d esign review - denver · 2015-06-22 · sky exposure diagrams, shadow study (if shadow falls on...

D E S I G N R E V I E Wf o r B 5 D O W N T O W N Z O N I N G

D E S I G N R E V I E Wf o r B 5 D O W N T O W N Z O N I N G

S T A N D A R D S , G U I D E L I N E S A N D P R O C E S SC O M M U N I T Y P L A N N I N G A N D D E V E L O P M E N T A G E N C Y

C I T Y a n d C O U N T Y o f D E N V E R

S P R I N G 1 9 9 5C I T Y a n d C O U N T Y o f D E N V E R

S P R I N G 1 9 9 5

S T A N D A R D S , G U I D E L I N E S A N D P R O C E S SC O M M U N I T Y P L A N N I N G A N D D E V E L O P M E N T A G E N C Y

COLFAX

CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Objectives

Organization

Process

Procedures For Design Review. . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Participants

Review Process Options

Required Submissions

Appeal Options

Design Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Design Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

D E S I G N S TA N D A R D S

1

Introduction

■ Objectives

These Design Review Standards andGuidelines have been created through thejoint efforts of downtown business andprofessional organizations and theDenver Planning and DevelopmentOffice with the understanding thatDowntown is and must remain our finestand most prominent public environment.The Standards and Guidelines containedherein address the quality of that publicenvironment, recognizing that it isultimately formed by a thousandindividual, private creative decisions. It isthe intent of these documents to providedirection to those decisions in thecommon interest of creating an urbancenter that is at once comfortable,delightful, exciting and without questionthe business and entertainment center ofthe region.

■ Organization

There are three primary sections to thisdocument, Procedures for Design Review,Design Standards and Design Guidelines.The review procedures are intended to beclear, precise and flexible, allowing a choiceof review sequences to be based ondevelopment schedules and designintentions. The review and submittalrequirements closely parallel others in theDenver area that are familiar to developers.The applicant or designer using thisdocument should be familiar with theprocedures for design review beforereferring to the standards or guidelinessections. Project design intentions andschedules may need to be considered priorto determining which review process willbest suit the project needs.

■ Process

Design review is mandatory for allprojects meeting the criteria specified inSection 59-368 of the zoning code.However, there are two primary reviewprocesses to choose from; the fast andobjective Design Standards (“theCookbook”) or the more deliberative andflexible Design Guidelines.

The “Cookbook” Design Standardsreceived their nickname from theirintention of creating a clear andunequivocal “by the book” approach todesign review. Within the “Cookbook”some very basic concepts about whatmakes the architecture of downtownDenver streets unique, comfortable andattractive have been prescribed in anobjective and quantifiable manner. Thesestandards address issues of pedestrianamenities such as scale, access, pedestrianoriented activity, and environmentalcomfort.

The Design Guidelines recognize that notevery project wants to be or should be“by the book”. There are many more waysof achieving excellence than can possiblybe anticipated when drafting standards.These guidelines describe the goals ofdesign in Downtown Denver: toencourage variety, creativity and qualityin architectural design, to promote wellproportioned and active streets, toenhance human scale, amenity andenvironmental comfort, and to respectthe historic heritage of our uniquelocation. They invite new projects torecognize these goals and to work withthe City to achieve the highest return tothe community.

B 5 D E S I G N R E V I E W

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Procedures for

Design Review

Design Standards and Guidelines areauthorized by the Zoning Ordinance ofthe City and County of Denver and are tobe used in conjunction with thatordinance as it applies to the DowntownB5 Zone District.

■ I. Participants

Design review will be conducted by the Deputy Director of Planning forUrban Design and other designated staff as appropriate. Participants from the development team shall include arepresentative of the applicant (owner, developer), the architect andother development team members as appropriate.

■ II. Review Process Options

All applicants have two design reviewoptions and may select the process thatbest suits the needs of their project. Toprovide maximum flexibility differentcomponents or different phases of anindividual project may go throughdifferent design review processes and maydo so simultaneously. The design reviewprocess selected may have design andschedule implications, therefore athorough understanding of the reviewoptions is important at the outset of designand project scheduling. The developmentteam should make the Deputy Director forUrban Design aware of the preferreddesign review option and project scheduleat the earliest possible date to facilitateexpeditious review. The review processselection may be changed at the applicant’soption as project development warrants.

Option One — Design StandardsReview • “The Cookbook”

Design Standards Review is based on theDesign Standards contained in SectionThree of this document. This is the fastestand most objective review process. Allaspects of a project that meet the DesignStandards will be approved through areview to be completed in no more than15 calender days.

