PANAM UNDER GLASS EMERY ROTH & SONS PROPOSAL FROM FEBRUARY 1955 GROPIUS/BELLUSCHI/ ROTH PROJECT DESIGN INSPIRATION + LE CORBUSIER, PROJECT FOR AN OFFICE BUILDING, ALGIERS, 1938 GIO PONTI, PIRELLI HEADQUARTERS, MILAN, 1958 EMERY ROTH & SONS PROPOSAL DIFFERED SIGNIFICANTLY FROM THE FIRMS EARLIER WORK OF WEDDING CAKE BUILDINGS, WHICH WERE VERY PREVALENT IN NEW YORK BEFORE THE 1961 ZONING RESOLUTION WAS ADOPTED. IT BECAME A CUBIC TOWER SHEATHED IN A SIMPLY MODULATED GLASS CURTAINWALL. AS EARLY MODELS SHOW, THE INVOLVEMENT OF GROPIUS AND BELLUSCHI LED TO A MORE CONSPICUOUS MODERN GEOMETRIC TOWER FORM. THEIR DECISION TO ROTATE THE TOWER CREATED THE COMPLETE SEPARATION THAT NOW EXISTS TO THE NORTH AND SOUTH OF GRAND CENTRAL AND MADE 200 PARK AVENUE THE FOCAL POINT IT STILL IS. PIERCING THE TOWER ON EITHER SIDE OF THE NEW YORK CENTRAL BUILDING AND THEN CHISELING BULK AWAY AROUND THE PENETRATIONS CREATES JUST ENOUGH TRANSPARENCY TO ALLOW THE BUILDING TO REMAIN A FOCAL POINT WITHOUT THE COMPLETE REMOVAL OF MASS BETWEEN THE CORE AND THE WINGS. REMOVED FLOOR AREA IS RELOCATED TO GRADUATED UPPER FLOORS TO SUGGEST SKYWARD ASCENSION. THE OUTER GLASS SHEATH RESTORES THE BUILDING TO A SIMPLER GEOMETRY. ADAPTING THE TAPERED FORM OF THE TOWER AS A GEOMETRIC MODULE/MOTIF CREATES A NON-DIRECTIONAL PATTERN ACROSS THE SURFACE OF THE TOWER IN KEEPING WITH EARLY MODELS AND RENDERINGS WHICH EMPHASIZED THE FORM OVER THE SURFACE. APPLIED IN A LARGER SCALE TO THE TOWER ALLOWS FOR MAXIMUM DAYLIGHTING WHILE THE DENSER, SMALLER SCALE AT THE PODIUM CREATES A MORE MONOLITHIC READING MUCH CLOSER TO PEDESTRIAN LEVEL.
SOUTH ELEVATION WEST ELEVATION NORTH ELEVATION
OUTER CURTAIN WALL TYPICAL UNITIZED CURTAIN WALL OPERABLE WINDOW DOUBLE WALL DETAIL SECTION
FACADE OVERVIEW FRITTING A MAJOR ASPECT OF ENERGY EFFICIENT DESIGN FOR HIGH RISE OF- FICE SPACES IS THE REDUCTION OF COOLING LOADS. FRITTED GLASS ALLOWS FOR A FULLY GLAZED BUILDING ENVELOPE WITH REDUCED G- VALUE THANKS TO THE LOWER PERCENTAGE OF TRANSPARENT AREA. THE DIAMOND SHAPED AND DOUBLE CURVED GLAZING PANELS OF THE PANAM S UNDER GLASS TOWER WILL BE FRITTED ALONG THE TOP SEC- TION IN ORDER TO LIMIT THE SOLAR RADIATION AT HIGH SUN ANGLES DURING THE SUMMER MONTHS. IN WINTER TIME, SUN RAYS AT LOWER ANGLE ARE ALLOWED INSIDE THE BUILDING HELPING REDUCING THE REQUIRED HEAT LOADS. DAY LIGHT THE PERCENTAGE OF NATURAL LIGHT IN REGARDS TO THE OVERALL LIGHTING IS AN IMPORTANT