4.
Knowledge Integration
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
4.1 KIT3
the value of urban centres
Prof Bill Hillier
UCL
Martin Wedderburn
Buchanan
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
Every Centre has a centre
the space syntax theory of centre formation in cities
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
Space Syntax theory of centres
•
•
•
•
iValul
Every centre has a centre. It starts with a spatial seed, usually an
intersection, but it can be a segment.
The seed of a centre will have destination and route values at both
local and global levels.
Some centres start because they are the focus of a
local intensified grid – a local case – other because they are at an
important intersection – a global case. Both global and local
properties are relevant to how centres form and evolve.
The spatial values of the seed for the centre will establish what we
can call a fading distance from the seed. Up to what distance from
the seed will shops be viable ? This is a function of metric distance
from the seed proportionate to the strength of the seed.
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge integration KIT3 Centres
Local Choice R400
Local centre starts at
southern end of
Streatham High
Street.
10
6
274
Choice R400 (Streatham model)
458
Mid Term Event
i-VALUL the intangible value of urban layout
Accessibility
high
low
UrbanBuzz
© Space Syntax 2008
4.1 London high streets Streatham High Road Choice R800
Local centre starts at
southern end of
Streatham High
Street…
…. and shifts
gradually to the North
towards a more global
radius
2842
3379
Choice R800 (Streatham model)
3153
Mid Term Event
i-VALUL the intangible value of urban layout
Accessibility
high
low
UrbanBuzz
© Space Syntax 2008
4.1 London high streets Streatham High Road Choice R1200
Local centre starts at
southern end of
Streatham High
Street…
…. and shifts
gradually to the North
towards a more global
radius
10200
11235
Choice R1200 (Streatham model)
9800
Mid Term Event
i-VALUL the intangible value of urban layout
Accessibility
high
low
UrbanBuzz
© Space Syntax 2008
4.1 London high streets Streatham High Road Choice R1400
Local centre starts at
southern end of
Streatham High
Street…
15500
…. and shifts
gradually to the North
towards a more global
radius
15900
The best fitting radius
with the retail
definition of the high
street is R1400.
Choice R1400 (Streatham model)
15622
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 London high streets Streatham High Road Choice RN
Choice RN (Streatham model)
Streatham High Street
not highest global
choice route in the
area
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
•
The centre will grow beyond the fading distance established by the initial
seed to the degree that further seeds appear within the fading distance.
Again these can be local or global, and stronger or weaker. A centre
becomes larger to the degree that it is reinforced by what are in effect new
seed which allow the shopping to be continuous.
•
Centres expand in two ways:
– linearly, that is along a single alignment or two intersecting alignments. This is
the most common case. Linear expansion occurs when the reinforcers are
more or less orthogonal or up to 45 degrees to the original alignment
– convexly, that is the shopping streets form a localised grid, which is rarer, but
great when it occurs. Convex expansion occurs when reinforcers occur on the
parallel as well as the orthogonal alignment
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
•
So centres vary in the strength of their local and global properties, and the
balance between them will tend to define the nature of the centre. Most
centres will tend to be pretty strong both in local and global terms, but
differences in the balance will be very influential in generating the scale
and character of the centre.
•
Centres also grow or fail through interaction with neighbouring centres at
different scales, but the way in which the urban grid evolves tends to
ensure that seeds for potential centres occur only at certain distances from
each other. We need to account for the spatial factors if we are to really
understand the ways in which centres interact with each other.
•
Apply and verify the Space Syntax theory on a set of well studied centres
(CABE/Buchanan 2007, Paved with Gold)
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Hampstead
Kilburn
Swiss Cottage
West Ealing
Walworth Rd
Chiswick
log Choice RN
Clapham
Tooting
Mid Term Event
i-VALUL the intangible value of urban layout
Streatham
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
Key questions:
A. Are centres spatially distinguishable from non-centres?
B. Is there a typology of centres?
C. What is the relationship between the centre and its context?
D. What spatial factors are a component of the value of centres?
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Cl
ap
ha
m
Ro
ad
A. Centre - non-centre
am
Centre
ph
am
Non-centre
Cla
log Choice R 2000m
`Co
mm
on
So
uth
Si d
e
h
ap
Cl
gh
Hi
et
re
t
S
Non-centre
We take the main high
street (centre)
and compare it with its
linear extension to both
sides (non-centre).
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
A. Centre - non-centre
We compare centres and non-centres on a series of spatial
variables.
If the theory is right, we would expect that:
1. Centres have shorter segment lengths
2. Centres have higher local choice (path overlap)
3. The differences between centres and non-centres on choice will
disappear as we increase the radius from local to global
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
Segment Length
What do we find?
i-VALUL
iValul
160
Variables
1. In all cases, centres have shorter segment 140
lengths that non-centres, on average by
120
about 40% - a remarkably clear result
100
80
Non-Centre
60
40
1.