Option Two — Design GuidelinesReview

Design Guidelines Review is based on theDesign Guidelines contained in SectionFour of this document. These guidelinesparallel the Design Standards in SectionThree but allow for broader interpretationof the goals of those standards. Any aspect

D E S I G N R E V I E W ◗ P R O C E D U R E S

3

of project design that does not literallyconform to the Design Standards may besubmitted for review under the guidelinesindependent of other design issues. DesignGuidelines Review is conducted throughnegotiation with the Deputy Director ofPlanning for Urban Design and designatedstaff to be completed in no more than 45calender days.

■ III. Review Schedule and

Submission Requirements

Design review under either option may berequested by the applicant at any point inthe development process as may berequired to provide clear direction onspecific issues. The Planning Office requiresmeetings with the development team andsubmittal of design documents at thefollowing key project phases: Pre-DesignConference, Concept and/or SchematicDesign, Design Development andpermitting. The Applicant must submitdesign documents appropriate to the phaseand level of project development at thetime review is requested. Sufficientinformation and detail must be providedto fully evaluate relevant issues at eachphase. Some or all of the followinginformation will be required, as applicable,prior to completion of all design reviewphases but may not be required at eachseparate phase:

◗ Declaration of intent to be reviewedunder the Design Standards or theDesign Guidelines.

◗ Request for special considerations ie.,phasing, etc.

◗ Project program indicating buildingareas and uses.

◗ Design documents to include:

◗ Site and Context Plan

◗ Building and Context Elevations

◗ Detailed Ground Floor Plan

◗ Building and Context Sections

◗ Architectural facade details (lowereighty feet)

◗ Building Materials Schedule (samplesif requested)

At the completion of review of eachsubmittal the applicant will receive adetermination of consistency or approvalto proceed with noted conditions.Consistency determinations and approvalsat each phase will be valid for a period ofthree years, unless extended by thePlanning Office in accordance withprovisions of the B-5 Zone DistrictOrdinance. All conditions must be resolvedprior to permit submittal and adetermination of consistency with allreview requirements must be issued priorto permitting.

Note: The review process may be delayedby the incomplete submittal of requiredreview documentation. Review may also bedelayed at the request of the developer. Thefollowing items are required to meetspecific standards set by ordinance and notsubject to design guideline interpretation:Sky exposure diagrams, Shadow study (ifshadow falls on 16th Street Mall)

■ IV. Appeal Options

If a design is not approved under DesignStandards Review the applicant may: reviseand resubmit, opt for Design GuidelinesReview or appeal to the Downtown DesignReview Appeals Committee.

If a design is not approved under DesignGuidelines Review the applicant may:revise and resubmit or appeal to theDowntown Design Review AppealsCommittee as provided for by ordinance.


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DESIGN STANDARDS

“THE COOKBOOK”

D E S I G N S TA N D A R D S ◗ T H E C O O K B O O K

5

Section 1:

Fenestration

Wall to Window Ratios

(Solid to Transparent)

Intent: 1) Require moretransparent and open lowerfloor facades, in order toinsure the visibility ofpedestrian active uses, andprovide a lighter, moredetailed and human scaledarchitectural expression alongthe sidewalk and,

2) Require a more solid wallwith a pattern of individualwindows at the upper floorsin order to provide greatervariety of scale throughfenestration patterns,architectural elements, surfacerelief, texture and materials.

Transparency and

Reflectivity

Intent: 1) Insure thevisibility of pedestrian-activeuses; 2) to reduce theamount of glare produced byhighly reflective glass.

◗ Section 1.1: Between 60%and 90% of the groundfloor facade (as measuredfrom floor to floor), andany second floor facadecontainingpedestrian-active uses, shallbe made of transparentmaterials, or otherwisedesigned to allowpedestrians to viewactivities inside thebuilding or displays relatedto these activities.(Illustration 1)

Transparent glass shallpossess a minimum 60%light transmittance factor.

Parking garages areexcepted from the groundfloor and second floortransparency standard ifthey do not provide groundfloor pedestrian active uses.

◗ Section 1.1a: No portionof the facade shall be ofhighly reflective glass(maximum reflectancefactor of: .25). Noreflective coating shall beon the first (exterior)surface of the glass.

◗ Section 1.2: Between 25%and 40% of the facade areafor each building facadedirectly adjoining a street,excepting parking garages,shall be made oftransparent materials.(Minimum lighttransmittance factor shallnot be applied abovesecond floor)

◗ Section 1.2a: No portionof the facade shall be ofhighly reflective glass(maximum reflectancefactor of: .25). Noreflective coating shall beon the first (exterior)surface of the glass.

