This study aims to evaluate the effectiveness of the district unit plan as management tools and suggest the improvement scheme by identifying the problems and causes in the establishment and application of district unit plan to the existing residentia...
This study aims to evaluate the effectiveness of the district unit plan as management tools and suggest the improvement scheme by identifying the problems and causes in the establishment and application of district unit plan to the existing residential area.
Relationship between the street and buildings, important factor of regional characteristics, plays a large role for the quality of residential environment as well as urban landscape. Relationship between buildings and building and outdoor space is decided by urban planning, and controlling of road and the outline of building in urban planning is the scope of urban management planning.
District unit plan of urban management planning is different from general urban planning in that it can control the urban architectural regulation in m-ore detailed manner than use district according to the regional condition and characteristics, and it is efficient urban management tool for specialized env-ironment by supplementing urban management through use zoning and dist-rict. Even though a guideline of district unit plan is released by Seoul metropolitan government in order to apply district unit plan for solving diverse a-nd complicated urban problems, it is difficult to apply in consistent with the main goal due to its complicated contents and regulatory characteristics.
In this paper, detailed analysis is carried out on ‘the 1st district unit plan around Seoul National University’ where district unit plan was established on the 2nd residential area in urbanized area and problems and improvement scheme is suggested based on the guideline of district unit plan and current regulations.
In chapter 2, domestic and overseas urban planning systems and urban management planning schemes cases are compared.
1) New York City’s Zoning system is enforceable and it regulates concretely and in detail most restrictions by use zoning designation of Seoul metropoli-tan government and items controlled by district unit plan.
2) Japan’s use zoning categorization and regulations are similar to Korea’s but they apply different standards of restrictions to the same residential area.
3) Japan’s district planning can apply or even exclude reinforced or relaxed restrictions imposed by building codes and upper use zoning, and it also pr-ovides the scheme to reasonably distribute the floor area to each zone.
In chapter 3, current situations of management and problems are reviewed about residential area in urbanized area by use zoning designation and district unit plan in urban management planning of Seoul metropolitan government.
1) Even though designated area as the 2nd residential area in Seoul is quite wide and heterogeneous, it is controlled under the uniform restrictions. This causes serious disorder in housing types and land use.
2) Due to the different effect of restriction by setback regulation of building code depending on the condition of facing street, site area, and site shape, it is difficult to predict and manage the results of restriction implementation.
3) Even though Seoul metropolitan government suggests the guidelines classified as general and special district unit plan, most items controlled in the guidelines for special district unit plan are identical to that for general district unit plan and the means of regulation for both are also nearly same.
4) Recently more district unit plan is being established on the residential area in the urbanized area, compared to the past cases which were carried out on the commercial area and semi-residential area or residential area for existing and planned apartment houses complex.
5) The same regulatory range of use zoning is repeatedly applied for the same range of use zoning in terms of items, levels, and implementation method of restrictions of district unit plan for environmental arrangement. Height limit also have little effect and there is no clear standard for the application of the height limit on the area facing streets and setback regulation.
In chapter 4, analysis is carried out on the application result of district unit plan established on the existing residential area of district unit plan area around SNU.
1) Adjustment of use zoning and establishment and application of infrastructure planning
- In case of district unit plan around SNU, distinction of use zoning became complicated due to upward change of use from residential area to semi-residential area.
- High density development and commercialization of semi-residential area causes problems such as infrastructure shortage in the surrounding residential area.
2) Establishment and application of lot design
- Conjunction developments cause large scale sites inappropriate to residential area and most of them are located in the high and steep area.
- There is no splitting plan and limit to the maximum area of the site, while there is merging plan and limit to the minimum.
3) Establishment and application of use planning
- Depending on the intended use of the building, they are distributed in the different ways, and the status of local physical characteristics and regulations are not irrelevant to the decision of the intended use of the building.
4) Establishment and application of floor space index and incentive plan
- Standard floor space index of district unit plan hardly work to limit the building scale except attracting to obey the public plan, because allowable floor space index is same to the upper limit of use zoning of Seoul.
-Big difference between maximum limit of floor space index and buildable floor space index means that building size is difficult to be secured and incentive can’t guarantee the increase of scale. Thus, recommended public plan is not likely to be accepted.
- Regulation on the building size by floor space index limit have little effect on the small residential plot, and the development size seems more controlled by building coverage ratio and building height limit than floor space index.
5) Establishment and application of height regulation
-By the designation of use zoning, same height limit is applied to the different areas which have different site conditions such as shape, level, and slope.
-Height limit by maximum number of stories in the 2nd residential area seems to have no effect.
-Some characteristics such the site or block with irregular shape or with most internal roads as a dead end play a role in limiting the number of stories.
-The current legal regulations and district unit plan is expected to lead to increase in the number of stories of buildings.
6) Establishment and application of building arrangement and shape
-The plan for the exterior of building is insufficient, because the district unit plan has focused on urban management factor such as development density so far.
-Uniform building line is likely to regulate excessively the building activity in each plot and it is impracticable due to the lack of implementation tool.
7) Designation of Special Planning Area
Part of the 3rd residential area near trunk road is designated as Special Planning Area and plan for the building line and open space is being established.
8) Establishment and application of public sector planning
-Private development seems unlikely to obey the public planning due to the impossible application of relaxed maximum size to the small site with irregular shape.
-Even if public planning is fully accepted, management of streetscape is likely to be difficult due to the irregular width of the street and the different size of surrounding buildings.
In chapter 5, the effectiveness of regulations of district unit plan is evaluated through the analysis in the previous chapters, and improvement scheme is suggested.
1) Unintended effect and problems of regulation happen in the process of building on individual plot, because district unit plan cannot play the institutional role appropriate to the main goal due to the lack of management system by designation of use zoning on residential area, establishment of district unit plan, and general regulations.
2) It is the items related to the building density that are the most tightly regulated by the use zoning and district unit plan. Even though district unit plan can apply different regulations according to the local condition and also can regulate architectural and planning factors, it cannot produce actual result due to the lack of regulatory tool and standard.
3) Even though it is difficult to find the causes and solutions for the establishment and management of district unit plan due to the complicated relations of many factors, improvement schemes can be suggested as follows; relationship between discretion right to upper regulation and related development project, management tools for the regulations linked to the detailed public plan about architectural activity in the area of established district unit plan, and decision of regulatory level and application criteria of district unit plan.
Discussion about improvement scheme without the real object tends to be abstract and general, because of the institutional characteristics of district unit plan which cannot be separated from the local specific situation. Thus, concrete improvement schemes are proposed for the regulations of district unit plan around SNU in accordance with the main improvement direction based on the previous analysis and evaluation of effectiveness.
1) Subdivision of use zoning classification considering characteristics of local usage
2) Limit on plot planning and maximum development site area
3) Limit on zoning and building use
4) Secured effectiveness of floor space index regulation and incentive
5) Diverse schemes for the application of maximum height and setback regulation
6) Architectural design linked with building codes
7) Public road planning considering the site conditions
In order to find improvement schemes for the residential area in the urbanized area, applied result of district unit plan is analyzed using guidelines of district unit plan, statistic data of building status, and simulation for predicting building activity. And improvement schemes are suggested following the visualization of system management tool and the problems of regulations through the evaluation. This study aims to increase the efficiency of land use by growing the management effectiveness of district unit plan on existing residential area in terms of institution, and contribute to the qualitative improvement of existing residential environment by improving excessive public restrictions on private properties and unintended regulatory effect on building activity.