Building code regulations are an important factor in real estate development and construction planning. However, by utilizing the appropriate systems, these regulations can be reasonably relaxed to achieve more efficient and attractive development.
In this article, INA&Associates, Inc. provides a detailed explanation of the Single Lot Certification and the Comprehensive Design System for real estate investors and developers. By properly understanding and utilizing these systems, you can enjoy the benefits of relaxed floor-area ratios and streamlined building regulations, and realize more profitable real estate development.
These systems are especially important options for those involved in condominium and real estate development. We hope that you will use this knowledge to understand the complex regulations of the Building Standard Law and to make appropriate use of your land.
The "One Complex Certification " is a system based on Article 86, Paragraph 1 of the Building Standard Law, officially called the "Comprehensive Design System for One Complex. This system is a special exception system in which building regulations are applied to multiple buildings by deeming each site as a single site.
Normally, under the Building Standard Law, only one building can be constructed on one site, as the "one site, one building" principle is applied. However, by acquiring the " single site certification," multiple buildings can be treated as being on the same site, and regulations such as floor-area ratio and building-to-land ratio can be applied to them in an integrated manner.
The main purpose of this system is to promote rational development of land in a single lot. Especially in the development of large-scale residential complexes and commercial facilities, it allows for harmonious development as a whole without subdividing the land into smaller lots.
According to statistics from the Ministry of Land, Infrastructure, Transport and Tourism, as of the end of March 2015, there were 17,764 projects, the majority of which were for residential use (16,250). This indicates that this program is widely used in condominium and residential complex development.
The following conditions must be met in order to qualify as a single-family residential development.
Basic Requirements
Technical Requirements
By meeting these requirements, development plans that would be difficult to realize under conventional building regulations can be made possible.
The Comprehensive Design System is also the official name of the Single Lot Approval System, which is explained in detail here as a system based on Article 86, Paragraph 1 of the Building Standards Law. The core of this system is to enable more flexible and efficient building planning by treating multiple sites as one.
Under the conventional building regulations, the floor-area ratio and building-to-land ratio are applied separately to each site, which means that the full development potential of a site may not be utilized, depending on its shape and location. By utilizing the comprehensive design system, these restrictions can be solved in a rational manner.
One of the greatest benefits of this system is the floor-area ratio relaxation. Specifically, the following mitigation measures are applied.
Transfer of floor area
Floor-area ratio can be transferred between multiple buildings. For example, the excess floor area in Building A can be transferred to Building B to make Building B taller. This allows for more efficient land use as a whole.
Rationalization of Road Diagonal Restrictions
The road shading restrictions are applied based on the maximum width of the road that the subject area abuts. This makes it possible to construct taller buildings even in areas facing narrow roads.
Rationalization of shading restrictions
Sunshading restrictions are applied to multiple buildings as a single unit, so that even if individual buildings cannot meet the requirements, construction is possible as long as the entire building can clear the restrictions.
The application for the Comprehensive Design System follows the steps below.
| Steps | Contents | Approximate time frame | Main items to be confirmed |
|---|---|---|---|
| Preliminary consultation | Consultation on planning outline | 1-2 months | Confirmation of system applicability and basic requirements |
| Submission of basic plan | Consultation on detailed plan | 2-3 months | Technical requirements, coordination with related departments |
| Application for certification | Submission of formal application documents | 1-2 months | Final review and decision on certification |
| Building Inspection | Confirmation of compliance with Building Standard Law | 1 month | Application for confirmation based on the approved details |
Application requires specialized knowledge and experience, and collaboration with architects and urban planning specialists is essential.
In real estate development, the single lot certification (comprehensive design system) and the comprehensive design system tend to be confused because of their similar names, but they are completely different systems. It is important to clearly understand the difference between the two systems in order to select the appropriate system.
| Item | Single site certification (comprehensive design system) | Comprehensive Design System |
|---|---|---|
| Basis Laws and Regulations | Article 86, Paragraph 1 of the Building Standard Law | Article 59-2 of the Building Standard Law |
| Main purpose | Integrated application of regulations to multiple buildings | Relaxation of floor-area ratio by securing open space |
| Target buildings | Multiple buildings (mainly housing complexes) | Single buildings (high-rise buildings, condominiums) |
| Site requirements | Integration of multiple sites | Single site above a certain size |
| Details of mitigation | Floor-area transfer, relaxation of diagonal restrictions | Floor-area ratio increase, height restriction relaxation |
| Open space | Not required | Required (above a certain percentage) |
| Examples of application cases | Residential complexes, multi-unit condominiums | High-rise apartments, commercial buildings |
Selection based on the scale of development
For small to medium-sized developments with multiple buildings, the single complex certification is appropriate . On the other hand, the Comprehensive Design System is effective for large-scale single-building developments where the maximum floor-area ratio is desired.