◗ Section 1.2b: Upperfloors may utilize opaqueglass to meet minimumglazing requirementswhere it is determined forreasons of use orconstruction thattransparent glazing is notfunctionally feasible.Opaque glazing may notexceed 15% of the facadearea for each buildingfacade directly adjoininga street.

◗ Section 1.3: ParkingGarages: Parking garageopenings which face anystreet shall be horizontallyand vertically aligned.(Illustration 2) Parkinggarage facades shallconceal from view theentirety of all parkedvehicles from the far sideof any street R.O.W. that iscontiguous to the propertywithin which the garage islocated.

◗ Section 1.3a: OtherBuilding Types: Thoseportions of any facility thatare functionally required torestrict natural daylight orviews into the facility maybe exempted from the 25%minimum transparentmaterials requirement solong as any resulting blankwalls adjoining a street orpublic space providearchitectural scalingelements as describedunder Section 3.

◗ Section 1.3b: ExistingBuildings: Glazingrequirements do not applywhen restoring originalfeatures of existingbuildings.

BUILDING

ELEMENTS

TYPICAL REQUIREMENTS

GROUND FLOOR TO SECOND FLOOR


THIRD FLOOR TO 80 FEET

SPECIAL REQUIREMENTS

OR UNIQUE CONDITIONS

◗ ◗ ◗ ◗


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D E S I G N S TA N D A R D S ◗ T H E C O O K B O O K

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3RD FLOOR AND ABOVE: 25% TO 40%WINDOW TO WALL RATIO

2ND FLOOR: 40% TO 90% WINDOW TO WALL RATIO

1ST FLOOR: 60% TO 90% WINDOW TO WALL RATIO

ILLUSTRATION 1 — WINDOW TO WALL RATIOS

ALIGN OPENINGS VERTICALLY &HORIZONTALLY - NO EXPOSED RAMPS

CONCEAL PARKED CARS FROM VIEWFROM ADJOINING PUBLIC SPACE

ILLUSTRATION 2 — PARKING GARAGE SCREENING

RIGHT-OF-WAY

ILLUSTRATIONS AND NOTES

Section 2: Building

Placement & Access

Build-To Lines and Zones

Intent: Define and containthe street space in order toconcentrate and reinforcepedestrian activity and tocreate a sense of the street asa “place” in the city.

Entries

Intent: Reinforce theconvenience of pedestrianactivity and circulation alongthe street by creating as manyexternal, street orientedentries as possible to groundfloor “pedestrian active” uses.

◗ Section 2.1: From the SWside of 14th St. to the NWside of 18th St., and fromBroadway and Colfax tothe Larimer/ Market Streetalley, buildings shall bebuilt-to or within 10 feet ofthe property line adjoiningthe street for no less than65% of each separatelyowned zone lot frontage;except along the SW side ofthe 16th St. Mall where thebuild-to zone will beincreased to 20 feet. (seealso Section 2.3d)

In the B5 district northeastand southwest of the abovenoted area, buildings shallbe built to or within 10' ofthe property line adjoiningthe street for no less than50% of each separatelyowned zone lot frontage.(Illustrations 3A& 3B)

◗ Section 2.1a: Wherepedestrian active uses facethe 16th St. Mall, thereshall be at least one entry1) every 50 linear feetalong the Mall, or 2) foreach tenant adjoining theMall, giving public accessto such uses.

◗ Section 2.2: Theminimum height ofbuilding frontage requiredto be constructed within orup to the build-to zone isthirty feet (30').

◗ Section 2.2a: Within 50feet of the 16th Street Mallno building or portion ofbuilding shall exceed 200feet in height. Buildingslocated entirely on zonelots of 15,000 square feetor less shall be exemptfrom this provision.

◗ Section 2.3: Modificationof the build-torequirements may berequested or approved bystaff if such modification isfor either a purpose that 1)furthers the urban designgoals of the downtownarea, or 2) the provision ofa public open space thatmeets established criteriafor the location and designof such space. For thepurpose of these standards,public open space isdefined as plazas, courts,parks and similar spacesprovided for the use andenjoyment of the public.

◗ Section 2.3 a: Build-torequirements will not beenforced in situationsinvolving the restoration ofthe lower levels oradditions to the upperlevels of existing buildings.

