Rosslyn Sector Plan County Board Work Session July 7, 2015 Outline of Presentation
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Rosslyn Sector Plan County Board Work Session July 7, 2015 Outline of Presentation 1. Introduction - background 2. Methodology and Public Process (establishment of the view corridors building of the model, the criteria/goals, process panel/subcommittee review) 3. Fly through and fixed views from Observation Deck (including descriptions of the landmarks visible as outlined in the draft plan) 4. Opportunity to navigate model 2 1. INTRODUCTION Project Scope Elements related to Building Height In 2011, the County Board approved a scope of work for the study to address these issues related to Building Height: . Whether, and under what circumstances should new buildings be allowed to pierce the current 300 feet maximum in certain places (outside of Central Place)? . What are the recommended maximum building heights for individual blocks in Rosslyn? . What policies can be established to balance the sometimes competing interests of view corridors, skyline composition, etc.? . How can building height help contribute to better conditions on the ground-plane? . What is the proper balance between prescription and flexibility with regards to all building height issues? . What strategies can be used to help achieve appropriate transitions between the core of Rosslyn and its edges? 1. INTRODUCTION Existing Planning and Zoning for Height in Rosslyn Heading into this study, the planning policies and zoning regulations that currently influence building height in Rosslyn include: . “C-O Rosslyn” Zoning District provisions . 2002 County Board Resolution on Building Height in Rosslyn . 2007 County Board Resolution on Central Place . Central Place Site Plan 335 and its Public Observation Deck 1. INTRODUCTION “C-O Rosslyn” Zoning District . “C-O Rosslyn” District: Development Parameters (established 1996) . By-Right Projects Maximum Height: 35 feet . Special Exception Site Plan (standard site plan) Maximum Height: 153 feet (office), 180 feet (residential or hotel) . Special Exception Site Plan (provisions for additional height) Maximum Height: up to 300 feet (or up to 400+/- feet in Central Place) 1. INTRODUCTION 2002 Resolution 2002 Resolution Governing Building Heights in Rosslyn . Further articulates goals of General Land Use Plan and 1992 Rosslyn Station Area Plan Addendum – Greatest building heights closest to Metro – Tapering of building heights further away from Metro – Consider impact on “view corridors” – Design of building tops should consider impact on skyline 1. INTRODUCTION 2007 Resolution 2007 Resolution on Urban Design Principles for Rosslyn Central Place (Prompted by review of development proposals for two Central Place blocks, and associated zoning ordinance amendment) . Views from any public observation deck within Central Place should be preserved . Calls for sculpted rooftop designs and significant tapering in height and form . Reinforced incorporation of significant community benefits with additional density and height 1. INTRODUCTION ProjectCentral Schedule Place – Site Plan 335 Site Plan Amendment approved in May 2007 PROJECT HIGHLIGHTS . 377 Residential Units Office . 570,000 square feet of Office GFA . 44,500 square feet Retail GFA . Mid-block Public Plaza . Public Observation Deck 8 1. INTRODUCTION ProjectCentral Schedule Place – Site Plan 335 Public observation deck included as $14 million community benefit = 360 degree public view opportunities (to be reflected in corrected inset maps in sector plan) 9 1. INTRODUCTION ProjectSummary Schedule of Introductory Points . When “C-O Rosslyn” first established, no clear guidance for where in the RCRD the 300’ building height would be appropriate . 2002 Resolution introduced the “Taper Policy”, with tallest buildings at Metro and heights tapering down further from Metro . 2007 Resolution made note of importance of protecting views from any observation deck within Central Place . In 2007, County Board approved Central Place site plan, which included public observation deck as major community benefit . Taper policy has yet to be tested at the edge sites . With these actions, more clear guidance is needed on how much building height is appropriate for different areas of the RCRD 10 2. METHODS AND PROCESS ProjectMethodology Schedule and Public Process . Process Panel / Subcommittee review . Planning goals / Evaluation Criteria . Establishment of the view corridors and other Framework guidance . Building of the 3D computer model (including assumptions) . Preliminary modeling demonstrates constraints of Taper Policy . More refined modeling of proposed Peaks and Valleys policy 11 2. METHODS AND PROCESS Project SchedulePublic Process 2013 . Initial round of modeling and public meetings April 2014 . Framework adopted Summer/Fall 2014 . 