Transit-oriented development (TOD) is best described as

compact, mixed-use, walkable development concentrated around a transit station, densest nearest it

a station surrounded by large park-and-ride car parks so that suburban motorists can reach the system easily

compact, mixed-use, walkable development concentrated around a transit station, densest nearest it

a bus corridor widened to carry more private vehicles at higher speeds between the suburbs and the centre

a single tall tower built beside a station, whose ground floor is closed to the street and to the station

A ‘complete street’ is one that

is designed for all users and modes, of all ages and abilities, not only for motor vehicles

is fully paved and lit, with a carriageway of uniform width along its entire length

gives priority to through traffic by removing on-street parking and signal-controlled crossings

is closed to all vehicles and reserved entirely for pedestrians at every hour of the day

is designed for all users and modes, of all ages and abilities, not only for motor vehicles

Floor area ratio (FAR), called floor space index (FSI) in India, is the

ratio of the total floor area of all counted floors of a building to the area of its plot

ratio of the area covered by the building at ground level to the area of its plot, as a percentage

ratio of the built-up area of a building to the carpet area of the dwelling units inside it

ratio of the area of the plot to the number of persons who will live or work in the building

A plot is subject to FAR 2.0, ground coverage of 40% and a height limit of four floors, every floor having the same area as the footprint. Which statement is correct?

The effective FAR is limited to 1.6, because four floors at 40% coverage use only 1.6 of the 2.0 permitted

The full FAR of 2.0 can be used, because five floors are always permitted when the FAR is 2.0 and the coverage is 40%

The effective FAR is 2.0, because the height limit is advisory and yields to the FAR limit when the two conflict

The effective FAR is limited to 1.6, because four floors at 40% coverage use only 1.6 of the 2.0 permitted

The effective FAR is 2.0 only if the footprint is enlarged to 50% by building into the setback area

A programme improves the houses, water supply, sanitation and lanes of an existing low-income settlement while its residents stay where they are and no area is cleared. In urban renewal terms this is chiefly

rehabilitation, because the existing fabric and residents stay and are improved

redevelopment, because the services of the settlement are rebuilt to a much higher standard

rehabilitation, because the existing fabric and residents stay and are improved

preservation, because the settlement is maintained exactly as it is without any improvement

reconstruction, because missing parts of the settlement are rebuilt using new material

In the usual conservation sense (as in the Burra Charter), which statement separates restoration from reconstruction?

Restoration uses only existing fabric, returning it to a known earlier state; reconstruction introduces new material to do so

Restoration rebuilds a lost building completely from old drawings and photographs; reconstruction only repairs the parts that survive on site

Restoration retards deterioration while keeping the present condition of the place; reconstruction adapts the place to a new use

Restoration applies only to isolated monuments in the open; reconstruction applies only to historic towns and urban areas

Which statement about the two documents called the ‘Athens Charter’ is correct?

The 1931 charter concerns the restoration of monuments; the 1933 charter, prepared by CIAM, proposes functional zoning

Both are concerned with the restoration of historic monuments and both were adopted at the same congress in 1931

The 1931 charter proposes the functional zoning of cities and the 1933 charter lays down principles for restoring monuments

The 1931 charter was adopted by ICOMOS, which was founded in that year to put its principles into practice

The 1931 charter concerns the restoration of monuments; the 1933 charter, prepared by CIAM, proposes functional zoning

A disused nineteenth-century textile mill of historic and architectural value is to be given a new life. Which approach best fits the principles of conservation and adaptive reuse?

Convert it to offices or a museum, keeping the structure and key spaces, with reversible, distinguishable new work

Demolish the mill and build a new structure behind an exact replica of its street façade, since that keeps the street image

Seal the building and keep it exactly as found, without any use, so that no fabric is ever altered

Convert it to offices or a museum, keeping the structure and key spaces, with reversible, distinguishable new work

Remove the machine hall and roof structure to make an open modern floor plate and keep only the street wall

Why do heritage regulations create a prohibited or regulated zone around a protected monument?

To protect the monument’s setting, physical and visual, from harmful construction nearby

To raise the land value of the surrounding plots by restricting the supply of building land

To make sure that the monument’s own fabric can be repaired, since repairs need an open work area

To collect a fee from each neighbouring owner who builds, so that the monument can be funded

To protect the monument’s setting, physical and visual, from harmful construction nearby

William H. Whyte’s observation of small urban plazas found that people used a plaza most where it offered

plenty of choice of places to sit, in sun and shade, near the street, with food available

a large ornamental fountain surrounded by a fence to keep people at a respectful distance

an uninterrupted lawn with a prominent notice requiring visitors to keep off the grass

a formal axial layout with symmetrical planting, kept free of furniture so as to look spacious

Which historical public space is correctly matched with its role?

The Indian ghat: a stepped waterfront used for bathing, ritual and daily social life

The Greek agora: a walled royal garden reserved for the ruler and the court

The Roman forum: an open market on the edge of the town, kept apart from civic buildings

The Indian ghat: a stepped waterfront used for bathing, ritual and daily social life

The English garden square: a commercial market street lined with shops on both sides

Which of the following pairings of a heritage or planning document with its concern are correct?