◗ Section 2.3b: Wherebuildings are locatedwithin or up to thebuild-to zone adjacent tolight rail stops, doors shallbe provided giving directaccess to that stop.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


8


RECESSED ENTRIES ARE EXCLUDED FROM THEBUILD-TO REQUIREMENT - NOT TO EXCEEDWIDTH OF DOORS & TYPICAL SIDELIGHTS

FRONTAGE WHICH MEETS THE BUILD-TOREQUIREMENTS

BUILD-TO ZONE

BUILDING ONE

BUILD-TO ZONE

PROPERTY LINE

FRO

NTA

GE

A

FRONTAGE B

65%

OF

A

65%

OF

A

65% OF B

FRONTAGE C

65% OF C

BUILDING TWO

ILLUSTRATION 3A — BUILD-TO DEFINITION

PROPERTY LINE

FRO

NTA

GE

A

ILLUSTRATION 3B — BUILD-TO requirements

D E S I G N S TA N D A R D S ◗ “ T H E C O O K B O O K ”

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Section 2: Building

Placement & Access

(continued)

Arcades and Entries

For the purposes of thissection, an arcade is a linearuninclosed portion of abuilding which adjoins, andextends the width of thesidewalk parallel to a publicstreet. It is spatially definedon its exterior face by columnssupporting upper floors of thebuilding and on its interiorface by the facade of theground floor

Intent: Allow the exterior faceof the column line of anarcade to satisfy the “build-to”requirement if 1) the arcadecolumn line satisfies thearchitectural scalingrequirements of Section 3within the build-to zone; 2)the arcade is shallow ratherthan deep in order to create alight and inviting space; and3) it doesn’t separate retailfrontage from pedestriantraffic and exposure.

◗ Section 2.1b: The locationof the interior enclosurewall of an arcade may beexcluded from the‘Build-To’ requirements if:1) the exterior boundary ofthe arcade is defined bycolumns located within theBuild-To Zone; 2) theexterior plane of thearcade’s columns generallycontinues the plane of thebuilding facade above(Illustration 4A); 3) thecolumns may not bespaced further than 30 feetapart; 4) the depth of thearcade measured from thefront face of the columnsto the face of the groundfloor facade is no morethan two-thirds of theaverage clear height of thearcade (Illustration 4B); 5)the minimum depth of thearcade is 5 feet, measuredfrom the back face of thecolumns to the groundfloor facade.

Not Applicable ◗ Section 2.3c: An arcademay only adjoin the 16thSt. Mall so long as itsexterior columns arelocated on or within 18inches of the 16th St.property line.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


10

PLANE OF ARCADE COLUMNSCONTINUES THE PLANE OF THEFACADE ABOVE

EXTENDS SIDEWALK PEDESTRIAN CIRCULATION WIDTH

Note: a lower floor facade that is recessed below the upper floorsof a building but does not have columns defining its exterior face,is not considered to be an arcade, and therefore may not beexcluded from the ‘Build-To’ requirements of Section 2.1.

INTERIOR ENCLOSUREWALL OF THE ARCADE

EXTERIOR FACE OF THEARCADE COLUMN LINE

ARCADE HEIGHT

ARCADE DEPTH5' MIN.

2/3 ‘X’

‘X’



11

ILLUSTRATION 4B — ARCADE PROPORTIONS

ILLUSTRATION 4A — ARCADE REQUIREMENTS

Section 3: Architectural

Scaling Elements

Facade Detail and Variety

Intent: Create a varied andhuman scaled architecturalexpression at the lower levelfacades of buildings in orderto improve the comfort andinterest of the pedestrianenvironment.

Intent: Create texture andrelief in the lower facades ofbuildings, taking advantage ofDenver’s sunny climate tobring out changes in plane,material and detail throughthe interplay of light andshadow.

Entries

Intent: Emphasizestreet-related entries toimprove the legibility andconvenience of the pedestrianenvironment and to providevariety of architecturalexpression.

◗ Section 3.1: A minimumof 50% of the glazed area(as measured to the face ofthe frame of the glazingsystem) of the ground floorfacade shall be set back atleast 4" from the solid wallplane of that facade.

◗ Section 3.1a: Entries toground floor pedestrianactive uses and buildinglobbies shall beemphasized throughchanges in plane,differentiation in materialand/or color, greater levelof detail, and enhancedlighting, as well aspermanent signage.

◗ Section 3.2: A minimumof 50% of the glazed area(as measured to the face ofthe frame of the glazingsystem) of the upper floorfacades shall be set back atleast 4" from the solid wallplane of that facade.

◗ Section 3.2a: Theexpression of entry on alarge urban building mayinvolve more than thedesign of the ground floor.The arrangement offenestration, materials anddetails should provideemphasize and identityappropriate to the scale ofthe public environmentand the scale of thebuilding.

