WEEK 9 JOURNAL ENTRY
DETAILING VOLUME
CONSTRUCTING ENVIRONMENTS
CHAN JOSHUA TIG HAY 638994
REINFORCED MASONRY WALL
METAL PARAPET CAPPING
OPAQUE GLASS GLAZING
ALUMINIUM MULLIONS CONSTRUCTING ENVIRONMENTS
CHAN JOSHUA TIG HAY 638994
DETAILED SECTION
Interrogation of the detailing decisions and purpose A unit-and mullion system is observed from a perspective view of this detail. A one-story high mullion is installed before preassembled wall units are lowered into place behind the mullions. (Ching 8.31) The panel units are glazed units which are opaque as known from the detail section drawing. The glass is glazed from the outside using pressure bars. (Ching 8.32) A reinforced masonry wall sits at the end of the detailed section and acts as the primary structural element of the building. The curtain wall system lies between two reinforced masonry walls due to its non-load bearing nature.
Identification of waterproofing elements The metal parapet capping is the parapet flashing for the wall. (Ching 7.22) Water is allowed to run from a flat parapet top to a sloping roof to the side. The flashing is embedded into the metal roofing beside it so it is also a type of continuous cleat. (Ching 7.20)
Economic implications of decisions By having the glass glazed from the outside is more expensive than interior glazing. Interior glazing is more economical and convenient especially for high-rise buildings, as it is done by using fixed exterior gaskets, interior wedgeshaped gaskets as well as snap-on covers which are easily assembled.
Sustainability and environmental analysis The mullions in this detail are made of aluminium. Although aluminium is recyclable, recycled aluminium is often not preferred by manufacturers because of cosmetic defects and unknown performance properties. (Carey 2010) Also, most building components contain aluminium cladding around another material, which makes separation difficult and thus making a recyclable material not recyclable. Although aluminium has high recyclability, much of the embodied energy is wasted due to the low usage of the processed metal.
CONSTRUCTING ENVIRONMENTS
CHAN JOSHUA TIG HAY 638994
Pros and Cons Using a metal mullion with a shiny surface adds aesthetic value to the building exterior. The parapet flashing is also an effective waterproof element to direct rainwater falling on the roof. One drawback would be the costly usage of the opaque glass of the curtain wall as spandrels.
Where and why things go wrong in this type of detail Problems are likely to occur between the anchors and the mullions of the curtain wall framework. Bolted connections may be subject to rusting if there is not sufficient waterproof membrane to protect the connection.
CONSTRUCTING ENVIRONMENTS
CHAN JOSHUA TIG HAY 638994
REFERENCES Ching, F.D.K 2008, Building Construction Illustrated, John Wiley & Sons, Inc., New Jersey Carey, P 2010, Streamline Material Resourcing, New York viewed 3 October 2013, <http://www.streamlinemr.com/articles/aluminum-how-sustainable-is-it>
CONSTRUCTING ENVIRONMENTS
CHAN JOSHUA TIG HAY 638994