week 9
Constructing Environments India McKenzie 639 234
WK 9_JOURNAL
In Detail
Detailing decision The use of the glass block windows for the east elevation of the bandroom allows sufficient light penetration without flooding the space with natural light and compromising the lighting facilitites of the stage. Given that the windows face east, the strongest rays would filter through these windows as the sun rises in the morning which is a time when the stage is least likely to be used. Thus, the windows are placed to maximise natural lighting into the dark space without significantly impacting on the operation of the stage when in use. The glazing of the window has also been arranged so that the light is warped upwards into the roof with a manipulation of the concave glazing face of the window. This means that light is cast toward the ceiling of the interior space which is intended to create the illusion of space. The height of the windows is just above eye level from the interior floor level but above eye level from the external ground level which maintains privacy from bystanders outside. The textured glazing of the glass also skews the view to the outside, as seen in the image below, which further emphasises the function of the window as a source of light and not for viewing and outside-inside interactions as windows are usually used for. The depth of the glass block also provides excellent acoustic insulation as the double glazing acts as a sound barrier to the exterior. This is in keeping with the material choice for the wall that is intended to restrict noise pollution to the neighbouring college buildings. Compared to single glaze windows, these glass blocks are a more appropropriate choice for controlling sound.
View through window from the outside
East Facing External Wall
East Elevation
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Composition Each glass block is a hollow translucent square that is construction by “fusing two halves together with a partial vacuum inside� (Ching, 2011, 5.29). As seen in the detail below, the blocks can be stacked to form walls of glass blocks. Whilst there are maximum heights and widths of sections, panels of the blocks can be joined structurall by vertical stiffeners and horiztonal shelves that panelise the segments.
Building process The window blocks have been inserted into a pre-cast concrete panel wall as seen by the speckled hatch in the diagram on the right. The walls window is center glazed and offset from the edge of the wall to prevent water damage and penetration. The concrete tapers and slopes to create a window sill that reduces water exposure. The steel glass block frame is then attached directly to the concrete with a steel channel anchored to the lintel and filled with expansion material on the head jamb to allow for differential movement and settling. The two windows are connected by a 100mm mortar joint and expansion material which allows for deflection in excessive heat conditions. The window is mortared at the sill point and the steel channel secured with reinforcing rods to the walls.
Weaknesses The weakness of this construction is could be due to water infiltration as thhere is little use of silicone sealants which is a common waterproofing material for window openings. For example if water was to pentrate the sill, it is likely that it would enter into the timber sill and plasterboard finish and rot. There are measures in place to avoid this, however, could be insufficient in the case of extreme and consistent rain fall.
In Detail
WK 9_JOURNAL
Pros - Glazing can be manipulated to suit the interior space - Easily fitted into pre-cast concrete walls - Allow light without compromising privacy - Thick double glazing is less fragile - Provides acoustic insulation Cons - Relatively high embodied energy in the wall materials as seen in the graph below. Note: concrete slab in the floor structure and aliminium in the windows. - Limits windows to dimensions of panels - Restrictive formation patterns of glass blocks Sustainability and Environmental Analysis The chart below indicate the greenhosue gas emitted in the production of the buidling materials used. The steel studs and concrete slab walls have a relatively high embodied energy however the longevity of the materials means that there lifespan is longer and therefore more environmentally efficient than replacing materials with shorter life spans. The embodied energy of aliminium and concrete is significant however, is offset Economic Implications Whilst the inittial costs of the materials and labour may be relatively high, the longevity of the materials and the window system is such that its construction will offset the decreased maintenance required.
In Detail