construction logbook: week 7

ENVS 10003 CONSTRUCTION LOG BOOK

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Week 7: Detailing Strategies 1 eLearnings

• Detailing Strategies-moisture and thermal protection • Flashing • Eaves • Green Roofing • Exterior Drainage • Exterior Cladding • Thermal Insulation • Vapour Retarders • Internal Air Regulation • Movement Joints


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eLearnings Detailing Strategies

Moisture and Thermal Protection Overview -Range from continuous impervious membranes to overlapping and interlocking pieces of shingles and tiles -Detailing choice depends on factors such as -maintenance , durability, resistance to wind and fire and aesthetics -The entire envelope system must be fitted with detailing protection -Roof must used appropriate protection where there are bends, vents, breaks, or formation of the roof striation i.e. skylights, chimneys -Exterior walls must be protected where there are windows, doors -Interior walls such as cavity or curtain walls utilise interior drainage systems -Combating internal moisture condensation includes the correct placement of thermal insulation, vapor retards, ventilation of concealed places etc.

Potential heat loss is important when assessing the required mechanical services -This can be determined by materials, construction, insulation, enclosure, orientation and location -Thermal expansion and contraction need to be compensated with the appropriate contrition and expansion joints


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Types of Detailing Strategies Eave Flashing -thin, continuous piece of sheet metal to prevent passage of water at an angle or a point -water must work itself upward again the force of gravity to penetrate a joint-this is where flaying is required -required when there is possibility that rain forced wind will force its way up, beneath or through an envelope material -e.g. through the use of wood tiles, composition tiles, slate tiles or concrete tiles

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Vegetated Roofing Consists of the following layers:

• Mix of vegetation • Lightweight engineer soil or growing medium-absorbs up to 40% of the rain • Filter fabric prevents fine grain soil from clogging the drainage layer • Retention layer slows the execs runoff water • Drainage layer-carries execs runoff water • Sheet barrier-protects the waterproof membrane from mechanical abrasion and root

attachment • Supporting roof structure-must have necessary load bearing capacities

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Corrugated Metal Roofing -Span between purlins and beams -Corrugated to enhance rigidity and durability, swell as water drainage

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Roof Drainage 1. The amount of rain a roof must handle is function of the roof area leading to the roof drains or gutters 2. The frequency and intensity of the rainfall in the region -Rain is transported into the relevant discharge point through box or edge gutters-the use of the gutter depends on the slop of the roof

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Horizontal Board Siding • Bevel sliding • Shiplap sliding • Drop sliding

-All fascia boards can b made form timber, concrete or composite materials -All boards interlocks or overlay, minimising weather penetration

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Rendering -Composite or masonry or Portland cement, sand, hydrated lime and mixed with water -Plastic concrete cover that is fire and weather resistance and durable-much like shock-crete -Required expansion and contraction joints to compensate to external temperature

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Thermal Insulation -Control the flow and transfer of heat through the exterior assemblies of a building and thereby prevent excessive heat loss List of common insulation material: Batts-flexible fiberglass material that fit between studs and joists in frame construction-also used as sound insulation

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Rigid Foam insulation-foam insulation board-polystyrene-imperious to water and fire-common under floor insulation-heat, moisture and water barrier-non structural

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Spray polyurethane/liquid foam-injected into wall cavities where it adheres to surrounding surfaces

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Reflective insulation-materials with a high reflectivity, low emissivity i.e. aluminum backed gypsum board-used in conjunction with dead air space-Sisalation

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Vapor retarders -Material of lower permeability installed to prevent moisture from entering and reaching a point where it can con dance into liquid form -Placed close as possible to the warm side of the insulation -Most effective when it is applied as a separate layer of aluminum foil, polyurethane film, or treated paper -placed behind the exterior, permeable surface and acts as internal drainage channels for moisture vapor

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Ventilation -Vapor retarders installed in a seamless manner can result in stagnating air-air ventilation system acts as a positive heat exchange, exhausting interior spaces of moisture -Ventilation is done by:

• motor driven fans • eve vents • crawl space ventilation-located high near the corner to promise cross ventilation

-All openings should be protected from insects and pests

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Movement joints -All material expand and contract in response to temperature change -Joints prevent distortion, cracking, or breaks in the building materials -They need to allow free movement whilst retaining weather functionality Expansion joints: continuous, unobstructed slots constructed between two parts of a building-permitting thermal or moisture expansion

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Control joints: continuous grooves or separations formed in concrete ground slabs and concrete masonry walls to form a plane of weakness and thus regulate the location and amount of cracking


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Isolation joints: divide a large and geometrically complex structure into sections so that differential movement or settlement can occur between the parts -To prevent the passage of water and moisture, joints must be durance, resilient and have both cohesive and adhesive strength -Can be classified accruing to the amount of extension and compression they can withstand before failure

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construction logbook: week 7

Documents

roof drainage

construction log book

detailing protection

roof http

water drainage http

roof structure

roof striation

roof drains