Construction Materials and Techniques: Roofing, Framing, and Insulation, Exams of Personal Health

Download Construction Materials and Techniques: Roofing, Framing, and Insulation and more Exams Personal Health in PDF only on Docsity! COSC 253 Final Exam Review 260 Questions & Answers 2024 Update. "Cool color - Correct answer roofing materials are nonwhite in color but still reflect a significant portion of the sun's radiation by a coating of reflective pigments "Mill" or Heavy Timber Construction - Correct answer •Also known as IBC Type IV Construction in the IBC •Heavy timber (HT) interior structure, with noncombustible masonry exterior walls A Darby - Correct answer used to float areas of the slab that can be reached without the long arm of the bull float Advanced Framing Goal: - Correct answer to reduce the amount of framing lumber and increase energy efficiency Advanced Framing Why? - Correct answer increased thermal efficiency (as much as 30% improved energy efficiency when compared to conventional platform framing) Optimize lumber usage (up to 19% when compared to conventional platform framing Advanced Framing Techniques - Correct answer Also called "optimum value engineering Advantages of Cool Roofs - Correct answer •Cool roofs can lower roof surface temperatures by 50 to 75 degrees on low-slope roofs •Cool roofs reduce building cooling costs by 15 to 25 percent on low-slope roofs •Cool roofs increase the life span of roofing materials •Cool roofs can reduce urban heat island effects Advantages over Light Wood Framing - Correct answer •Versatile, flexible, simple to construct •Noncombustible and immune to insect attack •Dimensionally stable, with consistent material properties Lighter weight Advantages over Site cast Concrete - Correct answer •High-quality forms can be reused hundreds or thousands of times, reducing formwork cost Page 1 of 31 •Concrete mixing and pouring operations can be highly-mechanized •Work is performed in a climate-controlled environment at ground level •Use of Type III Portland cement and steam curing expedites the manufacturing process Angle of Repose - Correct answer •the steepest angle at which a sloping surface formed of loose material is stable •Depends largely on soil type and characteristics Architectural Sheet Metal Roofing - Correct answer Aluminum (right) Metallic-coated steel (zinc- or zinc-aluminum-coated steel) Plain steel Asphalt Composition Shingles - Summary - Correct answer •relatively inexpensive •Available in a wide variety of colors •Moderately fire-resistant •15 to 25 year life expectancy •Covers 90% of single-family homes in North America ASTM C90 Classifications - Correct answer Light-weight blocks •Less expensive to transport and lay •Lower thermal conductivity Medium-weight blocks •Most commonly specified Heavy-weight blocks •More durable •Higher compressive strength •Better acoustical isolation between adjacent spaces ASTM C150 Cement Types - Correct answer Type I: General purpose Types II and V: For concrete in contact with soils or water with high sulfate concentrations Type III: For cold weather construction Type IV: For massive structures, such as dams, ASTM D2487 - Correct answer •Boulder: Greater than 12 inches in diameter - takes two hands to lift •Cobble: Smaller than boulders but larger than 3 inches in diameter - can be lifted with one hand •Gravel: From 3 inches to .187 inches in diameter - individual particles can be lifted between two fingers Page 2 of 31 Brick Sizes - Correct answer there is no truly "standard" brick. They are available in many sizes Building Joints - Correct answer Joints allow movement to occur without damage: •Changes in geometry (height, thickness, etc.) •Openings (doors, windows) •At intervals no greater than 125' in straight walls •At changes in support conditions Building-Integrated Photovoltaic (BIPVs - Correct answer •Conventional building materials laminated with second generation thin-film PV material •BIPVs serve the traditional function of cladding, roofing, etc. as well as the production of electricity from sunlight Built-Up Roofs (BURs) - Correct answer •Oldest type of low-slope roof membrane •Asphalt-saturated roof felts are bedded in hot asphalt •Felts are overlapped to create a multi-ply assembly •Also called a "hot-mop" or "tar and gravel" roof Casting a Concrete Column - Correct answer •Pour the column footing(s) •Install reinforcing steel (rebar) •Install column