Sekisui House, Ltd.

Working closely with suppliers for sustainability

Sekisui House is an industrialized housing manufacturer boasting a cumulative total of 2,259,715 housing starts (figure as of July 31, 2015) since the company was founded in 1960, making it the largest supplier of houses in Japan.

The following two cases are examples of initiatives taken by Sekisui House to conserve biodiversity in the course of its business activities.


Case 1: Gohon no ki landscaping project to support ecosystems

Even small spaces such as residential gardens and urban parks can be a part of the ecosystem network with trees and plants that are friendly to living things.

Sekisui House is also one of Japan’s largest landscapers with its landscaping business alone recording annual sales of some 50 to 60 billion yen. This is because the construction of houses is accompanied by the planting of trees to create residential gardens and to develop the urban landscape. Following the end of the world war, landscaping in Japan was strongly inclined to use garden species selectively bred for their appearance and exotic species. But with the increasing destruction of nature due to urbanization, Sekisui House came to the decision that it was necessary to conserve ecosystems in residences as well, and from 2001, began proposing to customers that they plant local indigenous species that will contribute to the conservation of biodiversity. This landscaping concept is called Gohon no ki, literally “five trees,” so named with the hopes of planting three trees for birds and two trees for butterflies. It does not mean the planting of just five trees.

When the project was started, there were few indigenous species available on the market. Sekisui House thus had its in-house tree doctor select species while consulting closely with experts from environmental NPOs and other knowledgeable organizations, and sought the cooperation of a network of some 50 tree growers and landscapers to grow these species. Consumers were informed of the benefits and encouraged to take action. As a result, in fiscal 2013, Sekisui House alone planted over 1 million trees including indigenous species, and a cumulative total of more than 10 million trees have been planted since the start of this project.


Case 2: Wood procurement guidelines for wood used in housing construction

In the procurement of wood, focus is placed on cooperation to promote improvements by sharing recognition of social challenges and moving forward to solve them.

Housing construction requires vast amounts of wood─about 5 metric tons for a 150 ㎡ lightweight steel frame house and about 15 tons for a wooden house constructed of laminated lumber (Sekisui House figures). The amount of wood used annually by Sekisui House surpasses 300,000 ㎥. The company recognizes that the procurement strategy for wood, which is a valuable biological resource, is an important concern for business continuity given the complexity of its traceability and distribution channels. With the aim to use FairWood─sustainable wood that considers biodiversity─Sekisui House formulated its own 10-principle Wood Procurement Guidelines with the cooperation of FoE Japan, an international NGO dealing with environmental problems, and has been applying these guidelines since 2006.

Because housing construction is a broad-based industry, in order to implement the guidelines, about 60 wood building material suppliers were requested to submit traceability information regarding their wood material, and by scoring and ranking the wood, the suppliers were encouraged to make improvements. The evaluation, however, does not regard certified products as absolute. With the view to supporting the operations of small producers who face difficulty in acquiring certification, it also takes into consideration features such as agroforestry and community forestry, and the social aspects of the producer. This activity has been highly lauded by parties outside the company, and among other recognitions, it was awarded the highest prize at the Japan Sustainable Management Awards.