Venice Charter (1964): conservation and restoration of monuments and sites, with new work distinguishable from the original

Washington Charter (1987): conservation of historic towns and urban areas

Burra Charter (1979): a place is conserved on the basis of its cultural significance

Venice Charter (1964): conservation and restoration of monuments and sites, with new work distinguishable from the original

Washington Charter (1987): conservation of historic towns and urban areas

Burra Charter (1979): a place is conserved on the basis of its cultural significance

Athens Charter (1931): functional separation of living, working, recreation and circulation in the city

Which of the following statements about approaches to urban renewal are correct?

Rehabilitation improves existing buildings and services while keeping most of the existing fabric and community in place

Redevelopment normally involves clearing existing structures and building anew, so it causes the greatest disruption

Rehabilitation improves existing buildings and services while keeping most of the existing fabric and community in place

Redevelopment normally involves clearing existing structures and building anew, so it causes the greatest disruption

Retrofitting means demolishing a built-up area and rebuilding it on the same land at a higher FAR

Gentrification is a conservation technique that safeguards the housing of existing low-income residents

Which of the following statements about FAR and related development controls are correct?

Where a height limit applies, the floor area that can be built may be less than FAR multiplied by the plot area

Areas that the regulations exempt (for example certain parking or service areas) are not counted when FAR is worked out

Where a height limit applies, the floor area that can be built may be less than FAR multiplied by the plot area

Areas that the regulations exempt (for example certain parking or service areas) are not counted when FAR is worked out

FAR is the covered footprint of the building expressed as a percentage of the plot area

Gross density is the number of persons per hectare of residential plots alone

Interventions, Development Controls, Renewal, Heritage Conservation and Public Spaces

This is the second of two chapters on Part A, Section A.3, Urban Design and Conservation, of the Architecture and Planning (AR) paper. It answers the second half of the heading: “Urban design interventions for sustainable development and transportation; Development controls - FAR, densities and building byelaws; Urban renewal and conservation; Heritage conservation; Historical and contemporary public spaces”. It sets out transit-oriented development, complete streets, walkability and mixed use; the development controls (plot area, ground coverage, FAR, setbacks, height, density and the bye-laws) with their formulae; the approaches to urban renewal; the levels of conservation intervention, the main charters and the principle of legal protection, zones and listing; and the historical and contemporary public spaces. The numericals are floors under a coverage and FAR cap, the setback envelope with a height limit, gross and net density, transferable development rights and walking catchments.

1. Urban design interventions for sustainable development and transportation

Car-dependent cities use more land, energy and time. Urban design interventions for sustainable development work on urban form so that daily needs are close, the street is pleasant to walk and a high-capacity transit service is within reach of many people. The table lists the interventions the syllabus names.

Interventions for sustainable development and transportation
Intervention	Core idea	Typical measures
Transit-oriented development (TOD)	Concentrate compact, mixed-use, walkable development around high-capacity transit stations (the term was popularised by Peter Calthorpe)	Highest density and FAR nearest the station, a mix of homes, jobs and shops, short walkable blocks, limited parking, cycle and feeder links
Complete streets	Design every street for all users and modes, of all ages and abilities	Continuous footpaths, safe crossings, cycle lanes, bus priority, street trees, vending and seating zones, a lower design speed
Walkability	Make walking the easy, safe and pleasant choice for daily trips	The five Ds below, shaded and continuous footpaths, active frontages, lighting
Mixed use	Place homes, work, shops and services near one another, side by side or in the same building	Shops below homes, fine-grained plots, jobs–housing balance, shorter trips
Traffic calming and shared streets	Lower vehicle speed and let people share the carriageway	Raised crossings, chicanes, narrowed carriageways, speed tables; woonerf-type shared streets (the Netherlands, 1970s)
Compact, 15-minute neighbourhood	Daily needs within a short walk or cycle ride	Local centres, schools, clinics and parks within about a quarter of an hour on foot
Green infrastructure and microclimate design	Cool and drain the city through its public realm	Tree canopy, shaded streets, permeable paving, swales, orientation for breeze and shade

The ‘Ds’ of walkability and travel: Cervero and Kockelman’s three Ds were extended by Ewing and Cervero to five.
Density of people and jobs; diversity, the mix of uses.
Design of the street network and the pedestrian environment.
Destination accessibility, how many places can be reached; and distance to transit.

Walking catchments. A comfortable walking speed of 4.8 km/h is 80 m per minute, so a 5-minute walk is 400 m and a 10-minute walk is 800 m. A catchment drawn as a circle of radius 400 m has area π × 400² = 3.14 × 160,000 = 502,400 m², or 50.24 ha. At 800 m the radius doubles and the area quadruples, to about 201 ha. Real catchments are smaller than the circle because routes are not straight, so a network (street-distance) catchment is the better test than a radius.

⚠️ TOD or merely transit-adjacent?

A tower standing beside a station and a large car park is transit-adjacent development, not TOD. TOD needs a density gradient that falls away from the station, a mix of uses, walkable streets and restrained parking, so that the transit trip is the easy one.

ℹ️ TOD in Indian policy

India’s National TOD Policy (2017) of the Ministry of Housing and Urban Affairs promotes higher density and floor space close to mass-transit corridors, with mixed use and non-motorised access in a walkable influence zone. Learn the principle; the corridor distances and incentives are for the policy text, not for recall.