◗ Section 3.3: Ground floorrecessed glazingrequirement may bewaived where it can beshown to adversely affectthe implementation ofretail or other pedestrianoriented display and accesssystems.

◗ Section 3.3a: The requiredarea of recessed glazing atthe upper levels may be ina single large feature ordistributed amongnumerous glazed areas.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


12

LOWER FLOORS

VERTICALLY REPEATINGGROUP TWO OPTION:Architectural detail creatinga change in plane - 1" wide x1"deep minimum

HORIZONTALLY REPEATINGGROUP TWO OPTION:Expression of an architecturalbay through a change inplane - 4" deep x 8" wideminimum

HORIZONTALLY REPEATINGGROUP ONE OPTION:Expression of anarchitectural bay through achange in plane - 12" wide x4" deep minimum

VERTICALLY REPEATINGGROUP TWO OPTION:Architectural detail creatinga change in plane 1" wide x1" deep minimum

VERTICALLY REPEATINGGROUP ONE OPTION: Texture change

ILLUSTRATION 5 — APPLICATION OF SCALE ELEMENT OPTIONSSee Scale Element Options -

HORIZONTALLY REPEATINGGROUP TWO OPTION:Architectural detail creating achange in plane - 1" wide x1"deep minimum

Glazing recessed 4" min.

UPPER FLOORS

Glazing recessed 4”


13



Scaling Elements

(continued)


Intent: Architectural scalingtechniques shall be used toexpress an organized varietyof architectural divisions andto avoid large areas ofundifferentiated or blankfacade. Specifying a maximumdimension betweenarchitectural elements is notintended to favor a repetitivespacing, but merely to insurethe occurrence of a minimumamount of change.

◗ Section 3.1b: For anyfacade adjacent to a publicstreet, each floor mustinclude a pattern of at leastthree scaling elements, ofwhich at least one must befrom Group Two (othersmay be from Group One)and one must repeathorizontally (others mayrepeat vertically).(Illustration 5)

◗ Section 3.2b: For anyfacade adjacent to a publicstreet, each floor mustinclude a pattern of at leastthree scaling elements, ofwhich two must be fromGroup Two (others may befrom Group One) and atleast one must repeathorizontally (others mayrepeat vertically.(Illustration 5)

◗ Section 3.2c: A large areachange in facade form orarchitectural expressionincorporating a minimumof two bays in width, andtwo floors in heightreduces the required scalingelements by one within thearea of change.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


14


15

SCALE ELEMENT OPTIONS1 2 3

HORIZONTALLY REPEATING • • • SCALE ELEMENTS: | | |

SCALE ELEMENT OPTIONS3 • ———

VERTICALLY REPEATING 2 • ——— SCALE ELEMENTS: 1 • ———

GROUP ONE OPTIONS

REPEATS AT LEAST ONCE WITHIN EVERY 30HORIZONTAL FEET OF EACH FLOOR’S FACADE:

• Expression of architectural or structural bay through achange in plane at least 4 inches deep, and at least 12inches wide (such as a pilaster).

• Color change.• Texture change.• Material module change.• Architectural ornament integral to the building

materials.• Art work integral to the building’s form or facade

(minimum size: 2 square feet in area at the groundfloor, 9 square feet in area at the upper floors)

GROUP ONE OPTIONS

REPEATS VERTICALLY AT LEAST ONCE IN EACHFLOOR’S FACADE:

• Color change.• Material module change.• Texture change.• Architectural details creating a change in facade plane

at least 4 inches deep.• Architectural ornament integral to the building

materials.

GROUP TWO OPTIONS

REPEATS ONCE WITHIN AT LEAST EVERY 15HORIZONTAL FEET OF EACH FLOOR’S FACADE:

• Expression of architectural or structural bay through achange in plane at least 4 inches deep, and at least 8inches wide.

• Color change.• Texture change.• Material module change.• Architectural details creating a change in facade plane

at least 1 inch deep, and at least 1 inch wide.• Recessing more than 50% of the required glazed area at

least 4" on at least two edges.

GROUP TWO OPTIONS

REPEATS VERTICALLY AT LEAST TWICE IN EACHFLOOR’S FACADE:

• Architectural details creating a change in facade planeat least 1 inch deep, and at least 1 inch wide.

• Color change.• Texture change.• Material module change.• Recessing more than 50% of the required glazed area at

least 4" on at least two edges.

Note 1: The second floor may be designed to meet either the ground floor or the second floor requirements.

