BUILDING RESEARCH INSTITUTE

Urban Planning for aDepopulating Society
Japan’s Building Research Institute is researching and developing residential and urban planning methods
that take account of regional characteristics in an effort to counter the effects of depopulation.

A

ccording to demographic
statistics for 2005, Japan is
rapidly becoming a depopulating society with the firstnatural attrition since records began.
Because of longevity and low birthrates,
the percentage of the aging population
has reached 20% of the total population.
This is already the highest in the world.
In the future, the rate of population decrease will remain at maximum levels
for an advanced nation and by 2050 theproportion of the elderly is projected to
be double what it is now (see figures 1and 2). As for the economy, the expectation is for no growth or contraction.
Taking into account the increase inglobal environmental problems as well,there will be major changes in the social

environment surrounding residential andurban planning.
In this context, we are presented
with problems such as the hollowing
out of central areas, primarily in local
towns and cities. It is already difficult
to implement conventional development methods aimed at upgrading land
use and with the decline in public finance reserves for state and local publicbodies, we are in a situation where itis difficult to expect improvements inpublic services. Therefore, it is necessary to rebuild systems to support urbanplanning, to develop residential andurban planning methods including proactive participation by local residents’organizations such as neighborhood association, and to share roles appropri-Figure 1: Population increases and decreases inAsia and the West22

ately between public and private sectors
while utilizing regional resources suchas the housing stock and townscapes.
In response to these socioeconomicchanges, the Building Research Instituteis researching and developing residential
and urban planning methods that takeaccount of regional characteristics.
Present Situation in Urban Centers
in Regional Towns and Cities

Many of the central areas of local cities
are residential areas with a concentration of low-rise detached housing andthere are many small lots of approximately 100 m2. When the elderly residents of housing built on such small
lots die, the children inherit the lots,

Figure 2: Proportion of aging population (ratio ofpopulation aged 65 and over) in Asia and the West

Figure 3: Parking lots are increasing in residential areas.

Figure 5: Underused and unused land in an urban
city center<2003><2007>

Figure 4: A medium-rise apartment building built in a low-rise
residential area

owners and thesupply forresidential
needs is extremely limited.

Fukurogawa
River

Minami-machi
Ima-machi

Source: Tottori city researchbut many people in the children’s generation are leaving for the major cities
and the houses and land are soon vacant. In this way, there is an ongoinghollowing out of the central areas inlocal cities with vacant lots, parking
lots and other underused or unused land
becoming more common, while theconstruction of medium to high-riseapartment buildings is advancing whencomparatively large lots are sold to developers, causing the destruction of thetownscape and becoming something of
an issue (figures 3–5).
In these circumstances, as the population continues to age, there is a
growing need for housing in areas
where it is possible to get around on
foot (figure 6). However, in the centersthere is a strong awareness of continuous property holding among land-Aiming for
Dynamic andComfortable
Urban
Planning

Utilizing regional resources, residential
and urban planning methods
Vacant lots
suited to regionMonthly parking
Hourly parking
al characterisCentral area
tics, and the roleof people in thecommunity are the key points for redressing the hollowing out of city centers caused by the population decline,
revitalizing housing in downtown areas
and upgrading and maintaining regional
residential space. As for specific methods, we propose the following.
(1) The need to develop effective
land use techniques to replace
downtown parking lots
Low-rise residential models
suitable for dowtown areas inlocal and cities and methods fortheir realization
Parking lot landowners in urban city
centers place a high value on parking
lots as a hassle-free method of asset(land) ownership (figure 7 ). It is also
clear that as matters now stand, nomethod for effective land use to replaceparking lots has been found. With regard
to this situation, major contributions torevitalizing urban city centers and facilitating downtown living are conceivable,
if it were possible to develop methods
for supplying housing while retaining
ownership of the land as a method ofland use that could replace parking lots.
(2) Potential for a method utilizing
leaseholds
Verification by means of model
design and project simulation
As a method of delivering low-risehousing in central area in local cities, westudied the potential for land use utilizing leaseholds (a lease with a term ofat least fifty years and, as a rule, notrenewable) in Tottori City (figure 8).
Typically, housing with leaseholds
has materialized because, comparedwith the usual subdivision method,
the land is ultimately not retained andthe price is said to be 80% or less of acondominium (ownership of land).
Preliminary calculations by the Building
Research Institute based on the example
of a leasehold for a model-designed,
low-rise connected house format (terraced houses) found that they wereavailable at 80% or less of the price ofthe normal subdivision method. Basedon this, there is potential to establish
low-rise housing with leasehold rights
since they seem to be undervalued incontrast with normal condominiums(ownership of land) (figure 9).
As a result of the preliminary calculations, we also found that with respect to profitability for the landowner,
low-rise housing with a leasehold secures profitability that is equivalent to23