2. Development controls: ground coverage, FAR, setbacks and height

Development controls are the rules that decide what may be built on a plot and how much. They flow from the land-use zones of the Master Plan and Zonal Plan, are made legally binding through the State’s town planning and municipal laws, and are applied to each plot through the development control regulations and building bye-laws. The controls are quantities of bulk and open space, and they interlock. Numbers differ from city to city, so learn the relationships, which do not.

The main development controls
Control	What it is	What it protects
Plot area	Area of the plot, usually the net area after deductions such as land lost to road widening	The base on which every other ratio is computed
Ground coverage	(Area of the building footprint at plinth level ÷ plot area) × 100%	Open space, light, ventilation, drainage and tree planting
Floor area ratio (FAR), called floor space index (FSI) in India	Total floor area of all counted floors ÷ plot area	The bulk and intensity of use, and so the load on roads, water and sewerage
Setbacks	Minimum open distance kept between the building and the front, rear and side boundaries	Light, ventilation, privacy, fire access and future road widening
Height	Maximum height in metres or floors, often linked to the width of the abutting road and the setback	Light and air to the street, fire-fighting reach, skyline and enclosure
Open space and parking	Minimum open or green area; minimum parking for each unit of floor area	Environmental quality, and keeping vehicles off the street

Relations to remember. Permissible floor area = FAR × plot area. Floors needed to use it in full, when every floor equals the footprint, = FAR ÷ coverage (as a fraction). The footprint cannot exceed the smaller of the coverage cap and the envelope left after setbacks. Where a height limit applies, built-up area = the smaller of (FAR × plot area) and (footprint × floors allowed). A high FAR with low coverage forces a tall, slender building; a low FAR with high coverage gives a low, spread one.

Worked example. A plot of 20 m × 30 m = 600 m² has front, rear and side setbacks of 6 m, 3 m and 2.5 m each, a coverage cap of 40%, FAR 1.5 and a limit of three floors. Setback envelope = (20 − 5) × (30 − 9) = 15 × 21 = 315 m²; coverage cap = 0.40 × 600 = 240 m², which binds, so the footprint is 240 m². FAR gives 1.5 × 600 = 900 m², but three floors give only 3 × 240 = 720 m². Built-up area = the smaller, 720 m², an effective FAR of 1.2. Here the height limit, not FAR, is the binding control.

⚠️ FAR is not coverage, and not height

Coverage is a ground-level percentage; FAR counts all floors. A plot covered 100% at ground obeys FAR 2.0 with two floors, while the same FAR is met by a tower on 20% coverage or a low block on 60%. FAR is worked out on the net plot area, and the regulations list what is exempt from it (commonly some staircase, lift, parking and service areas); do not assume the exemptions, use the ones the question states.

🎯 Why height follows road width

Many bye-laws tie permissible height to the width of the road the plot faces and to the setback, through a height-to-width relationship or an angular plane. The principle is that tall buildings need wide streets, so that light, air, fire-fighting access and traffic capacity grow with the load. It is also the control that fixes the enclosure ratio (H/W) of the previous chapter.

3. Densities and building bye-laws

Density measures how intensely land is used, and each measure is defined by its denominator. Gross density divides by the whole planning unit, including roads, open spaces and community facilities; net (residential) density divides by the area of residential plots only, and is therefore always the higher. Density is counted in persons per hectare (pph) or dwelling units per hectare (DU/ha), with persons = DU × household size and 1 ha = 10,000 m².

Density and intensity measures
Measure	Divided by	Used for
Gross density	The whole area, roads, open space and facilities included	Planning at city or sector level: land budget and infrastructure
Net residential density	The area of the residential plots only	Housing layout and the built form of a neighbourhood
Dwelling units per hectare	Area, gross or net (always state which)	Counting housing supply, independent of household size
Floor area ratio	The plot area	The intensity of floor space on a plot

Worked example. A 40 ha neighbourhood has 1,600 dwelling units with a household size of 4.5, and 60% of its area is under residential plots. Population = 1,600 × 4.5 = 7,200. Gross density = 7,200 ÷ 40 = 180 pph (40 DU/ha). Residential plots = 0.60 × 40 = 24 ha, so net density = 7,200 ÷ 24 = 300 pph (66.7 DU/ha). The same neighbourhood is 180 or 300 persons per hectare; always state the denominator.

Building bye-laws are the legal rules, made by the local body under the State’s planning and municipal laws, that control construction at the level of the individual building. They carry the controls above and add rules on room sizes and ventilation, staircases and fire safety, parking, access for persons with disabilities, sanitation and rainwater harvesting. The Master Plan fixes the permitted land use of a plot; the regulations and bye-laws fix how much and how it may be built. A building plan is approved before work starts (commencement certificate) and the finished building is checked before use (occupancy or completion certificate). The National Building Code of India 2016 is the model technical code, and the model bye-laws of the Town and Country Planning Organisation guide the States.

⚠️ Density is not height

Density counts people or homes per area, not storeys. Five-storey perimeter blocks can reach densities that scattered towers in open space do not. And for the same area net density is always higher than gross density, so quoting a net figure against a gross standard is a classic error.