QUALITY CHARACTERISTIC OF INTERIOR SPACES. THE ARRANGEMENT OF THE LIGHT-DIRECTING SHADE GUAR- ANTEES THAT LARGE AREAS OF THE BUILDING ARE SUPPLIED WITH DAY- LIGHT. THE ILLUMINATION WITH DAYLIGHT REDUCES THE USE OF ARTIFI- CIAL LIGHT AND THEREFORE ENERGY, REDUCES INTERNAL HEAT LOADS, AND ENSURES A HIGHER COMFORT OF THE USERS. SOLAR SHADING EXTERNAL SHADING DEVICES ARE UP TO 10 TIMES MORE EFFECTIVE THAN INTERNAL SHADING. THE DOUBLE SKIN FAÇADE ALLOWS FOR IN- STALLATION OF SHADING ELEMENTS IN THE CAVITY WHERE WIND SUC- TION AND TURBULENCES ARE ELIMINATED BY THE EXTERNAL GLASS PANE. COOLING LOADS CAN BE SIGNIFICANTLY REDUCED IN SUMMER TIME NATURAL VENTILATION THE DOUBLE SKIN FAÇADE ALLOWS FOR OPENING THE WINDOWS OF THE INNER FAÇADE WITHOUT NOISE OR TURBULENCE ISSUES. DURING MIDDLE SEASONS, A RELATIVELY HIGH DEGREE OF NATURAL VENTILA- TION IS PROVIDED, THEREFORE VENTILATION OPERATING COSTS CAN BE REDUCED. THE BUILDING GETS A HIGH SUPPLY OF FRESH AIR, THE AIR EXCHANGE TAKES PLACE THROUGH OPERABLE WINDOWS. GIVING THE USERS CONTROL OVER THE TEMPERATURE AND INDOOR CLIMATE OF THEIR OFFICE FURTHER INCREASES THE COMFORT LEVEL AND WELLBEING OF THE OCCUPANTS. SOUND PROTECTION IN ORDER TO INCREASE WELLBEING AND PRODUCTIVITY OF OCCU- PANTS, SOUND PROOFING OF THE FACADES IS CRUCIAL. THE DOUBLE SKIN OF PANAM S UNDER GLASS TOWER NOT ONLY ENHANCES THE PERFORMANCE IN REGARDS TO SOUND PROTECTION, BUT ALSO AL- LOWS OPENING WINDOWS WITHOUT INCURRING IN HIGHER SOUND LEVELS AT THE INNER OFFICE SPACES. CLEANING AND MAINTENANCE THERMAL PERFORMANCE THE PROPOSED DOUBLE SKIN FAÇADE IMPROVES THE THERMAL PER- FORMANCE OF THE BUILDING ENVELOPE THROUGH PASSIVE AND AC- TIVE MEASURES. THE INNER FAÇADE ALONE REDUCES THE HEAT LOSS THROUGH THE GLAZING BY APPROXIMATELY 60%. BESIDES THE DOUBLE GLAZED IGU WITH LOW-E COATING, A HIGH PERFORMANCE UNITIZED CURTAINWALL SYSTEM REPLACES THE SINGLE GLAZED THERMALLY UNBROKEN SYSTEM. THE OUTER SKIN ADDS ANOTHER GLAZING LAYER WITH A STRATEGICALLY PLACED FRITTING TO ENHANCE SOLAR SHAD- ING IN THE SUMMER AND CREATES A BUFFER ZONE WITH PRECONDI- TIONED AIR DURING WINTER TIMES. OVERALL THE U-VALUE CAN BE DECREASED FROM 0.86 BTU/HR-SQ FT F TO APPROXIMATELY 0.18 BTU/HR-SQ FT F. FOR CLEANING AND MAINTENANCE ACCESS, 2.5 WIDE WALKWAYS ARE INSTALLED EVERY 5TH FLOOR. PERSONNEL CAN WALK ALONG THE FA- ÇADE IN THOSE AREAS AND LOWER THEMSELVES DOWN IN A BOAT- SWAIN S CHAIR TO REACH ADJACENT FLOORS.