Note 2: Mortar color which contrasts with the material, or other clearly visible material joints and reveals (minimum 3/8" wide), arerequired in order to count a material module change as a scaling technique.

Note 3: Removable signage, awnings and other accessories do not count as required scaling elements. However, facades should bedesigned to accommodate these features.

Note 4: Glazed areas do not count as changes in material, color or texture. Glazing frames and mullions may count as scaleelements provided that they are at least 6 inches in width or depth or are of a strongly contrasting color.


Scaling Elements

(continued)


— Relationship to Existing

Buildings of Architectural

and/or Historic Merit

Intent: Relate newdevelopment to existinghistoric buildings in order torespect the quality ofDowntown’s historic heritageand reinforce the significanceof the existing buildings.Relationships should bedeveloped through similarproportions, rhythms anddimensions rather thanimitation of style.

Intent: Coordinate existingand new development toachieve a larger ‘sense ofplace,’ whether it is thereinforcement of theparticular character of astreet, the definition of apublic space, the accentuationof a special building, or thecreation of a gateway ordistrict.

◗ Section 3.3b: If aproposed building isadjacent to an existingbuilding that has beendesignated as a NationalRegister or DenverLandmark building orcontributing structure(subject to Section59-368(1) DesignStandards), the proposedbuilding facade shall reflectthe height and other majorarchitectural features(below 80') of the adjacentbuilding by at least two ofthe following facadeelements: a step-back in thebuilding form (min. 5')reflecting the height of theexisting building; materialor color similarities; similarwindow pattern,alignment, or proportions;reveals, belt courses, orbands of contrastingmaterial or color inalignment with majorfeatures of the adjoiningbuilding.

Section 3.3c: The aboverequirement does not applywhen the proposed projectconsists of restoring theoriginal features of anexisting building.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


16


17

STEPBACK REFLECTSEXISTING HEIGHT

SIMILAR PROPORTIONS

APPROXIMATE ALIGNMENTOF FEATURES

NEW CONSTRUCTION

EXISTING BUILDING

ILLUSTRATION 6 — CREATING RELATIONSHIPS TO EXISTING BUILDINGS OF MERIT



Scaling Elements

(continued)

Materials

Intent: Reinforce the masonrytraditions of Denver andregional architecture. Helpcreate human scaled buildingfacades by encouragingsmaller material modules.

◗ Section 3.1c: All floors to80 feet are required to meetthe same materialstandards; see Section 3.2d.(Illustration 7)

◗ Section 3.2d: All floors to80 feet: Street facing facadeareas, other than glazedareas, shall be constructedof masonry materials orarchitectural metals. For thepurposes of this sectionmasonry materials aredefined as: stone, brick,clay units, terra cotta,architectural precastconcrete, cast stone, andprefabricated brick panels.Not included in thisdefinition are: cast-in-placeconcrete, concrete masonryunits (concrete block), andtile. Architectural metals aredefined as metal panelsystems (either coated oranodized), metal sheetswith expressed seams,metal framing systems, orcut, stamped, or castornamental metal panels.Not included in thisdefinition are ribbed orcorrugated metal panelsystems. Material modules,other than glazing systems,shall not exceed either 5'horizontally, or 3' verticallywithout the clearexpression of a joint.

◗ Section 3.3c: Materialrequirements andlimitations do not apply toconditions where the repairor restoration of an existingbuilding requiresreplacement or replicationof existing materials.

◗ Section 3.3d:“Architectural” cast in placeconcrete may be acceptablewith specific review offinish specifications toensure a quality, highlyfinished surface.

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


18

ILLUSTRATION 7 — USE OF MATERIALS TO ESTABLISH HUMAN SCALE


19


MATERIAL OPTIONSSHOULD BE VARIED

AND MATERIALMODULES EXPRESSED

Section 4:

Wind Mitigation

Generation of excessive

wind drafts by tall

buildings

Intent: Ensure the mitigationof excessive, buildinggenerated wind drafts throughthe encouragement ofmodulated building formsthat disrupt wind flow anddiminish velocity.