ℹ️ Transfer of development rights (TDR)

TDR lets an owner whose land is reserved for a road, a public use or heritage receive the unused development potential as a certificate that can be used on another plot. The owner is compensated without cash, the public use is secured, and development is moved elsewhere. Related tools are premium (paid) FAR and incentive FAR, which a city grants against payment or a public benefit such as affordable housing or heritage care.

4. Urban renewal: redevelopment, rehabilitation, conservation and retrofitting

Urban areas decay or become obsolete as buildings age, infrastructure falls behind, industries leave and uses change. Urban renewal is the umbrella term for the planned improvement of such areas, from clearing and rebuilding to gentle repair. The approaches differ in how much of the existing fabric and community they keep.

Approaches to urban renewal
Approach	What it does	Disruption	Examples
Redevelopment	Clears existing buildings and builds anew, often at higher density and with new uses	Highest	Haussmann’s Paris; London Docklands (former docks, from the 1980s)
Rehabilitation	Repairs and upgrades existing buildings and services in place while residents stay	Low to medium	In-situ upgrading of an informal settlement; repair of old housing stock
Conservation	Keeps and manages the valued fabric and character of an area and allows only sensitive change	Low	Historic cores and heritage precincts
Retrofitting	Adds or upgrades infrastructure, public realm, mobility and services in an existing built-up area, without wholesale rebuilding	Low to medium	The retrofitting option of area-based development in India’s Smart Cities Mission; energy retrofitting of buildings
Regeneration	Combined physical, economic and social renewal of an area, often built round one catalytic project	Varies	Bilbao and its Guggenheim museum; Seoul’s Cheonggyecheon stream; New York’s High Line

India’s Smart Cities Mission (2015) names three area-based development models: retrofitting (improving an existing area), redevelopment (replacing built-up area) and greenfield development (building on new land). HRIDAY, launched in 2015, was the national scheme for the development of heritage cities.

Start from what exists: conserve what has value, rehabilitate or retrofit what can be improved, and redevelop only what cannot. Disruption and cost rise in that order.
Questions to ask: the condition of the buildings, their heritage value, who lives there and what they want, financial feasibility and the capacity of the infrastructure.
Tools: in-situ upgrading, area-based plans, conservation and design guidelines, TDR and incentive FAR, and participation of residents from the start.

⚠️ Gentrification is not conservation

Renewal that raises rents and land values can push out the very residents it was meant to serve (Ruth Glass coined the term gentrification in 1964). It is a side-effect to be managed through tenure protection, affordable housing and local participation, not a conservation method. Jacobs’s attack on slum clearance made the same point: the displaced do not disappear, they are moved.

5. Heritage conservation: significance, principles and levels of intervention

Heritage conservation protects places of cultural significance: the aesthetic, historic, scientific, social or spiritual value a place holds for past, present and future generations (the wording of the Burra Charter). Heritage includes buildings, sites, historic towns and districts, cultural landscapes and living traditions. A sound process runs: record and understand the place, assess and state its significance, set a conservation policy, then manage and monitor. Intervention follows significance, never the reverse.

The doctrine grew out of a nineteenth-century quarrel. Viollet-le-Duc in France favoured restoring a building to a complete, stylistically pure state that may never have existed; Ruskin in Britain held that restoration destroys authentic fabric, and William Morris’s Society for the Protection of Ancient Buildings (1877) urged honest repair instead. Modern charters sit between the two: they respect original fabric and evidence, and allow limited, visible, reversible work.

Levels of intervention (definitions follow the Burra Charter)
Level	Meaning	Example of work
Conservation (the umbrella)	All the processes of looking after a place so as to retain its cultural significance; it may combine the levels below	The choice of level is made by significance and evidence
Maintenance	Continuous protective care of the fabric and setting; distinct from repair	Clearing gutters, renewing lime wash, removing vegetation
Preservation	Maintaining a place in its existing state and retarding deterioration	Stabilising a ruin and sheltering it, without completing it with new material
Restoration	Returning existing fabric to a known earlier state by removing accretions or reassembling existing components, without introducing new material	Taking off later additions; reassembling fallen original stones (anastylosis)
Reconstruction	Returning a place to a known earlier state by introducing new material	Rebuilding a destroyed part on the strength of documents or physical evidence, with the new work identifiable
Adaptive reuse (adaptation)	Modifying a place to suit a new or changed use while keeping its significance	A mill converted to offices; a haveli to a hotel or museum

Authenticity: respect for original fabric, design, materials and craftsmanship (the Nara Document of 1994 adds that it is judged within its cultural context).
Minimum intervention: do as much as is necessary and as little as possible.
Reversibility and distinguishable new work: new work should be removable without harming original fabric and identifiable on close inspection, yet harmonious with the whole; restoration stops where conjecture begins.
Documentation, setting and continuing use: record before, during and after work; the surroundings are part of the monument; a living use is the best guarantee of upkeep.

⚠️ Restoration, reconstruction and façadism

Restoration uses the existing fabric only; the moment new material is brought in to restore a lost element, the work is reconstruction. Adaptive reuse that keeps only the street façade and demolishes what lies behind (façadism) retains an image, not the significance of the place.

6. Charters, legal protection, heritage zones and listing

Charters are not statutes; they are professional consensus on which national laws and city regulations draw. Learn the year, the body and the one idea of each.