Selection by Location
The Comprehensive Design System is suitable for a high-rise development on a limited site in the city center, while the Single-Plex Approval is suitable for a residential complex development on a large site in the suburbs.
Perspectives on Business Profitability
The Comprehensive Design System requires the securing of open space, which reduces the amount of land available for projects. However, the large increase in floor-area ratio may result in higher profitability. The single lot certification does not require open space, so the effective land utilization rate is higher.
Examples of One-Plex Certification in Use
Large-scale residential complexes developed by major developers are using single lot certification to achieve efficient layout planning. For example, by combining low-rise and high-rise buildings, the floor-area ratio is maximized while creating an attractive living environment as a whole.
Examples of Utilization of the Comprehensive Design System
In redevelopment projects in central Tokyo, we have utilized the comprehensive design system to secure open space on the ground level, while achieving a significant increase in the floor-area ratio in the upper floors. This contributes to the improvement of the local environment while at the same time ensuring the profitability of the project.
Economic Advantages
By utilizing the One Complex Certification, land does not need to be subdivided and registration and surveying costs can be significantly reduced. In addition, by shifting the volume of land, more efficient building plans can be made, which can be expected to improve business profitability.
Greater Design Flexibility
Because multiple buildings can be planned as a single unit, restrictions on building placement and height are eased. This allows for more attractive and functional development plans.
Improved efficiency of maintenance and management
The ability to manage multiple buildings as a single entity allows for more efficient placement of common facilities and reduced management costs. This effect is especially noticeable in large residential complexes.
Complexity of the procedure
The application for certification requires specialized knowledge and many documents, making the process time-consuming and costly. In addition, prior consultation with the specific administrative agency is mandatory, and changes to the plan may be required.
Future Restrictions
Once a plan has been approved, future changes may be difficult. When changing the use of the building or making additions or renovations, certification may be required again.
Strict technical requirements
Safety, fire prevention, and sanitary requirements are strictly reviewed, requiring detailed study from the planning stage. This may increase design costs.
| Item | Merit | Demerit |
|---|---|---|
| Floor-area ratio | Large increase in floor-area ratio possible (up to about twice as much) | Actual building area is reduced by securing open space |
| Height restrictions | Absolute height restrictions and oblique restrictions are relaxed. | Strict examination of impact on the surrounding environment |
| Business Potential | Higher profitability due to high floor-area ratio | Maintenance cost of open space |
| Contribution to society | Contribution to improvement of urban environment | Strict qualitative requirements for open space |
| Procedures | Proven track record and high predictability | High application fees (from several hundred thousand yen) |
Proper risk management is essential when utilizing these programs. Particular attention should be paid to the following points.
Risk of legal revision
Amendments to the Building Standard Law and related laws and regulations may affect the contents of existing certifications. Regular checks of laws and regulations and cooperation with specialists are important.
Market fluctuation risk
In long-term development projects, changes in market conditions may necessitate revisions to business plans. Flexibility must be maintained in the planning process.
Technical Risk
Complex building plans may encounter technical problems during the construction phase. It is important to conduct sufficient studies at the design stage and select an experienced construction contractor.
The application process for single-site certification involves several stages. Appropriate preparation and response at each stage will directly lead to success in obtaining certification.
Stage 1: Summary Consultation
First, an overview consultation is conducted at the Building Guidance Section of the specified administrative agency. At this stage, the basic applicability of the plan is confirmed and necessary considerations are clarified.
Phase 2: Preliminary Consultation
Detailed planning documents are prepared and preliminary consultation is conducted. At this stage, detailed confirmation of technical requirements and coordination with related departments will be conducted. Consultation with the Fire Department, Environment Bureau, Construction Bureau, etc. may be required.
Phase 3: Application for certification
The final application documents are submitted, reflecting the points raised in the preliminary consultation. The review period is usually 1-2 months, but may be extended depending on the complexity of the plan.
Phase 4: Application for Building Permit
After certification is obtained, an application for building permit is filed based on the Building Standard Law. Since the application for confirmation is based on the contents of the certification, the application proceeds more smoothly than a regular application for confirmation.