5 subcommittee meetings to review additional modeling March 2015 . Count Board work session Ongoing meetings with stakeholders 12 2. METHODS AND PROCESS ProjectRosslyn Schedule Plan Framework Policy Directive: Develop a new building heights policy and regulatory framework for Central Rosslyn that incorporates varied building heights across the district and advances the following principles more effectively than the current general taper policy: . Sensitive edge transitions . Observation deck view corridors . Ground level view corridors . Sun/shade . Great public open spaces . Marketable buildings 13 2. METHODS AND PROCESS PrioritizingProject ScheduleObservation Deck View Corridors Board content from October 2013 workshop 2. METHODS AND PROCESS ObservationProject Deck Schedule View Corridors and Edge Transitions 2. METHODS AND PROCESS Project ScheduleBlock Structure 16 2. METHODS AND PROCESS Project Schedule Building the 3D Computer Model (Assumptions) Overview . Framework Plan . Policy directives . View corridors and edge transitions . Street and open space network . Potential densities based on full site area (land parcels) . Work with best available information on airspace/FAA . Model building shapes and sizes that can work for the market . Assume below-grade parking, in estimating density yields . Target an FAR minimum of 8.0, ideally between 9.0 and 10.0 FAR 17 2. METHODS AND PROCESS BuildingProject the ModelSchedule – SketchUp and County Data . County GIS . Planimetric data . Topographic data . Parcel data . Sketchup 3D modeling . Existing/approved sites Existing buildings likely to redevelop Existing buildings likely to remain Approved buildings 18 2. METHODS AND PROCESS Building theProject Model Schedule – Densities based on full site area • Key Point: Lower height does not necessarily mean lower density Maximum Ground floor footprint Site area per land parcel(s) 1901 N. Moore St. 1400 Wilson Blvd. Ground floor: Site area = 100% Ground floor: Site area = 61% Modeled FAR: 10± Modeled FAR: 9.0± Height: 260’ Height: 260’ 19 2. METHODS AND PROCESS BuildingProject the Model Schedule – Airspace/FAA Considerations ASSUMPTION: . Explore potential heights in the RCRD up to a maximum of 470’ above sea level (asl) – Same elevation as tops of Central Place Office and 1812 N Moore – Understood as upper building limits relating to FAA and TERPS – No known precedent of FAA “approving” any building above 470’ ASL in RCRD – FAA consideration of including OEI into standard reviews is pending 20 2. METHODS AND PROCESS BuildingProject the Schedule Model – Marketable Buildings ASSUMPTION: . Floorplates that work for their intended uses – Office: 20,000sf-30,000sf 100-120’ wide, (deeper w/ atrium); 13’ high floors – Housing/hotel: 8,000sf min.10,000sf+ preferred 60’ -70’ deep (up to 100-110’ possible) 10’-11’ high floors . Maximize opportunity for views out . Separate towers at least 60’ . Incorporate diverse use and form . Multiple program options 21 2. METHODS AND PROCESS ProjectBuilding Schedule the Model – Parking ASSUMPTION: . County generally promotes below-grade parking near Metro . Bedrock conditions in eastern Rosslyn have resulted in some above grade parking in some instances . Studies and models assumed all parking provided below grade, to estimate density yields consistently 22 2. METHODS AND PROCESS BuildingProject the Model Schedule – Target density at/near 10 FAR ASSUMPTION: . Densities generally approaching 9-10 FAR may be most effective in incentivizing redevelopment . Exact FAR needed to build a “C-O Rosslyn” site plan will depend on a number of factors 23 2. METHODS AND PROCESS ProjectFindings: Schedule Drawbacks of Taper Policy . As modeled, average FAR of future development sites is approximately 7.5 FAR . Constrains FAR at edge sites, limiting project feasibility . Could yield broad, boxy buildings One Example of the Modeled Taper Policy . Less opportunities for open space and space between towers 2. METHODS AND PROCESS ProjectFindings: Schedule Drawbacks of Taper Policy Wilson Blvd. sections looking north Minimizing height to achieve real taper (with Rosslyn’s slope) may reduce density to Scenario: height a point of stalling or tapered; FAR reduced to fit precluding redevelopment Maximizing development potential while applying current taper policy would yield broad, boxy buildings – Scenario: height minimized; FAR in some cases with maximized (FAR 10) unmarketable floor plates A Peaks and Valleys alternative with varied height could optimize overall Scenario: height varies performance of building form higher/lower; FAR maximized (FAR 8-10) 25 2525 2. METHODS AND PROCESS How areProject “Peak” Schedule and “Valley” areas determined PEAKS, general influences . Areas outside of priority obs. deck view corridors . Areas away from edge transitions