Net-ZEB and ZEH-M Oriented Certification Acquired for a Mixed-use Facility Consisting of Office Space and Rental Housing for the First Time in Japan

On October 28, 2022, HAZAMA ANDO CORPORATION received the highest rank for overall building evaluation under the Building-Housing Energy-efficiency Labeling System (BELS)^（Note1）, as well as Net-ZEB certification (at least 100% energy reduction compared to conventional buildings), for the office portion of the Hazama Ando Tohoku Branch Building (provisional name) currently under construction in Sendai in northern Japan. On the same date, it also received the highest rank for overall building evaluation under BELS, as well as ZEH-M Oriented certification (at least 20% energy reduction), for the rental housing portion.

As a mixed-used facility consisting of offices and rental housing, this is the first time a building in Japan simultaneously acquired Net-ZEB certification and ZEH-M Oriented certification.^（Note2）

Moreover, this project is the first step in the Company's efforts to promote the facility management (FM) business for advancing effective use of real estate, such as domestic branch buildings. Construction began on the new building in July 2022, and with underground framework construction currently underway, the Company aims to begin operations around the end of fiscal 2023.

Net-ZEB Certification Label

ZEH-M Oriented Certification Label

Initiatives for Acquiring Net-ZEB and ZEH-M Oriented Certification

HAZAMA ANDO is engaged in realizing a carbon-neutral society. As it sets out to rebuild the Tohoku Branch Building, the Company aims to create a next-generation, energy-saving office building that enables good health and high productivity utilizing local characteristics. In terms of Net-ZEB, the building will realize a total energy reduction of 101% by decreasing primary energy consumption 56% through the adoption of various environmental technologies, including a ceiling mounted radiant cooling system using well water,^（Note3） and by creating 45% of the energy consumed by the building through solar power generation.

（１） Energy-saving and Energy-creating Technologies

① Ceiling-mounted radiant cooling system using well water (energy-saving technology)

The air conditioning system for the office floors will utilize a ceiling-mounted radiant cooling system in aims of saving energy, as well as of creating an office environment that is healthy and comfortable. This system will also allow for on-site groundwater (well water) sampling, and satisfies all well water usage criteria, thereby enabling the use of well water as an air conditioning heat source to further improve energy-saving effectiveness.

②Passive energy-saving technology

The Company will enhance the insulation performance of the entire building by selecting external wall materials with high insulation performance, reinforcing external rooftop insulation, adopting Low-E double-glazed glass^（Note4）, and reinforcing insulation between dwelling units, and will control solar radiation using eaves and balconies to reduce air conditioning loads.
The office floors are also designed with a natural ventilation system centered on internal stairwells as a means of reducing air conditioning energy during the spring and fall when air conditioning loads are low.

③High-efficiency facilities and equipment (energy-saving technology)

All of the lighting will use LED lights. In particular, office lighting fixtures will be designed to allow for individual control, which will enable offices to employ daylight sensors as a means of significantly reducing lighting energy. In addition, water heaters and air conditioning units on the apartment floors will use high-efficiency facilities and equipment to achieve energy-saving rates on the level of ZEH-M Oriented certification.

④Solar power generation using building walls (energy-creating technologies)

Installing solar panels over most of the rooftop area and the south-facing wall will ensure the building meets the energy-creating rates required to achieve Net-ZEB. The wall-mounted solar panels installed on the building’s south-facing side will also act as eaves that control solar radiation. Together with private power generators and storage batteries, these solar panels will also function as an emergency power source, and will contribute to ensuring BCP performance as the Company’s local flagship office.

(2) Environmentally-friendly Building Materials

The mat slabs and CFT columns will be made from a low-carbon, environmentally-friendly concrete that reduces CO2 emissions originating from concrete materials.
Depending on the area of use, structures will be made from concrete produced using CfFA (high-quality fly ash) and concrete produced using type B blast furnace cement and fly ash (BBFA). Both types of concrete reduce CO2 emissions by replacing some of the raw materials with industrial by-products, including incinerated ash and slag.

   
Through this project, HAZAMA ANDO will create a next-generation, energy-saving, and environmentally-friendly building. Along with applying and verifying its know-how regarding the benefits of ZEB conversion, including comfort and BCP performance, as seen from multiple angles in one of its own properties, the Company will also connect this effort to future proposals to customers.