Basic policy

Net Zero Energy Houses (ZEH) and other housing measures in Japan offer guidance to creating eco products as well as advocate excellent long-term housing as an asset. We conduct housings sales in a way that is able to contribute to a sustainable society while satisfying the needs of customers from reducing primary annual energy consumption by recommending houses with ZEH specifications and providing homes able to stand up to disasters in addition to providing products which maintain and sustain comfortable living.

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Promotion of net zero energy house (ZEH) specifications

The household sector in Japan still has high level emission of CO2 although the trend has slowed down. Japan has launched policy targets that aim for more than half of all custom-built detached houses constructed by housing manufacturers and other companies to be ZEH compliant by 2020 in the measure to counter global warming approved by Cabinet decision in May 2016. ZEH is a scheme for housing to provide less than zero annual net primary energy consumption by combining equipment to generate energy such as high thermal insulation efficiency, energy-saving equipment, and solar power generation.

Wood is conventionally a renewable natural resource that absorbs and stores CO2 during its growth process. As well as using wood for its principal structural members, Sumitomo Forestry has offered housing proposals where residents can live comfortably all year round by incorporating its own unique Ryouonbou design, which takes advantage of natural blessings such as the wind and sun. The Company’s expertise in utilizing these unique characteristics of wood and blessings of nature together with its technologies for the reduction of energy consumption, such as improvements in thermal insulation as well as the adoption of energy-saving equipment, and its technologies for the smart use of energy, such as equipment for generating and storing energy and HEMS*1.

Toward the ZEH targets established by Japan, Sumitomo Forestry has set the goal to standard ZEH at 80%*2 by fiscal 2020, and it has reached 33%*2 as of fiscal 2017. We are making greater insulation efficiency in buildings and around openings as well as built-in solar power generation systems basic specifications as of April 2017 in our new housing.


ZEH Standardization Target (2020)

ZEH Standardization Performance (2017)

*1 Home Energy Management System— a system whereby residents can visualize the amounts of energy they generate and use

*2 Values include Nearly ZEH while they exclude Hokkaido and Okinawa Pref. for their cold and hot weather respectively. The fiscal 2017 results and 2020 targets for Hokkaido are respectively 1% and 51%. While ZEH is defined as a primary energy reduction rate of 100% including solar power, Nearly ZEH is defined as between 75% to 100%.


Wooden Houses with Superior Insulation

If the thermal conductivity of wood is 1, the thermal conductivity of concrete would be almost 13 and steal upwards of 440. Wood as a material is a superior insulator to mitigate the transfer of heat. In addition, Sumitomo Forestry uses high-performance thermal insulators based on its own unique standards.

Superb Insulation of Wood

Superb Insulation of Wood

Unique Standards of Thermal Insulators of Sumitomo Forestry

Unique Standards of Thermal Insulators of Sumitomo Forestry

Limiting Energy Loss with Highly Insulating Glass

Windows cause the greatest loss of heat in living spaces. Shielding interior spaces from heat in the summer and preventing heat from escaping in the winter is vital. Sumitomo Forestry uses low-E multi-layered glass for windows causing a large amount of heat loss. Argon gas or krypton gas are injected between the multi-layers of glass to mitigate heat transfer to the air while the panes are coated with special metal film. The superior thermal insulation and insulation properties shield interior spaces from heat in the summer and prevent heat from escaping in the winter.

Low-E multiple layer glass

Low-E multiple layer glass


Heat Loss Ratio of Houses

Double Power Generation

Sumitomo Forestry recommends the installation of solar power generation panels as well as eco-farm residential fuel cell units. Double power generation can generate the necessary electricity for daily life in the home. Furthermore, Home Energy Management Systems (HEMS) realize zero energy homes (ZEH specifications) by proficiently managing energy consumption throughout the home.

Trends in installation rates of environmentally conscious equipment (new orders)

FY 2013 FY 2014 FY 2015 FY 2016 FY 2017
Solar power generation systems 51% 43% 35% 48% 46%
Ene-Farm units 53% 51% 43% 34% 34%
Eco One*1 - - - 16% 18%
Environmentally conscious equipment installation rate*2 72% 66% 58% 68% 69%

*1 Hybrid electric and gas hot water and central heating systems

*2 Installation rate of solar power generation system or Ene-Farms until fiscal 2015. Fiscal 2016 includes Eco One on the left

Sales of The Forest BF Detached Houses that Achieve Open Spaces and ZEH Start

Sumitomo Forestry further evolved its unique Big-Frame Construction Method (BF Method) with the release of The Forest BF throughout Japan (excluding Okinawa Pref.) in April 2017. The Forest BF provides comfortable habitability in even more open spaces than before through flexibility in the height of ceilings and beams with new patented technology. In addition to offering insulation efficiency greater than the local standards, The Forest BF can also achieve ZEH, which requires zero or less primary energy consumption each year, through equipment such as solar power generation systems. Moreover, we have adopted versatile partitions that do not require structural materials to build a structure with less waste when changing room plans such as the partitions separating living areas for children and parents alike. This product aims to receive orders of 5,500 houses a year.