Principal heritage documents
Document	Year	Main concern
Athens Charter for the Restoration of Historic Monuments	1931	Regular maintenance, respect for the work of the past, the monument’s surroundings, modern techniques where needed, international cooperation
Athens Charter of CIAM (a planning document)	1933	Not about heritage: the functional city, with living, working, recreation and circulation kept apart
Venice Charter	1964	Conservation and restoration of monuments and sites: authenticity, respect for original material, restoration stops where conjecture begins, new work distinguishable, the setting is part of the monument; ICOMOS was founded the next year
UNESCO World Heritage Convention	1972	Cultural and natural heritage of outstanding universal value; the World Heritage List
Burra Charter (Australia ICOMOS)	1979 (revised 1999, 2013)	Significance-led conservation of a place: understand significance, set policy, then manage
Washington Charter (ICOMOS)	1987	Conservation of historic towns and urban areas
Nara Document on Authenticity	1994	Authenticity must be judged within its cultural context
INTACH Charter	2004	Conservation of unprotected architectural heritage and sites in India
UNESCO Recommendation on the Historic Urban Landscape	2011	A layered, integrated view of the historic city within its wider setting

In India, monuments of national importance are protected by the Archaeological Survey of India under the Ancient Monuments and Archaeological Sites and Remains Act, 1958 (the AMASR Act). Its 2010 amendment made the setting statutory: a prohibited area around a protected monument, in which construction is not allowed, and beyond it a regulated area, in which construction needs permission (100 m and a further 200 m in the amended Act). State archaeology departments protect monuments of state importance, and city heritage regulations list and protect the many buildings and precincts that the Act does not cover.

Listing is the formal identification of heritage assets after documentation and assessment; grading ranks them by significance so that the strictness of control follows value. Grade names and permitted changes differ from city to city, but in principle the highest grade (Grade I) covers buildings of national or exceptional importance, where only essential repair and sympathetic adaptive reuse are allowed; the middle grade covers regional or local importance, where careful alteration is allowed with approval; and the lowest grade protects townscape value, so that the external character is kept. A heritage zone (conservation area or precinct) extends control from single buildings to the area, governing height, materials and uses; incentives such as TDR, tax relief and extra FAR help owners bear the cost. World Heritage properties have a core zone and a buffer zone that protects the setting.

⚠️ Two Athens charters

The 1931 Athens Charter concerns the restoration of monuments; the 1933 Athens Charter of CIAM, published later by Le Corbusier, concerns the functional city. A question that mentions zoning into living, working, recreation and circulation is about 1933, the planning document, whatever the word ‘Athens’ suggests.

7. Historical and contemporary public spaces

Public space is the part of the city open to everyone: streets, squares, parks, waterfronts and markets. Its history is the history of what cities did in the open: trade, ritual, assembly and play.

Public spaces through history
Period or type	Public space	Role and character
Greek	The agora	An open civic, commercial and social centre bordered by colonnades (stoas)
Roman	The forum	The civic, religious and commercial heart, set where the main streets cross
Medieval to early modern	Market square and piazza (Piazza del Campo, Siena; the Campidoglio, Rome; Place des Vosges, Paris, 1612)	Enclosed urban rooms for markets, ceremony and display; the later squares are designed compositions
Traditional Indian	Chowk, ghat, temple tank and mandapa, bazaar street, baoli, village chaupal, maidan	Multi-use, ritual and commercial spaces; the street itself is market and festival ground
Nineteenth century	Public park and boulevard (Birkenhead Park, 1847; Central Park, New York, Olmsted and Vaux, 1858)	The park as a civic amenity for health and recreation
Modernist twentieth century	Plaza at the foot of a tower; privately owned public space (POPS)	Often open but windswept and empty; New York’s 1961 zoning gave floor-area bonuses for public plazas
Contemporary	Pedestrianised streets (Strøget, Copenhagen, 1962), waterfront parks (Sabarmati Riverfront), reclaimed infrastructure (High Line, Cheonggyecheon), parklets and tactical urbanism	Road and rail space given back to people; low-cost, temporary experiments

William H. Whyte’s observations of New York plazas (The Social Life of Small Urban Spaces, 1980) found that people use a plaza where there is somewhere to sit (ledges, steps, movable chairs), sun, trees and water, food, and a link to the street so that the place can be seen from outside; and that strangers mix where something draws them together, which he called triangulation (a sculpture, a performer). Jan Gehl separates necessary activities (which happen in any space), optional activities (which happen only if the place is pleasant) and social activities (which depend on others being present); good design mostly raises the second and third. Ray Oldenburg called the informal gathering places beyond home and work ‘third places’: cafés, tea stalls, the village chaupal.

Access and inclusion: women, children, the elderly, persons with disabilities and street vendors must be able to use the space.
Privatisation: shopping malls, gated plazas and privately owned public spaces are open only on conditions the owner sets.
Safety through natural surveillance by users and active edges, rather than through fences.
Management and comfort: programming, maintenance, room for informal use, and shade, water and seating for the climate.

⚠️ Public does not mean publicly owned

Ownership, access and management are three different things. A privately owned plaza can be fully public in use, and a publicly owned park can be effectively closed by fees or fences. The test in a question is who may use the space and on what terms.

