Sumitomo Forestry believes that popularizing excellent long-term houses that become social assets is vital for creating a prosperous society. As such, the Company is promoting the following policies to extend the life of houses:
Concerning housing for which measures have been enacted to achieve their excellent long-term use, construction and maintenance/preservation plans are assessed by the competent authorities on a house-by-house basis to ensure compliance with certification standards. The achievement of certification brings preferential terms, including in areas such as taxation and interest rates on loans. In fiscal 2011, 85.1% of all houses constructed were granted excellent long-term housing certification.
We will step up initiatives to improve the rate of certification based on the Excellent Long-term Housing Promotion Act.
Sumitomo Forestry actively promotes the Japanese Housing Performance Indication System1 because it ensures safe and reliable houses, and also raises their asset value.
Design Performance Evaluation: 98.2% implementation2
Construction Performance Evaluation, which is recommended to customers to acquire along with Design Performance Evaluation: 87.6% implementation2
Sumitomo Forestry has set a minimum expected service life of 75 years1 for principal structural members to ensure that the houses it builds are highly durable and can be passed down over three generations. Standard specifications for the structural framework are set at Level 3—the highest level—for evaluations based on the Japanese Housing Performance Indication System with respect to Alleviated Deterioration.
Sumitomo Forestry has collaborated with Nisshin Steel Co., Ltd. and Nisshin Kokan Co., Ltd. to develop the Differential Settlement Correction Method for Housing. In regions with soft ground, this method lifts up each of the home's foundation blocks to correct the problem of differential settlement when it occurs. The three companies began jointly developing this method in 2006, and it has a number of advantages over other methods. For example, it is kinder to the environment than the conventional method that involves injecting chemicals into the foundation, while it also offers superior corrosion resistance and lower costs than the method that uses hydraulic jacks to lift the house. A patent application is pending.
Sumitomo Forestry provides skeleton infill homes—a design concept that separates the structure from the interior and equipment—based on the Company’s original Big-Frame construction method utilizing the wooden beam Rahmen structure. The structure’s strength and high versatility makes it possible to alter the layout according to changes that occur in future life stages.
In fiscal 2011, the Company took orders for 2,517 homes—around a 160% year-on-year increase—as the features of its products were appreciated by its customers.
Sumitomo Forestry offers three housing construction methods—Multi-Balance Construction Method, Big-Frame Construction Method, and Two-by-Four Construction Method—which excel in seismic, wind and fire resistance and meet various requirements. All structures that employ these three construction methods are among the recomended supecifications of Government Regulated Semi-Fireproof Construction Houses by the Japan Housing Finance Agency.
In April 2011, Sumitomo Forestry developed a technology that allows a traditional Shinkabe1 interior to be constructed in wooden buildings, such as a three-story wooden house, in semi-fireproof districts, without altering the standard depth of the pillars or walls in Sumitomo Forestry Home houses. A patent application is pending for this unique technology.
In its scrupulous attention to the details of its custom-built houses, Sumitomo Forestry proposes crime prevention measures from the site survey and design stage.
Sumitomo Forestry offers houses that integrate universal design as the foundation, which are comfortable for all members of the family and will be easy to live in for many years to come.
The Tsukuba Research Institute is conducting research based on human lifestyle engineering using 3D motion and view-tracking analysis equipment. In-home improvements are being made based on the results of this research, including spatial configuration and traffic-flow planning tailored to the family's lifestyle, dimensional planning designed to enable smooth and strain-free positioning and movements, as well as handrails and other materials to prevent accidents.
The Company raises awareness of the universal design concept among employees by having them experience living in the Universal Design House developed by the Tsukuba Research Institute and encouraging them to apply what they learn from this experience in their daily work. This includes simulating the experiences of an elderly person.
In December 2011, Sumitomo Forestry Crest Co., Ltd. published a building materials catalogue for housing for senior citizens. It features beautiful wood-grained furniture and fittings and large doorways with plenty of space for a wheelchair to pass, providing residents with homes that give them feelings of safety and comfort and also enable nurses to carry out their duties more easily. Not only the furniture and the fittings, but also the floors and the walls are made of wood and designed always with the resident in mind, providing a range of functions and a sense of refinement.
In October 2011, we launched the ikiki two-family home for young working couples and their still active parents. The homes are designed to facilitate intergenerational communication while also ensuring the residents have private time, with spaces both for independent and communal living. Moreover, these homes meet the Sound Insulation 60 Specification, as we used a newly developed method of constructing floors with highly efficient sound insulation, helping to provide a comfortable, stress-free living environment.
In June 2011, we launched the lifestyle proposal-type mamato home, based on the concept of “creating homes where both mothers and their families can be happy.” The homes were developed mainly via consulting with our female employees who were raising children or had done so in the past, and their ideas and concerns were reflected in the home’s specifications. For example, we use traffic-flow planning to improve housework efficiency and also fully utilize the results of the research that won us a Kid’s Design Award.
