1. Do Now: 1. Update your CAD II Notebooks 2. Answer the following on the Do Now Slide of your Notebooks: Based on what you know about materials used to create exterior walls and the properties of these materials, what do you think are some immediate advantages and disadvantages of using a curtain wall?

2. Curtain Walls

3. What is a Curtain Wall? -A “Curtain Wall” is a non- load-bearing exterior wall that hangs from the face of floor slabs. Construction or cladding material does not define a curtain wall. -Supports its own weight and other environmental forces which act upon it. What do you think some of these environmental factors are? The Seagram Building 375 Park Avenue New York, NY

4. Stick Build System Oldest type of Curtain Wall System Oldest type of Curtain Wall System Materials for stick builds are assembled on site Materials for stick builds are assembled on site Metal plates are use for fastening and adjusted on site to fulfill that building sites requirements. Metal plates are use for fastening and adjusted on site to fulfill that building sites requirements. Each IGU (insulating glass unit) is sealed individually. Each IGU (insulating glass unit) is sealed individually.

5. Unitized System Unitized system uses premade sections to create the curtain wall. Unitized system uses premade sections to create the curtain wall. They are hung from the floor above on preset anchors. (Units are typically one panel wide and one floor tall) They are hung from the floor above on preset anchors. (Units are typically one panel wide and one floor tall) Allows for factory seals in as many critical places as possible. Allows for factory seals in as many critical places as possible. Installed in a sequential manner from bottom to top. Installed in a sequential manner from bottom to top.

6. Factors to Consider Building Movements Building Movements Air Leakage Air Leakage Rain Penetration Rain Penetration Condensation Condensation High Wind Loads High Wind Loads Material expansion and contraction Material expansion and contraction Temperature and Sun Temperature and Sun Willis Tower (Formally Sears) 233 S. Wacker Drive Chicago, Illinois

7. Live Load / Dead Load & Materials Live load – Occupants, materials, equipment, construction, and other elements that don’t necessarily exist at all times. Live load – Occupants, materials, equipment, construction, and other elements that don’t necessarily exist at all times. Dead load – permanent loads that are a product of the structure itself or objects fixed to that structure. Dead load – permanent loads that are a product of the structure itself or objects fixed to that structure. Materials – Many environmental factors can change the shapes and sizes of materials. Compensation for movement needs to be considered just like movement from live loads. Materials – Many environmental factors can change the shapes and sizes of materials. Compensation for movement needs to be considered just like movement from live loads.

8. Air Leakage Ice buildup within a wall during winter months (varies with location) Ice buildup within a wall during winter months (varies with location) Condensation/moisture can corrode fasteners and other elements susceptible to water damage. Condensation/moisture can corrode fasteners and other elements susceptible to water damage. Can lead to IGU being submerged in water in severe cases. Can lead to IGU being submerged in water in severe cases.

9. Rain Protection/Condensation Control - No materials that absorb even the smallest amount of moisture. - No materials that absorb even the smallest amount of moisture. - Various sealants and drainage systems have been created to deter water. - Various sealants and drainage systems have been created to deter water. - Metals are designed and coated to fight corrosion from water. - Metals are designed and coated to fight corrosion from water. - Glazing usually has a powder that absorbs humidity and residual moisture between pieces of glass. - Glazing usually has a powder that absorbs humidity and residual moisture between pieces of glass.

10. High Wind Loads Determined by a building sites engineer, not window manufacturer. Determined by a building sites engineer, not window manufacturer. Calculated by using data involving gust effects, internal pressures, building height, exposure, etc. Calculated by using data involving gust effects, internal pressures, building height, exposure, etc.

11. Glass / Glazing and Thermal Properties Vision Vs. Spandrel Vision Vs. Spandrel What is glazing? What is glazing? Glazing Layers and spacing Glazing Layers and spacing Thermal Properties / Reducing Condensation Thermal Properties / Reducing Condensation

12. Lloyd’s Building 1 Lime Street London, England

13. 497 Greenwich Street New York, NY 390 Park Avenue New York, NY

14. Curtain Wall Fail Read about the causes here

15. Curtain Wall Fail 1895: Montparnasse Station, Paris