DETAIL SECTION STRUCTURAL CONSIDERATION EXTERNAL SKIN CONSIDERATION THE EXTERNAL FAÇADE IS A REGULAR PATTERN OF DIAMOND SHAPES AND RECTANGULAR LAMINATED GLASS PANELS. USUALLY ON A CURTAIN WALL FAÇADE, THE MULLION IS WORKING IN TENSION, THE UPPER PART FIXED AND THE LOWER PART SLOTTED, ALLOWING SMALL VERTI- CAL DISPLACEMENT. IN OUR CASE DUE TO THE OVERLAPPING PATTERN, WE HAVE TO ALTERNATE AND THEREFORE THE LOAD DISTRIBUTION CHANGES FROM ONE LEVEL TO THE OTHER. TO AVOID POINTS OF DIFFERENT VERTICAL DISPLACE- MENT BETWEEN THE EXTERNAL SKIN AND THE BUILD- ING STRUCTURE, WE INSERT A SECONDARY BEAM FIXED TO THE EXISTING STEEL COLUMNS. THIS CON- CEPT CAN BE EXTENDED FROM THE REGULAR STO- RIES TO THE ATRIUM S FOR THE DIAMOND PANEL, USING A CONCAVE GLASS SURFACE INCREASES ITS RIGIDITY. THEREFORE ITS THICKNESS CAN BE RE- DUCED, RELIEVING THE LOAD ON THE STRUCTURE. FLAT VS CONCAVE PANEL SIMULATION WITH MEPLA A LAMINATED CONCAVE GLASS PANEL 3/5 OUR PROPOSAL DISPLAYS A HIGHLY PERFORMING FAÇADE. THE DOUBLE ENVELOPE OF THE BUILDING ENABLES NATURAL VENTILA- TION. THE OUTER SKIN IS CONCEIVED AS A RAIN SCREEN AND ACTIVATES THE NATURAL VENTILATION. THE INNER SKIN REGULATES THE INTERNAL CLIMATE. STRESSES DISPLACEMENTS TO ACHIEVE OUTSTANDING THERMAL PERFORMANCES, UNITIZED CURTAIN WALL SYSTEM IS CHOSEN FOR THE INNER FAÇADE. UNIT- IZED CURTAINWALL ARE ENGINEERED TO BE FULLY ASSEMBLED AND GLAZED IN A FACTORY ENVIRONMENT. NOT ONLY IT INCREASES THE SPEED OF FIELD ERECTION, BUT IT ALSO PROVIDES DRAMATIC IMPROVEMENTS OF QUALITY FINISHES AND GLOBAL PERFOR- MANCES. TWO MODULUS ARE DESIGNED, ONE INCLUDING OPERABLE WINDOW TO ALLOW AN INDIVIDUAL CONTROL OF THE CLIMATE ENVI- RONMENT. THE CURTAIN WALL ELEMENTS HAVE BEEN DETAILED TO ACHIEVE EXCEPTIONAL THERMAL, AIR AND WATER INFILTRATION PERFORMANCE. THE MODULES ARE TOP SUPPORTED AT SLAB LEVEL AND LATERALLY RESTRAINED AT THE BASE.
INSTALLATION SEQUENCE EXISITING STRUCTURE THE STRUCTURE IS COMPOSED OF STEEL COLUMNS COVERED WITH PLASTER AND STEEL BEAMS SUPPORTING THE PRECAST CONCRETE SLABS. THE EXISTING STRUCTURE IS ASSUMED TO BE SOUND AND IS KEPT FOR THE PROJECT. SECONDARY STRUCTURE THE ARCHITECTURAL PROJECT INTRODUCES AN ADDITIONAL EXTERNAL SKIN, THEREFORE INCREASES THE FAÇADE LOADS. THE EXTERNAL SKIN WILL BE FIXED TO A NEW SMALLER STEEL BEAM, INDEPENDENT FROM THE EXISTING STRUCTURE IN OR- DER TO ALLOW UNCONNECTED DISPLACEMENT. UNITIZED GLAZING SYSTEM THE INTERNAL SKIN IS A UNITIZED CURTAIN WALL MADE OF DOUBLE INSULATED GLAZING UNITS. THE PREFABRICATED MODULES ARE HUNG ALONG THE CONCRETE SLABS TO FORM THE BUILDING THERMAL ENCLOSURE. UNITIZED CURTAIN WALL ALLOW QUICK AND CHEAP INSTALLATION PROCESS AND AN INTERIOR CLIMATE CONTROLLED ENVIRONMENT. EXTERNAL SKIN THE EXTERNAL CURTAIN WALL FRAME IS MADE OF STEEL HOL- LOW SECTION ON WHICH STEEL PLATES ARE WELDED PUNC- TUALLY. THESE ARE FIXED TO THE INNER SECONDARY STEEL STRUCTURE VIA THE STEEL CANTILEVERED ELEMENTS. THE DI- AMOND SINGLE