Key takeaways

TOD concentrates density, mixed use and walkable streets around transit; complete streets serve all users; the Ds of walkability are density, diversity, design, destination accessibility and distance to transit; a 5-minute walk at 4.8 km/h is 400 m.
Permissible floor area = FAR × plot area; floors at full use = FAR ÷ coverage; built-up area = the smaller of the FAR limit and footprint × floors allowed, so a height cap can be the binding control.
Net density exceeds gross density for the same area (state the denominator); persons = DU × household size; TDR moves unused development potential from reserved or heritage land to another plot.
Renewal runs from redevelopment (most disruptive) through retrofitting and rehabilitation to conservation; gentrification is a side-effect to manage, not a conservation method.
Preservation keeps the present state; restoration uses existing fabric only; reconstruction brings in new material; adaptive reuse gives a new use. The charters share the principles of authenticity, minimum intervention, reversibility and distinguishable new work.
Keep the charters straight: Athens 1931 (monuments) against Athens 1933 (functional city), Venice 1964, Burra 1979, Washington 1987 (historic towns); remember prohibited and regulated areas protect a monument’s setting, and that public space is about access, not ownership.

Practice questions (20)

Attempt each one before opening the answer. Every explanation names the tempting wrong option as well as the right one, because that is where marks are lost.