Centre
Observations
segL
max
segL
av
ch300
Ch 400
Ch 800
Ch 2000
Ch10,000
n
Centres
155.9
56.9
156.2
356.7
5632.4
9,3441
31,107,168
2,502,094,571
Noncentres
248.7
93.7
90.6
212.0
4,366.9
8,3634
32522119
2,502,215,728
%
difference
-39%
-39%
+72%
+68%
+29%
+12%
-4.5%
0.0%
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
Non-Centre
iValul
Regression Plot
2.25
Segment length for
centres against
non-centres covary, so there is a
local segment
length context.
2.2
logNC-seglenthAV
2.15
2.1
2.05
2
1.95
1.9
1.85
1.8
1.75
1.6
1.65
1.7
1.75
1.8
1.85
logC-seglengthAV
Y = -.257 + 1.266 * X; R^2 = .75
Mid Term Event
i-VALUL the intangible value of urban layout
1.9
1.95
2
Centre
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
Choice 800m
i-VALUL
iValul
Univariate Line Chart
6000
What do we find?
5000
1. Centres have shorter segment lengths
Centre
Variables
4000
2. In all cases, centres have higher local choice3000
2000
Non-Centre
1000
2.
0
Observations
segL
max
segL
av
ch300
Ch 400
Ch 800
Ch 2000
Ch10,000
n
Centres
155.9
56.9
156.2
356.7
5632.4
9,3441
31,107,168
2,502,094,571
Noncentres
248.7
93.7
90.6
212.0
4,366.9
8,3634
32522119
2,502,215,728
%
difference
-39%
-39%
+72%
+68%
+29%
+12%
-4.5%
0.0%
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
Choice 10,000m
i-VALUL
iValul
6E9
What do we find?
5E9
1. Centres have shorter segment lengths
2. Centres have higher local choice
3. But the difference disappears as we
increase the radius from local to global)
Variables
4E9
Centre
3E9
2E9
1E9
0
Non-Centre
-1E9
Observations
segL
max
segL
av
ch300
Ch 400
Ch 800
Ch 2000
Ch10,000
n
Centres
155.9
56.9
156.2
356.7
5632.4
9,3441
31,107,168
2,502,094,571
Noncentres
248.7
93.7
90.6
212.0
4,366.9
8,3634
32522119
2,502,215,728
%
difference
-39%
-39%
+72%
+68%
+29%
+12%
-4.5%
0.0%
Mid Term Event
i-VALUL the intangible value of urban layout
3.
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Choice R400
Choice R800
Choice R2000
700
600
500
Centre
Centre
Non-Centre
Non-Centre
Centre
400
300
200
100
Non-Centr
0
Choice R10000
Choice RN
Centre
Centre
Non-Centre
Non-Centre
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
4.00
Centre Groups
Centre – Non-centre
variable for the
10 high streets at
different radii.
(Average Centre /
Average non-centre)
3.00
2.00
Chisw ick av
Kilburn av
Sw iss Cottage av
West Ealing av
Mid Term Event
i-VALUL the intangible value of urban layout
Clapham av
North Finchley av
Tooting av
CH_RN
CH_R10000
CH_R7500
CH_R5000
CH_R4000
CH_R3000
CH_R2000
CH_R1200
CH_R800
CH_R600
CH_R400
0.00
CH_R300
1.00
Hampstead av
Streatham av
Walw orth Road av
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
4.00
Group 1
3.00
2.00
Clapham av
Mid Term Event
i-VALUL the intangible value of urban layout
Hampstead av
Tooting av
CH_RN
CH_R10000
CH_R7500
CH_R5000
CH_R4000
CH_R3000
CH_R2000
CH_R1200
CH_R800
CH_R600
CH_R400
0.00
CH_R300
1.00
The centre segments
have a slightly higher
choice values (10-40%)
than the non-centre
segments from a radius
of 400 to 3000m. They
peak at 800m
(Hampstead) and 1200
m (Clapham, Tooting),
but this is not
significantly higher than
the other values. From
a radius of 3000, only
Hampstead and Tooting
show higher values in
the centre, while
Clapham has higher
non-centre values.)
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Group 2
4.00
These centres have a
small peak at local
radius of 400m, stay
significantly higher
up to 1200m and
decrease to similar
values as the noncentre segments.
(Streatham,
Walworth Rd)
3.00
2.00
Streatham av
Mid Term Event
i-VALUL the intangible value of urban layout
CH_RN
CH_R10000
CH_R7500
CH_R5000
CH_R4000
CH_R3000
CH_R2000
CH_R1200
CH_R800
CH_R600
CH_R400
0.00
CH_R300
1.00
Walw orth Road av
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
4.00
Group 3
These centres show a
high peak (over 2) at a
radius between 400m
(Clapham, West Ealing),
600m (Swiss Cottage)
and 800m (Kilburn) and
decrease than to a level
of 0.7 to 1.5 at higher
radii.
