Watahan Solutions Co., Ltd. Contributes to a Decarbonized Society with Two Environmentally Friendly Car Park Orders and Commencements, Utilizing New Certification for 'TSC295' Cold-Formed Square Steel Pipes Made from Electric Arc Furnace Steel

Watahan Solutions Co., Ltd. (Headquarters: Shinjuku-ku, Tokyo; Representative Director and CEO: Isamu Nohara; hereinafter "the Company") announces that it has newly acquired fire-resistance ministerial certification for self-propelled car parks utilizing cold-formed square steel pipes (commonly known as "TSC295") made from electric arc furnace steel plates, developed and supplied by Tokyo Steel Co., Ltd. (Headquarters: Chiyoda-ku, Tokyo). We have now received orders and commenced construction for two self-propelled car parks using this certification.

TSC295 is a cold-formed square steel pipe developed by Tokyo Steel Co., Ltd. and certified by the Minister of Land, Infrastructure, Transport and Tourism. As electric arc furnace steel (recycled steel products) primarily uses scrap as a raw material, it can reduce carbon dioxide emissions per ton of crude steel to about one-fifth compared to blast furnace steel.

The Company has newly acquired fire-resistance certification by incorporating TSC295, which was previously difficult to adopt, as a usable material into specifications based on the fire-resistance ministerial certification standards.

Furthermore, by using electric arc furnace steel not only for H-section beams based on JIS standards but also for columns, which was a challenge in the past, we will strive to further reduce carbon dioxide emissions and contribute to the ESG management of our clients.

TSC Manufacturing and Supply Company ### Company Overview Company Name: Tokyo Steel Co., Ltd. Head Office: Kasumigaseki Tokyu Building 15F, 3-7-1 Kasumigaseki, Chiyoda-ku, Tokyo Established: November 23, 1934 Business Activities: Manufacturing and sales of steel ingots, various steel products, special steel, and iron and steel products. Securities Code: 5423 Homepage: https://www.tokyosteel.co.jp/

Project Overview - 1 Project Name: New Head Office Construction for Joyo Bank (Parking Building) Client: Joyo Bank, Ltd. CMR: Nikken Sekkei Construction Management Co., Ltd. Designer: Nikken Sekkei Ltd. Supervisor: Nikken Sekkei Ltd. Scale: 3 stories, 4 tiers / Total floor area 3,526.76㎡ (Volume target area 2,796.61㎡) / Capacity 161 vehicles Constructor: Watahan Solutions Co., Ltd. (Main building construction by Shimizu-Kabuki Specified Construction Joint Venture) Construction Period: January 5, 2026 - April 30, 2028 Estimated TSC Usage: 67 tons for columns CO2 Emission Reduction (compared to blast furnace steel): Approx. 69% reduction

This project is planned under the concept "Cross Point," aiming to be "a regional symbol where various stakeholders such as customers, local residents, and employees connect, continue to create value together, and contribute to the creation of a sustainable regional society." Through the certified car park using TSC materials adopted this time, we will contribute to the creation of a sustainable regional society.

Completed Image (Provided by Nikken Sekkei Ltd.)

### Company Overview Company Name: Joyo Bank, Ltd. Head Office: 2-5-5 Minamicho, Mito City, Ibaraki Established: July 30, 1935 Business Activities: General banking services including deposits, loans, and foreign exchange. Securities Code: 7167 (Mebuki Financial Group, Inc.) Homepage: https://www.joyobank.co.jp/

Project Overview - 2 Project Name: (Provisional Name) San-A New Head Office and Food Processing Center Construction (Parking Building) Client: San-A Co., Ltd. Designer: Watahan Solutions Co., Ltd. First-Class Architect Office Supervisor: Watahan Solutions Co., Ltd. First-Class Architect Office Scale: 6 stories, 7 tiers / Total floor area 13,091.39㎡ / Capacity 704 vehicles Constructor: Watahan Solutions Co., Ltd. Construction Period: February 15, 2026 - March 15, 2027 Estimated TSC Usage: Partially 123.3 tons for columns CO2 Emission Reduction (compared to blast furnace steel): Approx. 69% reduction

San-A Co., Ltd. aims to improve long-term corporate value by rebuilding its new head office and food processing center, and this car park also contributes to ESG management.

Completed Image

### Company Overview Company Name: San-A Co., Ltd. Head Office: 7-2-10 Oyama, Ginowan City, Okinawa Established: May 28, 1970 (Founded: January 5, 1950) Business Activities: Retail of food products, clothing, home appliances, daily necessities, and other residential related products. Securities Code: 2659 Homepage: https://www.san-a.co.jp/