Combining Comfortable Habitability and High Environmental Performance in The Forest BF

Combining Comfortable Habitability and High Environmental Performance in The Forest BF

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Proposals for Renovations to Enhance Performance

Sumitomo Forestry Home Tech Co., Ltd. promotes renovations from energy-saving points of view. This brings success in reducing the environmental impact by proposing solutions through thermo insulation as well as installation of facility equipment with high energy efficiency together with better thermal efficiency. The insulation renovation, specifically, can mitigate the health risk from heat shock in addition to lower the cost of heating and lighting.

We propose new lifestyles that reduce the energy consumed in daily life and decrease lifetime heating and lighting costs by heightening insulation efficiency and using energy-saving equipment.

We will continue to focus on seismic retrofitting proposals and actively strive to bring about excellent long-term housing in existing properties as well as long-term excellent extension and alteration standards by improving the performance in thermal efficiency, energy-savings and seismic retrofitting.

Installation of a Thermal Insulator

Restoration of World Heritage Historic Houses: Supervising Restoration of the World Heritage Ninna-ji Temple Shorinan Residence

Sumitomo Forestry Home Tech has handled a wide range of restoration of historic homes as a way to visit old to learn new impassioned about the quality of wood and traditional wooden construction. World Heritage Ninna-ji Temple Shorinan Residence restorations completed in September 2017 were executed with the aim of achieving a building with the old tastes of Japan. The restorations left original furnishings as much as possible, such as the rare structural beams, as well as bringing life back to the charm felt in the accommodations from that time.

We also made consideration to the construction method as Ninna-ji Temple Shorinan Residence is an area designated as a buried cultural property. When newly setting the foundation as part of the reinforcement work for seismic resistance, concrete was poured without any excavation of the subsoil.

In addition, Sumitomo Forestry Home Tech achieves renovations that leveraged its design and construction capabilities, such as the elimination of level differences in the floor of the building to provide a barrier-free interior.

In the future, we will not only renovated detached houses but also promote the expansion of our business to non-resident and commercial building sectors.

Restored Ninna-ji Temple Shorinan Residence

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Research and Development of Life Cycle Carbon Minus (LCCM) Housing

Sumitomo Forestry is engaged in the development of Life Cycle Carbon Minus housing to achieve negative CO2 emissions across the entire life cycle of a home—from material procurement, occupation and renovation through to demolition and disposal—by using environmental sound equipment such as solar power generation systems.

In addition to effective use of electricity in housing that uses technology such as energy storage systems, we conducted inspections through simulations in our research into efficient use of energy which began in fiscal 2016. Sumitomo Forestry also began looking into the effectiveness of Vehicle-to-Home (V2H) and Vehicle-to-Grid (V2G) when introducing electric vehicles expected to become a standard in the future. Moreover, as a way to better examine things from the resident perspective, we have organized the specifications for the outer skin of housing by defining target values for the insulation efficiency necessary from the perspective of comfort and health. In the future, we plan to further research and development not only in simple energy savings but also the impact the living environment has on the sensibilities of people.

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Carbon Stock in the Housing & Construction Business

Trees retain CO2 as carbon even after they are turned into products. Constructing wooden houses can therefore be likened to building forests in the city. The total domestic carbon stocks in timber that was used in construction of the houses in the MOCCA (timber solutions) business in fiscal 2017 reached 185,000 t-CO2. The Sumitomo Forestry Group contributes to measure to counter global warming by increasing carbon stocks for forests and cities.

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Sales of Home Adapted to Climate Change

Disaster Recovery Guidelines were put in place in the Housing and Construction Division and measures and action guidelines for operations were defined to quickly and accurately respond to damages from natural disasters to our customers’ houses as they become more prevalent due to climate change.

On November 4, 2016, BF-Si Resilience Plus was released to pursue security, safety and comfort when disasters such as earthquakes or flooding strike. The BF Method that boasts structural strength only offered by Sumitomo Forestry ensures the safety of buildings and provides functionality for an uninterrupted lifestyle until recovery even when lifelines are cut thanks to equipment such as enhanced storage space, solar power generation systems, wall-mounted electrical boards and water tanks. A video intercom with a network camera allows the interior to be clearly seen with a wireless camera as well as gives owners the ability to check the state of their house in a disaster even while out-and-about. The large storage space helps keep rooms clean in daily life while the original built-in furniture effectively prevents the furniture from toppling in an earthquake and can achieve a space in harmony with the interior.

