WEEK 6 Learning Loop Roof Systems
Studio Site Visit Review
Glossary Appendix
LEARNING LOOP Roof systems can be divided into: • Structural steel framed roof • Concrete roof • Truss roof • Light-framed roof • Space frames Structural steel framed roof can be divided into: • Flat: using lighter sheet of metals (roof beams and purlins) or heavy (primary and secondary roof beams) • Slope: Using lighter sheets of metal for roofing • Portal Frame: Using sheet metal finishing (rigid frame, grids, and purlins) Concrete roofs are top sloped, usually towards the drainage system. It is usually coated with waterproof membrane seeing that it has interactions with water (rain).
Trussed roof are the kinds that can span long distances. It is usually made up of either timber or steel. It can also be made slope. Light framed roofs are usually made up of either timber or cold-formed steel. It can be divided into: • Gable roof: Using rafters, ceiling joist or ridge beams • Hip roof: using valley rafters, common rafters, hip rafters, jack rafters, ceiling joist and ridge beams Space frame roof usually span a long distance and apply 3D plate (bolted, threaded, matrix-like).
Metals • Malleable • Have high melting points • Ductile • Not brittle • Have high deformation There are 3 types of metals: • Ferrous • Non-ferrous • Alloys Ferrous metals are can be divided into stainless steel or those with the presence of iron. The ones with presence of iron are magnetic, reactive and it corrodes easily. One solution to prevent corrosion is by galvanization. Non-ferrous metals do not have the presence of iron. • Copper • Tin • Lead • Zinc • Bronze
Alloys can be considered the most efficient and the easiest to use. Alloys are: • Long lasting • Conductive • Can be shaped easily (into columns, wires, beams, panels)
STUDIO SITE 1 – 12 DAVID ST., ALTONA The building (construction site) is planned to be a 2-storeys residential house with 4 bedrooms and a garage. The building is going to be both mass and frame construction. Frame construction is going to be applied for the roof structure. The foundation of the building is mostly made up of in-situ concrete slabs overlaying one another, thus a 2layer concrete slab foundation. It is quite thick. There are circular-shaped gaps on the foundation, those are for support columns that are not yet to be placed to support the loads from the ceilings and the roof. The wall is made up entirely of concrete bricks,
The concrete bricks are made up entirely of concrete. Those kinds of bricks are made not on site. Some kinds of the bricks are that they are made hollow or with holes on them. The main reason is so that steel beams can be put in them for reinforcement. Then the gap is filled with liquid concrete. The second reason is that so the bricks weight less. The drainage system can start to be seen with pipes on the foundation slabs connected to one major pipe under the foundation. This is then connected to sewers and storm-water pipes.
SITE 2 – APARTMENT BUILDING IN STEPHAN ST., YARRAVILLE The building (construction site) is an apartment building. It is made up of 3 levels; 2 residential levels and 1 underground / basement car park. The building component is mostly made up of concrete as the main material and timber for the terrace area of the units. The building also has a very well thought of drainage system which is connected directly to the sewerage system of the village / area. During the construction process safety precautions and actions are done on site. On the construction site there can be seen the use of scaffolding and retaining column for temporary support.
SITE 3 – 5 GARDNER ST., BOXHILL
walls.
walls.
The building (construction site) is a renovated area of an existing house. The owners themselves are still living normally in the area of the house that is not renovated.
The base area of the roof is made larger than the area of the main building, creating a kind of ‘canopy’ and shaded area. On the corners of the extra hanging part of the roof, the external corner is called heap and the internal corner is called valley.
The exterior walls of the building are covered with cement tiles.
The house is a weatherboard style houses built in the 1950s. The building is made of a frame construction. Using timber frames, hardwood timber. The roof is made also out of a timber frame and a truss system is applied. The roof is covered with cement tiles on similar to the house itself. The shape of the roof is a pitch roof with an angle of 25o. The frame and truss system of the roof is made out of softwood with grading. These are prefabricated timber. The truss system on the roof enables loads to be distributed to the external
There are also speed bracings on the construction of the frame of the roof. The water runoff system is designed very well. On the sidewalls of the building there are quad gutters and pops for downpipes. Cement tiles are also arranged considering the movement of water, for the run off (aqua duct).
The internal walls can be load/non load bearing walls. There are hitch to prevents internal walls from moving to the sides but enables up-down movement. All around the frame construction of the building there are flat strap bracing (x shape) of around 1800mm-2700mm (min effective ply bracing: 900) and tensioner clips to give tension each strap.
There is also a storm water system in on the roof to take away water from the roof.
With the overall frame construction, noggins are placed and applied to restrain lateral movements of the timber (twisting). The noggins are staggered.
The original windows are still used. There are lintel placed above each window for top-down loading in the
Particleboards of yellow tank and groove are used for the floors. The lower subfloor applied bearing, joist,
and stumps. Using polyester bats also insulates the floors. For connections bright and galvanized nails are used ( o prevent rusting). Doors and Windows Vicash timber is used for doors. For the windows there is also applied flashing to prevents water from getting into the house. The doors and windows used exterior frames which are held to the subfloor using a stud tie. One of the main problems for the building is termites. In such the each joints is covered with an antcap to prevent termites.
GLOSSARY
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Cantilever: A beam anchored at only one end.
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Eave: The bottom edges of a roof.
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Rafter: A series of sloped structural members (beams) that extend from the ridge or hip to the wall plate, downslope perimeter or eave. It is designed to support the roof deck and its associated loads. 2
Purlin: Any longitudinal, horizontal, structural member in a roof except a type of framing with what is called a crown plate.
Portal Frame: One kind of construction method using steel or steel-reinforced precast concrete although or laminated timber such as glulam. The connections between the columns and the rafters are designed to be moment-resistant so they can carry bending forces.
Alloy: A mixture or solid solution composed of a metal and another element. 7
Soffit: The underside of any construction element. A soffit can be the underside of; • An arch or an architrave • A flight or stairs • A projecting cornice • The side of a chimney • The exposed undersurface of any exterior overhanging section of a roof eave (bottom edge)
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The wall into which loudspeakers are mounted in a recording studio A drop down box used to mount a kitchen ventilation hood under a sloped or high ceiling
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Top Chord: The top member of a truss system, it does not have to be horizontal.
1 Rafter. 3 September 2014. Retrieved from http://en.wikipedia.org/wiki/Rafter 2 Purlin. 15 July 2014. Retrieved from http://en.wikipedia.org/wiki/Purlin 3 Cantilever. 7 August 2014. Retrieved from http://en.wikipedia.org/wiki/Cantilever 4 Portal Frame. 5 September 2014. Retrieved from http://en.wikipedia.org/wiki/Portal_frame 5 Eave. 26 June 2014. Retrieved fromhttp://en.wikipedia.org/wiki/Eaves 6 Alloy. 3 September 2014. Retrieved from http://en.wikipedia.org/wiki/Alloy#cite_note-1 7 Soffit. 5 August 2014. Retrieved from 8 Top Chord Retrieved from http://www.dictionaryofconstruction.com/definition/chord.ht ml