◗ Section 4a: Buildings thatare built no more thantwenty feet (20') from anypublic right-of-way and thatare either over 400 feet inheight or are more than200 feet higher than theaverage height of structureswithin 200 feet of any partof the proposed buildingare required to create stepbacks in the building facadethat faces the right-of-waytotaling not less than tenfeet (10') extending across100% of the buildingfacade occurring betweenfifteen feet (15') and eightyfeet (80') above the publicsidewalk. (Illustration 8)

BUILDING

ELEMENTS







◗ ◗ ◗ ◗


20

ILLUSTRATION 8 — REQUIRED STEPBACKS TO MITIGATE WIND AT PEDESTRIAN LEVEL

REQUIRESTEPBACKS

TOTALING 10 FEETMINIMUM ACROSS 100% OF

BUILDING FACE BETWEEN 15' AND80' ABOVE GRADE

EXAMPLE A EXAMPLE B


DESIGN

GUIDELINES

D E S I G N G U I D E L I N E S

21

The following Design Guidelinescorrespond to the intent statements andurban design principles that are found inthe “Cookbook” Design Standards,Section III of this document. They areintended to guide the project designteam and the City’s staff in theevaluation of proposed building projectsin the Downtown B5 zone. Theseguidelines The Design Guidelines areintended to recognize that there may bemany ways in which superiorarchitectural design can meet Denver’surban design goals. These guidelines areto be used as performance standardsagainst which proposed project designscan be evaluated.

Section One:

Fenestration

Downtown is a pedestrian zone. Citysidewalks are the stage and marketplace ofurban life. The lower street related floors ofurban buildings should interact with thepedestrian environment through the welldesigned integration of pedestrian orienteduses and human scaled design elements.

■ Adjacent to the Street Level

Intent: Encourage largely transparent,open and inviting facades at the lowestlevels of the building where it is in directcontact with the pedestrian environment.Street level facades should provide thesetting for pedestrian oriented businessesto engage the interest of people passing onadjacent sidewalks through the inclusionof substantial areas of transparent glazingallowing views into showwindows andbusiness interiors. The area of transparentglazing will generally be expected to exceedthe area of solid wall. Large areas oftransparent glazing may be appropriate atlevels above the street if pedestrianoriented uses such as retail and restaurantsoccur there.

■ Above Street Oriented Floors

and Below Eighty Feet

Intent: Encourage a greater ratio ofsolid wall to window allowing for morevariety of architectural material andform expression, and encouraging theinclusion of human scaled proportionsand elements in fenestration patterns,architectural detail, surface relief,texture and materials (See also SectionThree—Architectural Scaling Elements).


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The area of solid wall surface willgenerally be expected to be greater thanthe glazed area.

■ Building Types Other Than

Retail and Commercial

Intent: Portions of buildings that cannot reasonably include pedestrianoriented uses adjacent to the street dueto use or site constraints and buildingsthat do not utilize regular commercialtype glazing patterns such as parkinggarages should provide variety andhuman scale through the use ofarchitectural proportions, detail, surface relief, texture andmaterials that arecomplimentary totraditional commercialbuildings. (See alsoArchitectural ScalingElements).

Section Two:

Building Placement

The public space of an urban street isgiven shape by the surroundingbuildings. A downtown streetis typicallycharacterized by a regular progression oflarge buildings closely bordering thepublic sidewalk. It is a space that is bothlinear and vertical and its containmentby the mass of buildings around it bothenhances its heightened sense of energyand defines its sense of place. Urbanstreets are more successful market placesand safer pedestrian environments when


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they are active and vital through thepresence of concentrated activity.Different streets within an urban core,such as 16th and 17th Streets inDowntown Denver, have distinctlydifferent qualities that are recognizablein their characteristic scale and profileagainst the sky as seen from the street.

■ Defining Street Space

Intent: Downtown Buildings shouldreinforce the urban characteristics of thestreet by maintaining the majority oftheir lower floor frontage at the edge ofthe public right-of-way. Buildings alongthe street edge should be tall enough toreinforce the urban character of thestreet. Single floor buildings generallyappear too small and out of scale in anurban context. While the excitement ofsome urban streets is in theirmonumental “canyon-like” scale it ispreferred that the 16th Street Mallmaintain a more open atmosphere bystepping back very tall buildings awayfrom the edge of the public right-of-way.

■ Setbacks and Open Space

Intent: Building setbacks to createplazas, arcades or other additions to the

public street space should be specialevents carefully considered to providemaximum public benefits. Setbacks,plazas, arcades, colonnades, galleries,etc. should not dilute or short circuitthe activity of the public sidewalk. Thepublic amenity provided by anyproposed open space should be clearlydefined and provided for in the designof the space. These benefits mightinclude but are not limited to access tosunlight or views, access to publictransportation or deference to adesignated public landmark. Publicopen space should be programmed toencourage a high level of activitythrough interaction with adjacent uses.

■ Frequent Access To and From

the Sidewalk

Intent: Pedestrian activity andpedestrian oriented uses are facilitatedwhen frequent access is provided tobusinesses adjoining the publicsidewalk. Doors from the public walk toindividual businesses should beprovided as frequently as possible ratherthan funneling access through interiorbuilding atriums or courts with limitedsidewalk access.