3.00
2.00
Kilburn av
North Finchley av
Mid Term Event
i-VALUL the intangible value of urban layout
Sw iss Cottage av
CH_RN
CH_R10000
CH_R7500
CH_R5000
CH_R4000
CH_R3000
CH_R2000
CH_R1200
CH_R800
CH_R600
CH_R400
0.00
CH_R300
1.00
West Ealing av
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
Integration R400
Integration R800
Integration R2000
Centre
Non-Centre
Non-Centre
Centre
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
B. Centre – context
The relationship between local and global measures is crucial.
Different centres behave differently.
Let’s look at the differences between centres and
their context – our second key variable along with
centre - non-centre.
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
C. Centre – context
How do centres
stand out from their
context?
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
We already know that centres vary on different radii:
B. Centre – context
Global movement
Choice R400
Choice RN
Up
pe
r
Up
pe
r
To
oti
To
oti
ng
Ro
ad
ng
Ro
ad
Local movement
m
ha
itc
m
ha
itc
M
M
Rd
Rd
Tooting
Mid Term Event
i-VALUL the intangible value of urban layout
Tooting
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
But can we measure how centres stand out from their
context?
C. Centre – context
We do this by calculating the ratio between the spatial
values of the segments in the centre and their context in
different radii.
In all cases the centre segments are sharply
distinguished from their surrounding context.
The difference increases with increasing radius
Descriptive Statistics
Mean
Std. Dev.
Std. Error
Count
Minimum
Maximum
# Missing
CC/ped800segA400avg
2.397
.609
.193
10
1.643
3.339
0
CC/ped800segA800avg
3.230
.696
.220
10
2.539
4.543
0
CC/ped800segA2000avg
4.356
.903
.286
10
3.019
5.584
0
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
How do centres stand out from their context?
C. Centre – context
Centre - Context CHOICE R2000
6
5
4
3
2
Mid Term Event
i-VALUL the intangible value of urban layout
Hampstead
Swiss Cottage
North Finchley
Clapham
Chiswick
West Ealing
Kilburn
Streatham
Tooting
0
Walworth Road
1
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
How do centres stand out from their context?
C. Centre – context
Regression Plot
Centre-context ratio
strongly correlates
with pedestrian
activity.
15000
14000
R15_pedactivity
13000
12000
The higher the ratio
the higher the level of
pedestrian activity
11000
10000
9000
8000
7000
6000
2.5
3
3.5
4
4.5
5
CC/ped800segA2000avg
Y = 1767.536 + 2016.606 * X; R^2 = .584
Mid Term Event
i-VALUL the intangible value of urban layout
5.5
6
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
How do centres stand out from their context?
C. Centre – context
Regression Plot
SE27_averagelocalexpenditure
240
Centre-context ratio
correlates negatively
with average local
expenditure
220
200
180
160
140
120
100
80
2.5
3
3.5
4
4.5
5
CC/ped800segA2000avg
Y = 295.955 - 33.851 * X; R^2 = .586
Mid Term Event
i-VALUL the intangible value of urban layout
5.5
6
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
How do centres stand out from their context?
C. Centre – context
Regression Plot
70000
Centre-context ratio
correlates with
higher local
population and
employment
densities
65000
totalPOP+EMP
60000
55000
50000
45000
40000
35000
30000
25000
2.5
3
3.5
4
4.5
5
CC/ped800segA2000avg
Y = 9755.183 + 8954.775 * X; R^2 = .452
Mid Term Event
i-VALUL the intangible value of urban layout
5.5
6
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
How do centres stand out from their context?
C. Centre – context
Regression Plot
1200
that it correlates
weakly but
negatively with Zone
A rental values, with
the highest values
associated with the
centre most
integrated into its
contextual area.
R12_rentperzoneAsqm
1100
1000
900
800
700
600
500
400
300
200
2.5
3
3.5
4
4.5
5
CC/ped800segA2000avg
Y = 1247.326 - 170.07 * X; R^2 = .354
Mid Term Event
i-VALUL the intangible value of urban layout
5.5
6
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
Results
i-VALUL
iValul
There is a generic economic value associated with the variables which
distinguish a centre from its context, since these create the conditions for a
successful centre in the first place.