Sumitomo Forestry adheres to its Timber Procurement Philosophy and Policy with the conviction that it should procure the timber it uses to build houses from forests that are managed according to sustainable methods.
Sumitomo Forestry classifies and manages timber as certified and non-certified in all stages from distribution and processing through house construction, in recognition of which it has obtained Chain of Custody (CoC)2 certification of SGEC1.
This enables the Company to display the SGEC logo on its applicable products and promote environmentally sound materials. All of the Company’s engineered standard studs used in Sumitomo Forestry houses in Hokkaido are labeled to indicate that they are made of Japanese larch grown in Hokkaido.
Sumitomo Forestry promotes the use of Japanese timber in housing, and in fiscal 2008 increased the proportion of Japanese timber to 70% of the principal structural members. Since that time, this target has been continuously achieved and is helping to revitalize Japan’s forests (applicable structures are those in which the main Multi-Balance Construction Method is employed). Sumitomo Forestry also builds houses that use Japanese timber for 100% of the principal structural members, limited to certain product models and regions.
The Company confirms the legality of all the timber it uses for home construction, whether Japanese timber or imported timber.
Initiatives are being implemented under the Action Plan stipulated by the Timber Procurement Philosophy and Policy.
In its rental properties business, Sumitomo Forestry supplies wooden rental housing under the Forest Maison brand name, built with the Company’s original Two-by-Four and Big-Frame Construction Methods. By building structures with excellent seismic resistance and durability while also taking into consideration the surrounding environment and addressing various other requirements, Sumitomo Forestry provides homes in which people can live for a long time with peace of mind.
In July 2011, the Company launched Forest Plus rental homes that are designed to be considerate to their surrounding environment. It can flexibly provide Forest Plus proposals tailored to the site conditions, such as the land formation and local road network, while also addressing the legislative environment including regulations on the plot ratio and the degree of slant. A feature of these homes is that they address a wide range of customer needs, from the freedom to decide the home layout to the option to add to the equipment specifications, through to the ability to create life plans, such as for asset utilization and tax strategies.
Sumitomo Forestry has established a Long-Term Support System in order to help its customers live comfortably in their houses for as long as possible. This system provides maintenance support for 60 years after a house is handed over to its owner.
The Long-Term Support System offers a standard 10-year warranty, which can be extended up to 20 or 30 years on the structural frame and waterproofing, as long as fee-based maintenance work judged necessary by the Company, such as anti-pest treatment in the 10th year, is performed.
In February 2011, Sumitomo Forestry launched repair savings and renovation loan schemes to support the maintenance work required to maintain the functionality of Sumitomo Forestry Home houses. The objective is to maintain the functionality of Sumitomo Forestry Home houses to ensure that they remain safe, secure and comfortable, by encouraging regular maintenance work.
About 40% of existing detached wooden houses are considered to be insufficiently earthquake resistant, and therefore require seismic upgrading to ensure security for their occupants. Sumitomo Forestry Home Tech Co., Ltd. is developing earthquake-resistant renovation technologies that alleviate the burden for customers while making the most of existing houses.
The Company has developed a new construction method that can easily convert a traditional Japanese shinkabe wall into a shear wall. The method entails positioning a rigid-joint beam shear between the pillars without having to remove the nageshi beams or ceiling.
The beam incorporates the Company’s original T-shaped rigid metal fittings to strengthen the supporting walls. In comparison to the conventional construction method, which requires removing the nageshi beams and ceiling to construct the shear wall, this method reduces the extent of the construction required and its costs.
The Company has applied for a technological evaluation by the Japan Building Disaster Prevention Association (DPA -47) and is awaiting patent approval
Sumitomo Forestry Home Tech Co., Ltd. has developed a number of technologies that propose renovation by utilizing technology and design capabilities to enhance the structural safety of wooden houses, and five patents have now been obtained together with Sumitomo Forestry’s Tsukuba Research Institute.
In April 2011, the TV program Hyakunen Meika (100-Year-Old-Historical-Homes), introduced some case studies of Sumitomo Forestry Home Tech’s renovations of traditional homes. Then in September 2011, Renovations Bringing Wisdom from the Past to Tomorrow: Rehabilitation of Traditional Japanese Houses to Meet the Needs of the People who Live in Them was released to bookstores nationwide, which is the third in its series of books introducing examples of the Group’s renovation of traditional homes. These examples highlight how the Group is renovating traditional homes to improve their anti seitmic and energy conservation while leaving untouched their unique historical features, thereby communicating to the world the appeal of Japan’s existing stock of traditional homes.
Sumitomo Forestry’s Tsukuba Research Institute and Sumitomo Forestry Home Tech Co., Ltd. will continue to research and validate renovation technologies in order to realize comfortable homes, including the seismic retrofitting of traditional structures, establishment of simple seismic reinforcement, weathering of traditional homes, energy-saving renovation, and sound renovation.