilled local partner companies.

Entry into the Kansai Apartment Market The apartment market in Kansai (Kinki region) continues to see strong demand, with average prices and prices per square meter reaching record highs. However, the environment surrounding apartment construction is becoming increasingly difficult, and balancing construction timelines and quality maintenance with appropriate cost management is the biggest challenge for developers.

In this context, Open House Architect's general contracting business leverages a solid construction system that combines experience and know-how cultivated in the timber construction business with engineers who have extensive experience from major and mid-tier general contractors. By flexibly responding to customer needs, from high-grade RC rental/condominium apartments to large-scale projects, the company has received numerous repeat orders.

Given the recent increase in inquiries and requests for quotes from major and quasi-major developers nationwide, the company decided to expand into the Kansai region. At the three construction sites that have now begun, the company will sincerely engage with each step of the process and build strong partnerships with local communities to develop sustainable apartment construction.

Strengths and Growth Strategy of Open House Architect's General Contracting Business Since entering the general contracting business in 2016, Open House Architect has received numerous orders, mainly from major clients, and has continued to grow rapidly. The general contracting business alone achieved sales of 36.5 billion yen in fiscal year 2025, recording a growth rate significantly higher than the industry average. Building on this solid business foundation and trust, the company will provide "Sincere Quality" in the Kansai region as well.

・Balancing Excellent Cost Performance and High Quality Rational construction know-how cultivated in the timber construction business is applied to the general contracting business. By combining thorough cost management through Value Engineering (VE) and solid design and technical capabilities capable of handling high-rise RC and S-frame construction, the company achieves buildings with high asset value.

・Technical Exchange and Quality Improvement with Partner Companies Through "Kyojinkai," a co-creation system with partner companies, the company ensures technical exchange and safety quality management. It conducts patrols based on annual safety and health management plans and risk assessments through monthly safety and health council meetings. Beyond simple ordering relationships, the company builds strong on-site capabilities by continuing to pursue high quality together with local artisans.

・"On-site Visualization" and Safety Quality through DX Using a proprietary core system, administrative tasks such as ordering and billing have been completely digitized, promoting overwhelming operational efficiency. On-site, in addition to real-time video sharing, the company has introduced the latest technologies, such as AI-assisted inspections and automated minute-taking. By simultaneously advancing the "visualization" and "automation" of on-site management, the company ensures thorough construction management.

*For companies and individuals interested in the expansion of the general contracting business in Kansai after reading this announcement:

Following the opening of the base, the company is recruiting partner companies to work together to create high-quality homes in the Kansai area, as well as project members to take on the launch of the business in Kansai.

Please check the following for details.

- Partner Recruitment Page: https://oha.openhouse-group.com/joinus/partner/ - "General Contracting Kansai Base Launch Member Recruitment" Special Page: https://oha.openhouse-group.com/recruit/construction-kansai/

About Open House Architect As part of the Open House Group, Open House Architect is a comprehensive construction firm that handles both "timber detached houses" and "apartment construction," which is rare in the industry. With strengths in building high-quality, reasonably priced homes, the company has expanded its supply from the Tokyo metropolitan area to Nagoya, Kansai, and Fukuoka. It boasts a track record of approximately 56,000 completed buildings to date and has earned deep trust from both inside and outside the group. To exceed the expectations of customers, the industry, and society, the company aims to bring innovation to the world of architecture together with its employees and partners.