BUILDING RESEARCH INSTITUTE
Figure 6: Reasons for wanting to live
Figure 7: Reasons for owners to use land as
operating aintheurban
city
centerparking lotsparking lot(figure 10).
As forHassle-free maintenanceEasy access to hospitals, public offices
medium toand other facilities
high-rise
Want to retain as asset
housing with
Convenient for everyday shopping
No other lucrative useleaseholds,
the results of
A parking lot can be converted
Commuting to work andthe prelimiat any timeschool is convenient
nary calculaStable demand for parking lotsmeans high returns
Worried about the time when I cantions indicate
no longer drive in the suburbs
Cannotsell land for athat there issatisfactory priceno market
Easy to enjoy culture
No tenants for landand entertainment
from theperspective ofSeems easy to manage even without
Other
homebuyers
relations with the neighborhoodand landownNo response
ers in local
Other
cities wherethe price ofNo response
land is low.
It is possible to purchase housing with a term leasehold for ing parking lots is relatively high. As residential environment emerges. Whenless than the normal condominium be- matters now stand, if revenue were these areas are neglected, there is notcause the share of land expense is low. equal, we believe that the potential is only an increase in collapse and otherTherefore, when land prices are low, the still high for choosing to operate a park- dangers, but there is also emerging
price difference with normal condomini- ing lot due to the liquidity of the land. concern that they are becoming breedums is diminished and from the perspec- Therefore, in order to find ways to pro- ing grounds for criminal activity. With
tive of the buyer, the advantage is lost. mote downtown living with low-rise regard to such vacant lots and houses,
On the other hand, profits are also low housing suited to the central areas of a structure is required that assumes thefor landowners because they cannot set local cities, it would be effective to role of managing such information
combine measures such as preferential c e n t r a l l y , m a k i n g i m p r o v e m e n t s
a high ground rent.
treatment for fixed asset taxes involving through repairs, and proposing meth(3) The need for a combination ofownership of housing and land, and ods of utilization through shared use
support systems for downtown
urban planning control, including height with adjoining land.
housing and urban planning
As a method for regional space imregulations that consider the townscape.
regulation
provement, assuming the pattern of basic
land use and space improvement outlined
In local cities, the revenue from operat- (4) Methods to improve space in theregions andin figure 11, we propose improvement
management ofmethods to connect building lots with novacant lots andaccess to roads to the road network, tohousingmaintain the facilities and infrastructure
In areas where elements that are necessary for the region
there is a con- such as new turning roads for automoc e n t r a t i o n o f biles using existing unused land, ims m a l l - s c a l e provement methods utilizing adjoiningb u i l d i n g l o t s , vacant houses and unused building lots,
management of and methods of utilizing existing vacantvacant lots and housing based on characteristics such asvacant housing the state of road-to-lot connections andis inadequate, the degree of obsolescence of the builda n d a s v a c a n t ings. By utilizing these types of improvehousing contin- ment patterns to reorganize the space,ues to deterio- unused land in a bad state of repair andrate, damage to dwelling density will be reduced with theFigure 8: Downtown low-rise housing model
the surrounding effect of improving the standard of the24Figure 9: Price comparison for housing withterm leasehold and normal condominiums(land ownership)

Figure 10: Comparing annual revenue forlandowners
It is clear that only low-rise housing with leasehold iscapable of securing profitability that is roughly equal tooperating a parking lot.

It is alleged that for housing with leaseholds to materialize,
the ratio to subdivision is 80% or less. It is clear that this issatisfied by low-rise housing.

Ratio to subdivision =Price for housing with leasehold
million yen
2.4

Price for normal condominium

million yen
50

Housing price

Ratio to subdivision

40
35
30
25
2015

Annual revenue

2.35

45

2.32

2.252

2.202

10
50

2.15

parkingHigh-rise 80 m2

Housing price(land ownership)

Medium-rise 80 m2

Housing price(leasehold)

Low-rise 125 m2

Leasehold
Leasehold
Leaseholdhigh-rise 80 m2 medium-rise 80 m2 low-rise 125 m2

Ratio tosubdivision

Figure 11: Pattern for basic land use and space improvement (example)

pation of neighborhood associations
Put vacant houses connected to a road underTemporaryand other commuTenanted
Vacanttemporary management and advertise formanagementnity associations
tenants after renovation.
is thought to work
well for residential
Remove vacant houses that are not connected toNot Connected
Not Connected
Not Connecteda road, and advertise for people to use the lots toand urban planning
Vegetable
VacantRemovalplotgrow vegetables.
under depopulation.
With respect toAfter removing vacant houses on back lots notConnected
Not Connected
Connected
the residential andconnected to roads, consolidate the lots and use
Vegetable
VacantResidence
Residenceurban planningplot
as a single vegetable plot (garden).
methods proposedand studied in the
Remove vacant houses connected to roads,
Connected
Not Connected
Connected
past, the Building
consolidate unused vacant land at the back andUnusedNew build
Vacantbuild new housing.
vacant land
Research Institutewill continue toRemove vacant houses, consolidate unused vacantstudy the potential
Connected
Not Connected
Notland at the back, and improve conditions for road
Connected
for implementation
Parking lot
VegeVacant
Residence Unusedconnection by turning the frontage into
Residencetablevacant
through trials inplot
parking space.
land
Connected
model zones aswell as making
Use parking lots and unused vacant land to build
Connected
Connected
Not Connected Not Connected
Block parking lot
broad studies of the
new turning roads with remaining land operated
UnusedUnusedNew
Parking lotvacantvacantbuildas a block parking lot by the community association,
potential for appliland
land
Turning roadand build new housing on land where the conditions
cations in otherfor connection to roads have been improved.
areas. In a few decades, the develspace improvement patterns and meth- oped nations in Europe, China and Korea
residential environment.
ods for implementing low-rise housing will also be faced with aging societies
Toward the Future
in downtown areas in local cities and similar to Japan, and we believe there
towns introduced earlier, implementa- will be an increase in opportunities toWith respect to the application of basic tion by bringing in the proactive partici- utilize this kind of expertise.
Connected

Connected

Connected

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