Realizing Rosslyn: a new era of opportunity
PRESENTATION OUTLINE 2
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Building tops tour: what we observed 5
Building height/form and urban design: interrelated elements 6
WORK SEQUENCE 7
Building height/form and urban design can make or break progress toward all the vision principles 8
What we heard at the workshops: views 9
What we heard at the workshops: height/form 10
What we heard at the workshops: street network 11
What we heard at the workshops: street activity 12
Draft framework: what we heard from you 13
Draft framework: what we heard from you 14
Translating vision principles into urban design qualities 15
Competitive: buildings that create value 16
Good neighbor: sensitive transitions 17
Accessible: leveraging transit, walking, biking 18
Walkable: safe, welcoming walking routes 19
Connected to nature: permeated by green systems 20
Dynamic: inviting 24/7 activity, diversity 2010 Base Plus Turnberry Tower 5% 1% 7% 6% 81% 7% 4% 1% 2040 current forecast New: 22% housing, 68% office 11% 77% Office Retail Other Hotel Residential 2040 potential target? New: 36% housing, 54% office 1% 4% 7% 18% 70% 21
ANALYSIS ASSUMPTIONS/POLICY CONTEXT 22
Building Form and Height Analyses: Starting Points 23
Building Form and Height Analyses: Starting Points 24
Building Form and Height Analyses: Starting Points 25
Building Form and Height Analyses: Starting Points 26
C-O Rosslyn Summary Points 27
Community Benefits: Examples from approved site plans Central Place (2007) 1812 North Moore (2007) Rosslyn Gateway (2012) Benefits beyond standard site plan conditions 28
Overall Approach to Modeling of Scenarios 29
Block pattern & redevelopment site assumptions 70 N/A 30
Intensity translates differently on each site 31
Street width assumptions 32
How does this affect public deck view corridors? 33
here does height fit best? 34
Building form analysis performance criteria 35
General Transition variations Core Building form analysis scenarios Approach G1. Existing policy/taper from Metro FAR varies: Distinct taper effect imposed regardless of site elevation or development potential. Less than 10 FAR applied to some sites to preserve taper, views, passages G2. Existing policy/taper from Metro FAR 10: Building heights greatest at Central Place, taper down to all edges as possible T1. 1:1 Taper: Taper up to 300 feet @ 1:1 from building heights adjacent to RCRD T2. Enhanced taper: Long, stepped forms facing context, with courtyards/atriums T3. Open space transition: Terraced open space between context/new devt. T4. Peaks and valleys: Slender, tall forms facing context, spaced out C1. Framed public views: Priority public deck views preserved; taller buildings rise between views (reflected in certain Transition variations) Effects Public deck views and ground level open space increased, but development value constrained. Consider transfer of development rights (TDR) if height/form diversity can be maintained (unlike recent projects with more uniform height) Heights minimized, maximizing observation deck views, but building widths maximized, posing scale, connectivity and marketability challenges Effective scale transitions, but building widths pose view/scale/market challenges unless heights can impede certain public deck view directions More sun/sky access, but increased height along context Public and/or private open space increased, but scale transitions abrupt More sun/sky access, but increased height along context Core sites retain full development capacity, add skyline variation, and create ground level open space, but public deck views constrained. Peaks can heighten as valleys deepen at neighborhood and park edges 36
Existing conditions from high above 37
Existing conditions Bird s eye view 38
Existing conditions section view 39
General scenarios: G1. Existing policy/taper from Metro, FAR varies 40
General scenarios: G1. Existing policy/taper from Metro, FAR varies 41
General scenarios: G1. Existing policy/taper from Metro, FAR varies 42
General scenarios: G2. Existing policy/taper from Metro FAR 10 43
General scenarios: G2. Existing policy/taper from Metro FAR 10 44
General scenarios: G2. Existing policy/taper from Metro FAR 10 45
General scenarios: G2. Existing policy/taper from Metro FAR 10 46
General scenarios: G2. Existing policy/taper from Metro FAR 10 47
Taper scenario challenges 48
Transition scenarios: T1. 1:1 Taper 49
Transition scenarios: T1. 1:1 Taper 50
Transition scenarios: T1. 1:1 Taper 51
Transition scenarios: T2. Enhanced taper 52
Transition scenarios: T2. Enhanced taper 53
Transition scenarios: T2. Enhanced taper 54
Transition scenarios: T3. Open space transition 55
Transition scenarios: T3. Open space transition 56
Transition scenarios: T3. Open space transition 57
Transition scenarios: T4. Peaks and valleys 58
Transition scenarios: T4. Peaks and valleys 59
Transition scenarios: T4. Peaks and valleys 60
Transition scenario trade-offs: Lower height means greater width 61
Transition scenario trade-offs: Tapering improves scale transitions 62
Transition scenario trade-offs: Greater height could bring more sky, sun, variety 63
Transition scenario trade-offs: Adding park transition increases height contrast 64
Transition scenario trade-offs: and can obstruct deck view corridors 65
Transition scenario trade-offs: Shifting height to view shadows could help 66
Core scenario trade-offs: Shifting height to view shadows could help 67
Core scenario trade-offs: Heights, view corridors, open space and variety 68
Core scenario trade-offs: Heights, view corridors, open space and variety 69
Core scenario trade-offs: Heights, view corridors, open space and variety 70
Core scenario trade-offs: Heights, view corridors, open space and variety 71
The skyline from afar: Limiting height and width diversity limits identity 72
The skyline from afar: Limiting height and width diversity limits identity 73
The skyline from afar: Rosslyn Plaza important to form variety 74
The skyline from afar: Wilson corridor height/form options are limited 75
Discussion questions 76