Transit-oriented development (TOD) is best described as
1. a station surrounded by large park-and-ride car parks so that suburban motorists can reach the system easily
2. compact, mixed-use, walkable development concentrated around a transit station, densest nearest it
3. a bus corridor widened to carry more private vehicles at higher speeds between the suburbs and the centre
4. a single tall tower built beside a station, whose ground floor is closed to the street and to the station
Show answer
Answer: B — compact, mixed-use, walkable development concentrated around a transit station, densest nearest it
TOD concentrates density, a mix of uses and walkable streets around a transit station, with the highest intensity nearest it and restrained parking. Park-and-ride lots and an isolated tower with a blank ground floor are merely transit-adjacent: they sit by the station without making the transit trip the easy one.
A ‘complete street’ is one that
1. is fully paved and lit, with a carriageway of uniform width along its entire length
2. gives priority to through traffic by removing on-street parking and signal-controlled crossings
3. is closed to all vehicles and reserved entirely for pedestrians at every hour of the day
4. is designed for all users and modes, of all ages and abilities, not only for motor vehicles
Show answer
Answer: D — is designed for all users and modes, of all ages and abilities, not only for motor vehicles
A complete street is designed to serve pedestrians, cyclists, transit users and motorists of all ages and abilities. A fully pedestrianised street serves only one mode, which is the tempting overcorrection; a complete street still carries vehicles, but not at the expense of everyone else.
Floor area ratio (FAR), called floor space index (FSI) in India, is the
1. ratio of the total floor area of all counted floors of a building to the area of its plot
2. ratio of the area covered by the building at ground level to the area of its plot, as a percentage
3. ratio of the built-up area of a building to the carpet area of the dwelling units inside it
4. ratio of the area of the plot to the number of persons who will live or work in the building
Show answer
Answer: A — ratio of the total floor area of all counted floors of a building to the area of its plot
FAR (FSI) = total counted floor area ÷ plot area, so a plot of 500 m² with FAR 2 may carry 1,000 m² of floor area. The ground-level percentage in the tempting alternative is ground coverage, a different control that looks at one floor only.
A plot is subject to FAR 2.0, ground coverage of 40% and a height limit of four floors, every floor having the same area as the footprint. Which statement is correct?
1. The full FAR of 2.0 can be used, because five floors are always permitted when the FAR is 2.0 and the coverage is 40%
2. The effective FAR is 2.0, because the height limit is advisory and yields to the FAR limit when the two conflict
3. The effective FAR is limited to 1.6, because four floors at 40% coverage use only 1.6 of the 2.0 permitted
4. The effective FAR is 2.0 only if the footprint is enlarged to 50% by building into the setback area
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Answer: C — The effective FAR is limited to 1.6, because four floors at 40% coverage use only 1.6 of the 2.0 permitted
Four floors at 40% coverage give 4 × 0.40 = 1.6 of plot area, below the FAR of 2.0; a fifth floor would be needed to reach 2.0 and the height limit forbids it. The coverage cap and the setbacks also bar the enlargement of the footprint, so the height limit, not FAR, is the binding control.
A programme improves the houses, water supply, sanitation and lanes of an existing low-income settlement while its residents stay where they are and no area is cleared. In urban renewal terms this is chiefly
1. redevelopment, because the services of the settlement are rebuilt to a much higher standard
2. rehabilitation, because the existing fabric and residents stay and are improved
3. preservation, because the settlement is maintained exactly as it is without any improvement
4. reconstruction, because missing parts of the settlement are rebuilt using new material
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Answer: B — rehabilitation, because the existing fabric and residents stay and are improved
Upgrading buildings and services in place, with residents staying, is rehabilitation (in-situ upgrading). Redevelopment would clear and rebuild, which is the tempting answer because services are also improved; preservation would stop deterioration without improving anything, and reconstruction belongs to heritage work.
In the usual conservation sense (as in the Burra Charter), which statement separates restoration from reconstruction?
1. Restoration uses only existing fabric, returning it to a known earlier state; reconstruction introduces new material to do so
2. Restoration rebuilds a lost building completely from old drawings and photographs; reconstruction only repairs the parts that survive on site
3. Restoration retards deterioration while keeping the present condition of the place; reconstruction adapts the place to a new use
4. Restoration applies only to isolated monuments in the open; reconstruction applies only to historic towns and urban areas
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Answer: A — Restoration uses only existing fabric, returning it to a known earlier state; reconstruction introduces new material to do so
The dividing line is new material: restoration works with what exists (removing accretions or reassembling original pieces), while reconstruction brings in new material to return to a known earlier state. The statement that has restoration rebuilding a lost building completely reverses the two, which is the tempting error, and the remaining two describe preservation and adaptation.
Which statement about the two documents called the ‘Athens Charter’ is correct?
1. Both are concerned with the restoration of historic monuments and both were adopted at the same congress in 1931
2. The 1931 charter proposes the functional zoning of cities and the 1933 charter lays down principles for restoring monuments
3. The 1931 charter was adopted by ICOMOS, which was founded in that year to put its principles into practice
4. The 1931 charter concerns the restoration of monuments; the 1933 charter, prepared by CIAM, proposes functional zoning
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Answer: D — The 1931 charter concerns the restoration of monuments; the 1933 charter, prepared by CIAM, proposes functional zoning
The 1931 Athens Charter for the Restoration of Historic Monuments is a heritage document; the 1933 Athens Charter prepared by CIAM (published later by Le Corbusier) is a planning document on the functional city. Swapping the two subjects is the tempting error, and ICOMOS was founded only in 1965, after the Venice Charter of 1964.
A disused nineteenth-century textile mill of historic and architectural value is to be given a new life. Which approach best fits the principles of conservation and adaptive reuse?
1. Demolish the mill and build a new structure behind an exact replica of its street façade, since that keeps the street image
2. Seal the building and keep it exactly as found, without any use, so that no fabric is ever altered
3. Convert it to offices or a museum, keeping the structure and key spaces, with reversible, distinguishable new work
4. Remove the machine hall and roof structure to make an open modern floor plate and keep only the street wall
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Answer: C — Convert it to offices or a museum, keeping the structure and key spaces, with reversible, distinguishable new work
Adaptive reuse keeps the significant structure and spaces while giving a viable new use, with new work that is reversible and identifiable. Keeping only the street wall or an exact replica of the façade (façadism) retains an image but destroys the significance, and sealing the building unused invites decay because a living use is the best guarantee of upkeep.
Why do heritage regulations create a prohibited or regulated zone around a protected monument?
1. To raise the land value of the surrounding plots by restricting the supply of building land
2. To make sure that the monument’s own fabric can be repaired, since repairs need an open work area
3. To collect a fee from each neighbouring owner who builds, so that the monument can be funded
4. To protect the monument’s setting, physical and visual, from harmful construction nearby
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Answer: D — To protect the monument’s setting, physical and visual, from harmful construction nearby