GLAZING PANELS WITH A DOUBLE CURVATURE ARE NON-OPERABLE. THE RECTANGLE GLAZING PANELS CAN BE OPENED FOR NATURAL VENTILATION LEGEND STRUCTURE 1. EXISTING STEEL PILASTER 2. EXISTING W BEAM 3. CONCRETE SLABS 4. NEW SECONDARY BEAM: DOUBLE C PROFILE WELDED STEEL PLATES INTERNAL SKIN: UNITIZED SYSTEM 5. DOUBLE GLAZING UNIT 6. ALUMINUM FRAME 7. STEEL REINFORCEMENT 8. MULLION S FIXATION BRACKET 9. INSULATED PANELS 10.OPERABLE WINDOW EXTERNAL SKIN 11. DOUBLE CURVED SINGLE GLAZING UNIT 12. STEEL FRAME 13. WELDED STEEL PLATE 14. CANTILEVERED STEEL ELEMENT 15. FIXATION BRACKETS
THERMAL PERFORMANCE VENTILATION SCHEME WINTER SUMMER ONE MAJOR ADVANTAGE OF THE DOUBLE SKIN FAÇADE IS THE OPPORTUNITY FOR NATURAL VENTILATION DURING SPRING AND FALL SEASON WHEN THE OUTSIDE TEMPERATURES IN NYC ARE MODERATE. THE OPERABLE WINDOWS IN THE CURTAIN WALL ALLOW THE OCCUPANTS TO HAVE ACCESS TO FRESH AIR WITHOUT ANY NOISE OR TURBULENCE ISSUES. A BUILDING AUTOMATION SYSTEM WILL OPERATE OPENING THE OUTER SKIN TO GUARANTEE IDEAL TEMPERATURES IN THE CAVITY. DURING THE SUMMER SEASON AUTOMATICALLY OPENING THE INTERIOR WINDOWS FOR NIGHT-TIME COOLING WILL REDUCE THE COOLING LOADS OF THE BUILDING S HVAC SYS- TEM. IN WINTER TIMES THE FAÇADE CAVITY CAN BE USED AS A BUFFER ZONE. PRE-CONDITIONED AIR THAT HAS BEEN HEATED UP BY THE SUN ALLOWS FOR INDIVIDUALLY CONTROLLED NATURAL VENTI- LATION WITH WARM FRESH AIR. THE HIGHER TEM- PERATURE OF THE GLAZED CURTAIN WALL SUR- FACE CREATES A HIGHER AMBIENT TEMPERATURE AND THEREFORE INCREASE THE COMFORT LEVEL FOR THE OCCUPANTS. THE LOW SUN ANGLE AL- LOWS FOR NATURAL LIGHT TO REACH DEEPER INTO THE BUILDING, HELPING TO REDUCE LIGHT- ING LOADS. THE MAIN FUNCTION OF THE DOUBLE SKIN IN SUMMER IS TO REDUCE COOLING LOADS FOR THE BUILDING. THE SPACE BETWEEN THE TWO SKINS WILL BE VENTILATED, THROUGH THE STACK EF- FECT WARM AIR WILL VENT OUT AT THE TOP AND COOLER AIR CAN BE DRAWING INTO THE CAVITY FROM THE BOTTOM. OPENING THE WINDOWS FOR NIGHT COOLING CAN BE AN EFFICIENT WAY TO RE- DUCE COOLING LOADS. MORE IMPORTANT IS THE USE OF EXTERNAL SHADING SYSTEMS WHICH ARE LOCATED IN THE CAVITY. THE SOLAR RADIATION REACHING THE INSIDE OF THE BUILDING CAN BE REDUCED BY UP TO 90% IN ORDER TO CONTROL THE STACK EFFECT AND FOR A BETTER SOUND PRO- TECTION, THE FAÇADE WILL BE DIVIDED INTO SEVERAL SEGMENTS OF AP- PROXIMATELY FIVE FLOORS. EACH SEGMENT WILL HAVE OPERABLE UNITS AT THE BASE TO LET IN COOL AIR AND THE TOP TO VENT OVERHEATED AIR. THE DIAMOND PATTERN ALLOWS FOR ALTERNATING THE OPENINGS TO AVOID CROSSING OF EXHAUST AND FRESH AIR. WHERE THE DOUBLE SKIN CAVITY IS TRANSFORMED INTO ATRIA, MULTI-STO- RY VOIDS ARE CREATED AT DIFFERENT LEVELS OF THE TOWER. THESE ATRIA BRING ADDITIONAL DAYLIGHT AND FRESH AIR INTO THE BUILDING. THEY CREATE AREAS WHERE OCCUPANTS CAN ENJOY INTERESTING OUT- LOOKS, BRINGING A RICHNESS TO THE WORKSPACE. FURTHERMORE THE ATRIA GIVE THE BUILDING A SENSE OF TRANSPARENCY AND LIGHTNESS FROM THE OUTSIDE.