Sales of Home in-line with Various Needs and Lifestyles

The Housing and Construction Division proposes housing to a broad range of customers from first time home buyers to married couples that plan to live with their children in multi-generational homes or who plan to live as a couple after their children are grown.

DUE CLASSO was released as custom-built housing for double-income families in August 2017. In response to needs such as efficient traffic lines and room plans easy for families to interact as well as storage ideas and the latest equipment, DUE CLASSO proposes Saku-kaji (prompt housework), Tomo-kaji (housework together) and Shin-kaji (new housework). These innovations are plentiful and help families spend a wonderful time together in this important space created through family cooperation. DUE CLASSO helps create a living space to achieve a leisurely lifestyle in both personal and professional life.

In addition, Forest Selection BF was launched to propose 1,000 carefully selected plans from approximately 30,000 proven custom-built homes in November 2017. This housing is realizing living suited to the needs and lifestyles of customers from a rich selection of choices.

Both of these products promote ZEH specifications to provide living spaces that value the lifestyle environment as well as the global environment.

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Initiatives for Overseas Housing

Sumitomo Forestry is furthering the expansion of the housing business overseas centered upon detached house sales in America and Australia. We sell environmentally-friendly housing in addition to fully grasping the culture of each area and the way people live to provide housing tailored to the demand.

Sales of Environmentally-friendly Housing Overseas

The Sumitomo Forestry Group sells housing with high energy-saving performance overseas.

In 2001, Henley Properties, a Group company, drove forward efforts to enhance energy-saving performance in the Australian housing industry, such as pioneering its own standard specifications ahead of competitors, by recommending a five-star energy rating*1 for the standard energy-saving performance in Victoria at the time. Efforts toward the environment accelerated further after the involvement of the Sumitomo Forestry Group in 2009. We conducted a variety of initiatives to reduce the environmental impact, including the realization of a commercial zero emission house*2 for the general consumer for the first time as a major builder in the country.

In Victoria, we use a blended cement replacing approximately 20% of cement, the primary ingredient in concrete used in foundations of homes, with fly ash (ash produced when burning charcoal) and blast furnace slag (byproduct separated from iron ore in the iron manufacturing process in blast furnaces). The blended cement reduces CO2 emissions by about three tons per home in the construction stage.

Japanese housing generally uses multi-layered glass, but this is not common practice in Australia due to the cost. More than 80% of the new housing still uses single-pane glass. However, in 2018, we were the first in Victoria to make multi-layered glass a standard specification to increase the insulation efficiency of homes*3.

We are also actively working to improve airtightness. The homes built by our Group company have shown airtightness three times higher than the average home in Australia shown by airtightness inspections conducted in 2017*4.

Henley Properties is taking advantage of the know-how cultivated in efforts to develop energy-saving housing over many years in a wide range of endeavors. As interest in realizing a sustainable society grows worldwide, Henley Properties is striving to develop housing with a high-level of energy performance by continually conducting improvements of materials and equipment as well as surveys of performance.

*1 An evaluation metric of the energy burden for heating and cooling the inside of a building in Australia. Insulation, windows, the type, size and orientation of the building, and the climatic zone are all items included in this metric. The highest rating of 10 stars indicates that no heating or cooling whatsoever is needed to maintain a comfortable indoor living environment. Five stars indicate that the building has high insulation performance, but that a minimum of energy is required for heating and cooling. The five star standard specifications pioneered by Henley Properties brought competitors to do the same. As a result the government of Victoria enacted policy to make five stars the standard. Thereafter, Henley Properties became a leader in environmental performance standards in the Australian housing industry through efforts that including raising the internal standard to six stars which then led Victoria to also raise theirs standards to six stars.

*2 Environmentally-friendly housing expected to have an energy-saving effect of more than 70% compared to conventional housing.

*3 Multi-layered glass effective in improving insulation efficiency of homes by limiting the thermal reflux to 35% compared to single pane glass.

*4 The average value for Henley Properties is 5 ACH where the average housing in Australia is 15.4 ACH (ACH is an index that indicates the air leakage per hour at a 50 PA indoor-outdoor air pressure difference. The lower the value the higher the airtightness).

Henley Properties Home

Henley Properties Home

Inspection of Airtightness Performance

Inspection of Airtightness Performance


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