This however is realised in two different ways:
1. Popular centre
- the centre is sharply distinguished from its context on choice
- which has high local population and employment densities
- has high rates of pedestrian activity
- success comes from numbers rather than affluence
- larger, less street oriented shops
2. Selective centre
- the centre is more part of its context on choice
- has lower local population and employment densities
- lower rates of pedestrian activity
- success comes more from high value and local affluence
- smaller, more street oriented shops
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Integration
Integration R400
100
Hampstead
C- K400_MD400_AV
95
90
85
Tooting
Sw iss Cottage
Walw orth Road
North Finchley
80
75
70
65
60
the key selectives
are the best
integrated into their
neighbourhoods at
400m
but the top
populars are also
almost as good
Streatham
West Ealing
Chisw ick
Kilburn
55
Clapham
50
centre-context order
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Integration R800
Integration
240
Sw iss Cottage
C-K800_MD800_AV
230
220 Tooting
210
Walw orth Road
and at 800 they are
more similar
North Finchley
200
190
Hampstead
Streatham
180
170
160
Kilburn
Chisw ick
150
140
130
West Ealing
Clapham
centre-context order
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
The starting point…
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
High street vitality
Street
design
Street
layout
CABE (2007)
Paved with
Gold
i-VALUL (2008)
Formed of
Gold?
Vitality ££
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
The Paved with Gold model
Average zone A rent (£/m2)
=
constant
+
a*Vacant units variable
+
b*Local spending power
+
c*Competition factor
+
d* Street design quality var
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
A similar approach…
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
1400
1200
observed
Average retail
zone A rent per
sqm (£)
Average zone A rent (£/m2) =
regression
constant
+
1000
800
a* Local spending power
+
600
b* Competition factor
+
400
200
Mid Term Event
i-VALUL the intangible value of urban layout
West Ealing
Walworth Road
Tooting
Swiss Cottage
Streatham
North Finchley
Kilburn
Hampstead
Clapham
Chiswick
0
c* Local accessibility variable
(Average Choice 800m)
+
d* Street design quality variable
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
But…
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
Street design quality can thought of as linear…
… so improved access, attractiveness and
performance are assumed to translate into ££’s
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
As seen in Prof Bill Hillier’s presentation
• Centres are spatially distinguishable from non-centres
• The formation of centres can be thought of as a process
leading to different centres types
(Popular centres, selective centres)
• One main factor is the relationship centre – context
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
An alternative approach…
…Can we explain total rateable
value?
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
Correlation between
Centre - Context
variable and
floorspace
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
6.000
CCped800segA2000avg
5.500
Tooting
Walworth Road
Streatham
Kilburn
5.000
West Ealing
4.500
4.000
Chiswick
Clapham
3.500
North Finchley
Swiss Cottage
R Sq Linear = 0.196
Zone A floor space as
a percentage of total
floor space can be
used an indicator of
the extent to which a
high street relies on
frontage-focussed
retail.
Sites with a lower
centre context
indicator tend to have
a more
frontage-focussed
retail offer.
Hampstead
3.000
0.10
0.125
0.15
0.175
0.20
0.225
R8g_zoneAareatotalarea
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
Typology
Hampstead and North
Finchley: well embedded
and high core
penetration
6.000
CCped800segA2000avg
5.500
Tooting
Walworth Road
Clapham, Swiss
Cottage, Chiswick:
fairly well embedded and
low core penetration
Streatham
5.000
Kilburn
West Ealing
4.500
4.000
Chiswick
Clapham
North Finchley
3.500
Swiss Cottage
Hampstead
Walworth, Kilburn,
Streatham: nonembedded and low
core penetration
3.000
0.00
0.01
0.02
0.03
0.04
R17_corepenetration
Mid Term Event
i-VALUL the intangible value of urban layout
0.05
0.06
0.07
Tooting, West Ealing:
non-embedded and high
core penetration
UrbanBuzz
© Space Syntax 2008
UrbanBuzz
4.1 Knowledge Integration KIT3 - Centres
Building sustainable communities
i-VALUL
iValul
12,000,000
observed
Total retail
zone A rent (£)
10,000,000
regression
Total rateable value (£)
=
constant
8,000,000
+
6,000,000
a* Total floorspace
+
4,000,000
b* Average local spending power
+
2,000,000
Mid Term Event
i-VALUL the intangible value of urban layout
West Ealing
Walworth Road
Tooting
Swiss Cottage
Streatham
North Finchley
Kilburn
Hampstead
Clapham
Chiswick
0
c* Local accessibility variable
(Average Choice 800m)
d* Centre context dummy
(Centre/Context > 4.5 = 1)
UrbanBuzz
© Space Syntax 2008
4.1 Knowledge Integration KIT3 - Centres
UrbanBuzz
Building sustainable communities
i-VALUL
iValul
Some conclusions
• Evidence that the spatial accessibility of the centre especially
at a local radius up to 2 km is important for its performance
• Evidence that the street layout of the context is important for
high street performance
• Differentiation of centre types according to centre-context
relationship
• Promising approach for evaluating alternative floorspace
scenarios
Mid Term Event
i-VALUL the intangible value of urban layout
UrbanBuzz
© Space Syntax 2008