노후계획도시 특별법 시행에 따른 1기 신도시의 자본화 효과에 대한 다층적 분석 : 이중·삼중차분법에 의한 실증 연구

노후계획도시 특별법 시행에 따른 1기 신도시 아파트가격 변화를 분석했다.

This study began with a single question. When the Special Act on the Improvement of and Support for Aged Planned Cities took effect in September 2024, how did apartment prices in the five first-generation new towns of the Seoul Metropolitan Area—Bundang, Ilsan, Pyeongchon, Sanbon, and Jungdong—respond? More specifically, across the three-stage process spanning the policy announcement (February 7, 2023), the promulgation of the law (March 24, 2024), and its enforcement (September 15, 2024), at which stage did the market react most sensitively?

And how did the heterogeneity in redevelopment progress and in the floor-area-ratio (FAR) headroom across individual complexes differentiate that response? Above all, the weightiest question remains: can Korea truly avoid repeating the Japanese precedent, in which the relaxation of FAR regulations in central Tokyo accelerated the decline of the Tama, Senboku, and Chiba new towns?

To address these questions, the author constructed three models in a stepwise manner: Model 1, which examines the average effect across the first-generation new towns as a whole; Model 2, which probes how the institutional treatment is differentiated by redevelopment pathway; and Model 3, which traces how the capitalization effect diverges according to FAR headroom. Prior to the main estimation, the validity of the identification strategy was examined through a pre-trend test and an event study. The picture that emerged from the three models is anything but monotonic. Consider Model 1 first. The market scarcely moved when the policy was announced.

Yet once the law was promulgated, a price premium of approximately 2.55% emerged, hardening into 2.62% at the enforcement stage. What this reveals is that the Korean real estate market remains in a wait-and-see posture in response to abstract signals of governmental intent, and only begins to move prices at the very moment when the institutional change is legally confirmed. The landscape sketched by Model 2 is somewhat more nuanced. Compared with redevelopment projects in the pre-association-establishment phase, the Special Act generated a positive premium of approximately 4.10%.

Yet against redevelopment projects that had already crossed the threshold of association establishment, the negative gap of −3.27% could not, in the end, be reversed. This means that the institutional value delivered by the Special Act has a clear ceiling, and what draws that ceiling is, ultimately, the legal milestone of association establishment. Model 3 followed the canonical DDD specification by converting FAR headroom into a dummy variable based on the sample median (202%).

The DDD coefficient estimated at the enforcement stage was +0.0339 (p〈0.05), implying that complexes with greater FAR headroom captured an additional premium of approximately 3.4 percentage points relative to those with less. What Smith (1987) long ago termed "capitalization proportional to the rise in potential ground rent" was indeed operating, intact, in the Korean market. Even more striking is the pattern of temporal transition. The DDD coefficient, negative at the time of the policy announcement, flips to positive by the enforcement stage.

This dynamic corresponds almost precisely to the transition "from uncertainty discount to the capitalization of confirmed development gains" predicted by Capozza and Li's (1994) option value theory. The contributions of this study to the academic literature can be distilled into four points. First, this study is the first in Korea to construct a multi-layered analytical framework that simultaneously identifies, through three distinct comparative structures, how the three-stage legislative event differentially operates on the price structure of the market.

Second, by partitioning the control group according to whether the redevelopment association had been established and conducting a dual comparison, the study reveals that the institutional value of the Special Act exhibits an asymmetric structure in which the ceiling is set by the legal milestone of association establishment.

Third, by importing the canonical DDD specification refined in health economics into real estate policy analysis, the study opens a pathway for jointly testing, within a single model, Smith's (1987) rent gap theory and Capozza and Li's (1994) option value theory, and quantitatively substantiates the core propositions of these two classical theories with data from the Korean market.

Finally, by combining a spatial placebo test with a temporal placebo test in a dual placebo design, the study secured from multiple angles that the policy effects identified herein are causal effects uniquely attributable to the legal designation under the Special Act, rather than reflections of the general market dynamics of aged apartments or of pre-existing differential trends; this design offers a methodological standard for robustness checks that future studies on real estate policy effects can adopt. The trajectories of Tama, Senboku, and Chiba in Japan served as the mirror into which this study gazed.

The three risks—the straw effect produced by the absence of coherence between macro- and micro-level policies, the temporal mismatch between demand and supply, and demographic synchronization—are amply capable of being reproduced in Korea's first-generation new towns. To forestall such an outcome, the author proposes five policy directions: differentiated policy design tailored to each new town, complementary urban regeneration support directed toward adjacent non-beneficiary areas, the temporal coordination of phased redevelopment, the legal mandating of social mix, and the prioritized promotion of transit-oriented compact development. 이 연구는 한 가지 의문에서 출발했다.

2024년 9월 「노후계획도시 정비 및 지원에 관한 특별법」이 시행되자, 수도권 1기 신도시—분당, 일산, 평촌, 산본, 중동—의 아파트 가격은 어떻게 움직였을까? 더 구체적으로 묻자면, 정책 발표(2023년 2월 7일)부터 법률 공포(2024년 3월 24일), 시행(2024년 9월 15일)으로 이어진 3단계 과정에서 시장은 어느 단계에서 가장 민감하게 반응했을까. 그리고 정비 사업의 추진 단계나 단지마다 다른