Key Terms Window Sash – a frame that holds the panes of a window in the frame. Deflection – the process of deflecting Moment of Inertia – the sum of the product that relates to the torque of the structure. Door Furniture – the lock, handle and other object related to the door. Stress – the pressure or tension of the force. Shear force – when one part a body applies a force in one direction and another body applies a force in the opposite direction. This is known as compression force. Openings: Doors & Windows Doors Doors can be part of the theatre of entering. Doorframes can be timer, steel, aluminium. These can be security doors, flush doors or more traditional doors. Aluminium doors are popular in office and commercial buildings. Ly screen can be added to sliding doors to prevent insects from entering and allow a cool breeze. Steels are good for impact interaction.
Windows Windows need to be thought about how they are going to be clean. Windows can be presented in many structures.
Door Frame and Terminology Window Frames and terminology
Formers Silica Curtain walls -‐ windows or exterior wall system? They are a hybrid system, which are window and walling system. City walls normally use this system. It carries its own load and transfers it back to the concrete. You need to make sure the loads are carried around the window rather than through the window. Glass Components Formers are the basic ingredients used to produce glass. Any chemical compound that can be melted and cooled into a glass is a former. Fluxes help formers to melt at lower and more practical temperatures. Stabilisers combine with formers and fluxes to keep the finished glass from dissolving or crumbling. This has a longer life and is more stable.
Fluxes Soda Ash Potash Lithium Carbonate
Stabilizers Limestone Alumina Magnesia
History • I Century BC – Blown Glass • XI-‐XIII centuries – Sheet glass – sliced from blown glass • XVII century – Lead crystal –Lead oxide added to make glass easier to cut • XVII century – Plate Glass – improved optical qualities • 1910 – Lamination – Celluloid layer inserted between two sheets of glass • 1959 – Float glass – molten glass is poured over a bath of molten tin Properties Hardness – High. Can be scratched with a metallic object. Fragility – High. Differs depending on the type of glass (tempered glass is not as brittle as float glass)
Ductility – very low Flexibility/ Plasticity -‐ very high flexibility and plasticity when molten/ low to very low when cooled Porosity/ Permeability – Non porous/ waterproof Density – Medium – High. Approx. 2.7x more dense than than water (more dense than concrete) Conductivity – Transmit heat and light but not electricity. Sometimes used as insulators in electrical system. Durability/Life Span – Typically durable – chemical, rust and not resistant. Reusability/Recyclability – Very high Sustainability and Carbon Footprint – typically high embodied energy and carbon footprint but ease of recycling/reuse makes it a popular sustainable product. Cost – generally expensive to produce and transport. Types & Manufacture Two main types of glass can be distinguished:
Flat glass – (typically sheets of clear or tinted float, laminated, tempered, wired etc.) Shaped glass –(curved, blocks, channels, tubes, fibres) Float glass is not the most common glass production process in the world.
Types 1. Clear Float glass (annealed glass) The simplest and cheapest glass producer available in the market. No further treatment beyond the float fabrication. Ideal in low risk/low cost/small size glazing scenarios. Breaks into very sharp and dangerous shards. 2. Laminated Glass A tough plastic interlayer (PVB) is bonded together between two glass
panes (as in a sandwich). This improves the security and safety of the glass product, as even though the glass can still crack, the sharp fragments tend to adhere to the plastic rather than falling apart. 3. Tempered Glass (toughened glass) Produce by heating annealed glass to approx. 650 degrees, at which point it begins to soften. The surfaces of this heated glass are then cooled (quenched) rapidly creating a state of high compression in the outer surfaces of the glass. As a result the bonding strength is increased by a factor of 4-‐5 times that of annealed glass and makes it break (shatter) into small, pellet shaped pieces rather than sharp shards, improving the safety of the product. Ideal to use in highly exposed situations (balustrades, partitions, facades) or when the sizes required are particularly large. Other Types and Products Tinted glass – useful in sun-‐exposed situations o reduce visible light transfer
Wired glass – similar concept to laminated glass 0 a steel wire mesh is used instead of a plastic film. Traditionally accepted as a low-‐cost fire glass Patterned glass – made with a rolled glass process –typically used when privacy and light are required. Curved glass – this type of glass is produced in moulds that are created to meet the specific design requirements –expensive Photovoltaic glass – with integrated solar cells Glass channels –used in façade systems Slumped and formed glass – used as design features Glass fibre – hair like strands – used in telecommunications. Double and Triple Glazing When we work inside the building, we want it to act as a third skin. We want it moderate the inside temperature. This would help the building from losing heat and gaining heat. In summer, a building need to be shaded effectively because the
double glazing is not so useful in preventing heat transmission, it’s better at losing ambient heat loss. The low-‐e double-‐glazing absorbs the radiant emission. Activity