Conservation treats the setting as part of the monument, so construction nearby is barred or regulated to protect its physical surroundings and its views. Working space for repairs and fee income are by-products at most, and raising land values is not a purpose of the law.
William H. Whyte’s observation of small urban plazas found that people used a plaza most where it offered
1. plenty of choice of places to sit, in sun and shade, near the street, with food available
2. a large ornamental fountain surrounded by a fence to keep people at a respectful distance
3. an uninterrupted lawn with a prominent notice requiring visitors to keep off the grass
4. a formal axial layout with symmetrical planting, kept free of furniture so as to look spacious
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Answer: A — plenty of choice of places to sit, in sun and shade, near the street, with food available
Whyte found that the best-used plazas offered sitting space (including movable seating), sun, trees and water, food and a link to the street. Fenced fountains, keep-off lawns and bare formal layouts all discourage use, and the formal layout is the tempting choice because it looks impressive on a drawing.
Which historical public space is correctly matched with its role?
1. The Greek agora: a walled royal garden reserved for the ruler and the court
2. The Roman forum: an open market on the edge of the town, kept apart from civic buildings
3. The Indian ghat: a stepped waterfront used for bathing, ritual and daily social life
4. The English garden square: a commercial market street lined with shops on both sides
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Answer: C — The Indian ghat: a stepped waterfront used for bathing, ritual and daily social life
A ghat is a stepped bank where bathing, ritual and daily social life meet. The agora was the open civic, commercial and social centre of a Greek town, the forum stood at the heart of a Roman town where its main streets crossed, and an English garden square is an enclosed residential green, not a market street.
Which of the following are among the ‘D’ variables (density, diversity, design and others) used to explain how built form affects walking and travel?
1. Destination accessibility
2. Decentralisation
3. Distance to transit
4. Dispersal
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Answer: A — Destination accessibility; C — Distance to transit
The Ds are density, diversity and design (Cervero and Kockelman), to which Ewing and Cervero added destination accessibility and distance to transit. Decentralisation and dispersal are not among them; if anything, they describe the sprawl that the Ds are meant to counter.
Which of the following pairings of a heritage or planning document with its concern are correct?
1. Venice Charter (1964): conservation and restoration of monuments and sites, with new work distinguishable from the original
2. Washington Charter (1987): conservation of historic towns and urban areas
3. Burra Charter (1979): a place is conserved on the basis of its cultural significance
4. Athens Charter (1931): functional separation of living, working, recreation and circulation in the city
Show answer
Answer: A — Venice Charter (1964): conservation and restoration of monuments and sites, with new work distinguishable from the original; B — Washington Charter (1987): conservation of historic towns and urban areas; C — Burra Charter (1979): a place is conserved on the basis of its cultural significance
The Venice, Washington and Burra charters are paired correctly. The functional separation of living, working, recreation and circulation belongs to the 1933 Athens Charter of CIAM; the Athens Charter of 1931 is about the restoration of historic monuments.
Which of the following statements about approaches to urban renewal are correct?
1. Rehabilitation improves existing buildings and services while keeping most of the existing fabric and community in place
2. Redevelopment normally involves clearing existing structures and building anew, so it causes the greatest disruption
3. Retrofitting means demolishing a built-up area and rebuilding it on the same land at a higher FAR
4. Gentrification is a conservation technique that safeguards the housing of existing low-income residents
Show answer
Answer: A — Rehabilitation improves existing buildings and services while keeping most of the existing fabric and community in place; B — Redevelopment normally involves clearing existing structures and building anew, so it causes the greatest disruption
Rehabilitation keeps fabric and community in place, and redevelopment clears and rebuilds, which is the most disruptive. Retrofitting improves an existing built-up area without wholesale rebuilding, so demolition at a higher FAR is redevelopment, and gentrification is a side-effect that displaces low-income residents, not a way of protecting them.
Which of the following statements about FAR and related development controls are correct?
1. Where a height limit applies, the floor area that can be built may be less than FAR multiplied by the plot area
2. Areas that the regulations exempt (for example certain parking or service areas) are not counted when FAR is worked out
3. FAR is the covered footprint of the building expressed as a percentage of the plot area
4. Gross density is the number of persons per hectare of residential plots alone
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Answer: A — Where a height limit applies, the floor area that can be built may be less than FAR multiplied by the plot area; B — Areas that the regulations exempt (for example certain parking or service areas) are not counted when FAR is worked out
A height or coverage cap can leave part of the permitted FAR unused, and exempted areas are left out of the FAR count. The footprint as a percentage of the plot is ground coverage, not FAR, and density measured on residential plots alone is net density, because gross density divides by the whole planning area.
A plot of 24 m × 30 m has a permissible ground coverage of 35% and a FAR of 1.75. If every floor has the same area as the footprint and the permissible floor area is used in full, the number of floors is ____.
Numerical answer — type the value.
Show answer
Answer: 5
Plot area = 24 × 30 = 720 m². Footprint = 0.35 × 720 = 252 m². Permissible floor area = 1.75 × 720 = 1,260 m². Floors = 1,260 ÷ 252 = 5; equivalently FAR ÷ coverage = 1.75 ÷ 0.35 = 5. Using 35 instead of 0.35 would give a meaningless 0.05.
A plot of 20 m × 30 m must keep a front setback of 6 m, a rear setback of 3 m and side setbacks of 2.5 m each. Ground coverage is capped at 40% and FAR at 1.5, and the building may have at most 3 floors, each equal in area to the footprint. The maximum built-up area (total floor area) that can be built, in m², is ____.
Numerical answer — type the value.
Show answer
Answer: 720
Plot = 600 m². Setback envelope = (20 − 2.5 − 2.5) × (30 − 6 − 3) = 15 × 21 = 315 m²; coverage cap = 0.40 × 600 = 240 m², so the footprint is at most 240 m². FAR limit = 1.5 × 600 = 900 m²; height limit = 3 × 240 = 720 m². The smaller of 900 and 720 is 720 m². Taking the 900 m² FAR figure alone ignores the floor limit.
A neighbourhood of 40 ha (gross) has 1,600 dwelling units with an average household size of 4.5 persons. Residential plots occupy 60% of the area. The net residential density, in persons per hectare, is ____.
Numerical answer — type the value.
Show answer
Answer: 300
Population = 1,600 × 4.5 = 7,200 persons. Residential plot area = 0.60 × 40 = 24 ha. Net density = 7,200 ÷ 24 = 300 persons per hectare. Dividing by the whole 40 ha gives the gross density, 180, which is the tempting wrong answer.
A heritage building stands on a plot of 800 m² where FAR 2.0 is permitted. The building has 500 m² of floor area and may not be enlarged. Under a scheme in which all the unused permissible floor area can be transferred to another site as transferable development rights (TDR), the TDR that the owner can receive, in m² of floor area, is ____.
Numerical answer — type the value.
Show answer
Answer: 1100
Permissible floor area = 2.0 × 800 = 1,600 m². Existing floor area = 500 m². Unused potential = 1,600 − 500 = 1,100 m², which is the TDR receivable. Taking the whole 1,600 m² would ignore what the heritage building already uses.
A TOD planner defines the catchment of a station as a circle whose radius is the distance walked in 5 minutes at 4.8 km/h. Taking π = 3.14, the catchment area, in hectares, correct to two decimal places, is ____.
Numerical answer — type the value.
Show answer
Answer: 50.24
Radius = 4.8 km/h × (5/60) h = 0.4 km = 400 m. Area = 3.14 × 400² = 3.14 × 160,000 = 502,400 m². Dividing by 10,000 gives 50.24 ha. Taking 800 m (a 10-minute walk) as the radius would give four times the area, about 201 ha.