Basic Documents
| Name of document | Contents | Points to note |
|---|---|---|
| Application for Certification | Application form in the statutory form | Use the form designated by the specified administrative agency |
| Statement of Reason | Reason and effect of seeking certification | Specify the necessity and public interest of the project |
| Design document | Detailed design details of the building | (including structure, equipment, finishes, etc.) |
| Design drawings | Layout, floor plan, elevation, etc. | Note scale and description |
| Certificate of registered matters | Land and building rights | Must be within 3 months of issuance |
Technical documents
| Name of document | Contents | Specialty |
|---|---|---|
| Structural calculation sheet | Structural safety of buildings | Structural design first-class architect is required |
| Facilities Calculation Sheet | Water supply and drainage, electricity, air conditioning, etc. | Requires expertise in facilities design |
| Sunshade drawing | Shading impact on the surrounding area | Calculation by dedicated software |
| Traffic volume calculations | Impact on surrounding roads | Requires expertise in traffic engineering |
| Environmental Impact Statement | Environmental impact assessment | Requires knowledge of environmental assessment |
The following fees are involved in the application for single-site certification
Administrative fee
Professional fees
Other Expenses
Normally, a period of 6 months to 1 year is required from the application for certification of a single complex to the acquisition of certification. Proper management of this period is important in the overall project schedule management.
Key points for schedule management
The Single-Plex Certification and the Comprehensive Design System are extremely effective systems for real estate development. Appropriate use of these systems will enable development plans that are difficult to realize under conventional building regulations, and will significantly improve business profitability.
Criteria for System Selection
Requirements for Success
Direction of System Development
In recent years, these systems have become increasingly important from the perspective of urban planning. In particular, they are attracting attention as a means of maximizing the use of limited land resources, especially in urban areas.
Integration with Technological Innovation
The development of BIM (Building Information Modeling) and AI technologies has streamlined the study of complex building plans and the preparation of application documents. This is expected to lower the hurdles to utilizing the system and make it available for more projects.
Sustainability Considerations
With the demand for development that emphasizes reduction of environmental impact and harmony with local communities, the establishment of sustainable development methods that utilize these systems has become an important issue.
If you are considering using the One-Plex Certification or Comprehensive Design System, we recommend that you proceed with the following steps.
A1. The most significant difference is the composition of the subject building. The single complex certification (comprehensive design system) is a system in which multiple buildings are considered as a single site, and is mainly used for residential complexes and multi-unit condominium developments. On the other hand, the Comprehensive Design System is a system whereby a single building receives a reduced floor-area ratio by securing public open space, and is mainly utilized for high-rise condominiums and commercial buildings.
The decision to select this system should be made based on a comprehensive review of the scale and composition of the development plan, location conditions, and business profitability.
A2: It usually takes from 6 months to 1 year from the time of application to the time of certification. As for costs, the administrative fee is usually from 100,000 yen to 500,000 yen, and the total cost including professional fees is usually from several million yen to several tens of millions of yen.
However, since these fees vary greatly depending on the scale and complexity of the project, a detailed study based on a specific plan is necessary. We recommend early consultation with a specialist to estimate an appropriate time frame and cost.
A3: It is possible to make changes to the plan after certification is obtained, but depending on the details of the changes, it may be necessary to re-apply for certification. Minor changes may only require notification, but a new application for certification will be required for major changes in the layout or scale of the building, changes in use, etc.
It is important to formulate plans that take into account the possibility of future changes and to confirm in advance the procedures to be followed when such changes are made.
A4: Even small-scale developments may benefit sufficiently from the program, depending on the location and the nature of the development. In particular, the one-unit certification allows for the efficient layout of multiple buildings, which would be difficult to achieve with a stand-alone development.
However, considering the application costs and complexity of the procedures, it is more realistic to utilize the program for developments above a certain size. A detailed analysis of business profitability is required to make a concrete decision.
A5: When utilizing the Single-Plex Certification or Comprehensive Design System, it is especially important to carefully explain the project to neighboring residents and build consensus, since the development is often larger than a normal building project.
Specifically, it is necessary to hold briefing sessions at an early stage of planning, and to provide sufficient explanations and discussions regarding environmental impact considerations, noise and vibration countermeasures during construction, and post-completion maintenance and management methods. Building a good relationship with the neighborhood is directly linked to the smooth progress of the project and the maintenance of long-term asset value.