ENERGY CONSIDERATIONS IN NYC EXISTING LARGE OFFICE BUILDINGS CONSTRUCTED BEFORE 1980 HAVE THE FOLLOWING BUILDING ENERGY USE BENCH- MARKS: COOLING: 15.5 KBTU/SFT (49 KWH/SQM) HEATING: 14.4 KBTU/SFT (45 KWH/SQM) INTERIOR LIGHTING 16.07 KBTU/SFT (51 KWH/SQM) WATER HEATING: 0.4 KBTU/SFT (1.3 KWH/SQM) VENTILATION: 3.1 KBTU/SFT (10 KWH/SQM) INTERIOR EQUIPMENT 15.94 KBTU/SFT (50 KWH/SQM) IT CAN BE ASSUMED THAT THE CURRENT METLIFE BUILDING HAS SIMILAR VALUES IN REGARDS TO ENERGY CONSUMPTION. MAIN DRIV- ERS FOR THE DEMAND OF ENERGY ARE COOLING, HEATING AND INTERIOR LIGHTING. THE FOLLOWING PARAGRAPH EXPLAINS THE ENERGY SAVING STRATEGIES OF PANAM S UNDER GLASS TOWER. HEATING LOADS HEATING LOADS ARE PREDOMINATELY CAUSED BY HEAT LOSSES THROUGH THE FA- ÇADE. FOR THE METLIFE BUILDING 8.6 KBTU/ SFT ENERGY CONSUMPTION CAN BE ASSO- CIATED WITH THE SINGLE GLAZED BUILDING ENVELOPE. IMPROVING THE GLAZING AND INTRODUCING AN AIR TIGHT CURTAINWALL IN COMBINATION WITH A SECOND EXTERNAL SKIN WILL REDUCE THE HEAT LOSS BY AP- PROXIMATELY 60%. COOLING LOADS THE HIGH COOLING LOADS IN EXISTING OFFICE BUILDINGS CAN BE DIVIDED INTO INTERNAL LOADS AND EXTERNAL LOADS. SOLAR GAINS THROUGH THE FACE MAKE FOR 30% OF THE COOLING DEMAND (4.65 KBTU/SFT), INTERNAL LIGHTS CONTRIBUTE 36% (5.58 KBTU/SFT). THE PROPOSED DOUBLE SKIN FAÇADE ALLOWS FOR AN INSTALLATION OF EXTERNAL SHADING ELEMENTS. THE TRANSMITTED SOLAR ENERGY CAN BE REDUCED BY MORE THAN 90%. FURTHERMORE THE DAYLIGHT DIRECTING SYSTEM WILL REDUCE THE INTERNAL COOLING LOADS FOR ARTIFICIAL LIGHTING BY APPROXIMATELY 20%. VENTILATION A DOUBLE SKIN FAÇADE ALLOWS FOR NATURAL VENTILATION DURING THE SPRING AND FALL SEASONS. IN THE WINTER PRE- CONDITIONED AIR FROM THE CAVITY CAN BE USED FOR VENTILATION AND CONTRIBUTE TO ENERGY SAVINGS. EXAMPLE: SOLAR ENERGY = 1000 W/M² ENERGY SAVINGS GLAZING WITHOUT SHADING G-VALUE (GLAZING) = 0,57 TRANSMITTING SOLAR ENERGY = 570 W/M² THROUGH ALL MEASURES DESCRIBED IN THE PREVIOUS PARAGRAPHS, ENERGY SAVINGS OF 25% OR MORE CAN BE ACHIEVED. INTE- RIOR EQUIPMENT AND LIGHTING HAVE HIGH POTENTIAL FOR IMPROVEMENT IN ORDER TO ENHANCE THE OVERALL PERFORMANCE OF THE BUILDING. GLAZING + EXTERNAL SHADING G-TOTAL-VALUE = 0,05 TRANSMITTING SOLAR ENERGY = 50 W/M² REDUCTION VALUE: FC = 0,05 / 0,57 = 0,08 INTERIOR LIGHTING WITH THE FULL HEIGHT GLAZING THE AMOUNT OF NATURAL DAYLIGHT FOR THE OFFICE SPACES CAN BE INCREASED. IN ADDITION THE DAYLIGHT DIRECTING SYSTEM WILL DIRECT LIGHT DEEPER INTO THE BUILDING AND THE DEMAND FOR ARTIFICIAL LIGHTING CAN BE REDUCED BY APPROXIMATELY 20%, ENERGY SAVINGS OF UP TO 3.2 KBTU/SFT CAN BE EXPECTED.