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Section Three:

Architectural Scaling Elements

The close proximity of massivebuildings and intense pedestrianactivity fosters and rewards greatercomplexity of building form and detail.Urban architecture is perceived at closerange and pedestrian pace.

“Buildings do not move. Light, though, movesover them, and the surfaces change, inlightness, darkness and shadow, and thereforein color. The changes may be slow but arechanges nonetheless, and it would seem thatthe eyes, ever sensitive, are happy to respond.Complex building facades over which light canpass or change make for better streets than domore simple ones.”

~ Allan B. Jacobs Great Streets

■ Human Scaled Building Facades

Intent: Building facades should provideelements of architectural scale andproportion that relate to the human scaleof the pedestrian environment. Largeexpanses of undifferentiated building wallshould be avoided. Facades that provide aregular and frequent pattern of architecturalvariety through such things as modulationof the wall plane, detailing, color, texture,materials and the incorporation of art andornament are encouraged. Buildings shouldtake advantage of the play of light andshadow across their surfaces that theColorado climate provides.

■ Emphasis of Building Entries

Intent: Primary building entries shouldprovide opportunities to create unique,landmark addresses along the streetthrough the use of elements such asdistinctive form, detail, materials, color,ornament, lighting and signage.

■ Relationship to Existing Buildings

of Architectural or Urban Merit

Intent: This issue includes and goesbeyond compatibility with historicbuildings or architectural style. Thecharacter of downtown streets is evidentin the many common rhythms andproportions of the buildings.Opportunities to find common notes, aheight, proportion, material or detailhelp keep the downtown composition intune. This is not intended to encouragehistoric replication.

■ Material Qualities

Intent: Denver and its surrounding regionhave a long tradition of building in stoneand brick. This tradition is complimentaryto the goals of these guidelines in the effortto provide scale, texture, detail and color inthe downtown pedestrian environment.These materials have an inherently humanscaled quality to them derived from theirtraditional shaping and placement byhand. Materials are not limited tomasonry. However the form, scale, detail,


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texture and quality of any materials used inclose proximity to the pedestrianenvironment should be considered inrelation to human interaction.

Section Four:

Mitigation of Wind Drafts

Generated By Tall Buildings

Tall buildings in dense urban contextsare known to generate and accelerateintense wind drafts both through theaffects of their own form and in relationto adjacent buildings. Winds aregenerated in the form of downdraftsoriginating at the upper heights of tallfacades and as drafts funneled betweenclosely adjacent building forms. Slickbuilding skins and large, unvaried wallsexacerbate these problems. Buildingsthat are considerably higher than theirsurrounding context are also notoriousfor creating new high wind impacts onthe surrounding streets.

■ Wind Mitigation Strategies

Large buildings should seek to mitigatepotential hazards and discomfort topedestrians by arying the form andfacades of buildings to disrupt anddiminish wind flow. Downdraftsriginate at the upper floors and can bedefeated by facade step backs, notches,projections and other features.Stepbacks at the lower floors ofbuildings can be particularly effective atdeflecting downdrafts before theyimpact the pedestrian environment.Similarly, horizontal wind velocity canbe diminished through similar variationin building form and wall plane.

Projects over 400 feet must submit ananalysis by an acknowledged expert inwind testing and design stating that thetypical wind patterns generated by theproposed project will not exceed levelscommonly acceptable for pedestriancomfort in the public areas immediatelysurrounding the project.


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A

B C

B C

URBAN WINDS

How high-rise buildings create powerful downdrafts

High-velocitywinds hit cityskyscrapers, shootingturbulent drafts down tostreet level.

Winds blowing across openareas into narrow canyonsbetween buildings pick up speed.

Buildingsitting on a pedestal (onearchitectural solution)diffuses downdraft beforeit hits street

A

Source: From diagram accompanying Scott Armstrong, “Taming the fury of man-made-wind,” Christian Science Monitor (January 15,1985), p23.

C I T Y a n d

C O U N T Y o f

D E N V E R

Approved for Legality:

Robert M. Kelly DateAssistant City Attorney, City and County of Denver

Approved and Adopted:

Marilyn Stokes DateVice-ChairDenver Planning Board

Adopted and published pursuant to Section59-368 of the Revised Municipal Code of theCity and County of Denver and Article VI ofChapter 2 of the Revised Municipal Code ofthe City and County of Denver.

d esign review - denver · 2015-06-22 · sky exposure diagrams, shadow study (if shadow falls on...

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