forms •Place/pour the concrete •Consolidate concrete as needed •Remove the forms Casting a Slab on Grade - Correct answer Next Steps •Strike off or screed •Float •Trowel •Broom finish (optional) •Cure Channels - Correct answer •Bridging, blocking, and other reinforcing and bracing •Also called cold-formed channels Standard sizes Depth ¾ to 2-1/2 inches Width ½ inch Clay and Concrete Tile - Correct answer •relatively expensive •Kiln-dried clay or cast concrete Page 5 of 31 •Available glazed or unglazed •Fire-resistant •Life expectancy: 30 to 75 years • • CM at Risk (CMAR): - Correct answer 1.Delivery of project for a Guaranteed Maximum Price (GMP) 2. Acts as a consultant to the Owner during ×Development ×Design 3. Bids/contracts/performs the construction work 4. Financially at Risk for the work at the GMP Column to Column Connection - Correct answer Column splices are typically located at roughly waist height, to avoid interference with beam-column connections at floor and so that column splices are conveniently accessible to workers standing on the floor deck Column-to-Column Connections - Correct answer Metal bearing plates and embedded anchor bolts are cast into the ends of the columns Commercial Stone building stone is classified into six groups according to ASTM C119 - Correct answer •Granite •Limestone •Quartz-based •Slate •Marble •Other Concrete Basic ingredients - Correct answer •Aggregates: Fine (sand), and Coarse (gravel or crushed stone) •Water: as a general rule, if it is okay to drink, it can be used to make concrete •Portland Cement: most expensive part of concrete Concrete Masonry Units (CMUs) - Correct answer •Stiff concrete mix vibrated into metal molds •Wet blocks immediately turned out onto a rack •Standard nominal size: 8"x8"x16" •Actual size is 3/8 inch less in each dimension Page 6 of 31 Concrete Slabs - Correct answer Slab on Grade A concrete surface, lying upon, and continuously supported by, the ground beneath Concrete Strength - Correct answer •2,500 to 6,000 psi compressive strength •Made with conventional ingredients High-strength concrete: •Greater than 6,000 psi to roughly 20,000 psi Concrete Testing - ASTM C39 - Correct answer Compression Test Cylinders are returned to laboratory, properly cured, and tested at the appropriate times (typically after 7 and 28 days) to verify the compression strength of the concrete Construct Upper-Floor Platform - Correct answer using open web joists provides space for building services (plumbing, electrical, ductwork, etc.) Construction Manager (Fee Based) - Correct answer •Owner hires independent CM to oversee design and construction services provided by multiple entities •Contracts with the owner for a flat fee (usually a % of construction) Control Joint - Correct answer •should be at least ¼ of slab depth •Made by special trowel while concrete is still plastic or by saw cutting later Coped Beam to Girder Connection - Correct answer Steel beam to girder connection Top flanges of beam are coped to allow the tops of beam and girder to be set level Cost Plus a Fee - Correct answer •Owner pays contractor's direct costs plus an added fee for overhead and profit •Contractor is protected from cost uncertainty •Owner assumes more cost risk/savings reward potential Cradle-to-gate analysis - Correct answer Extends from materials extraction through leaving the manufacturer. Ignores delivery to construction site, installation, use, maintenance, and end-of-life disposal. •Easier analysis •Often, the majority of environmental impacts occur during these phases Page 7 of 31 Fastening - Correct answer Self-drilling, self-tapping screws are most common Crimping tools mutually deform parts to be joined Nail-like pins are power-driven Fastening Methods - Correct answer Face Nailing End Nailing Toe Nailing Fiberboard - Correct answer •Made with wood fibers •Generally limited to interior uses Most commonly used form is medium-density fiberboard (MDF Filling and Finish Grade - Correct answer •Filling - Broad term to describe any placing of earth material (e.g., to raise an existing grade) •Backfilling - Refers more specifically to the replacement of earth material to restore it to finished level •Lifts - Filling or backfilling is placed and compacted in "lifts" (may range from 4 to 12 inches) Finish Quality - Correct answer Controlled casting conditions and high-quality forms allow for greater control of surface finishes Fire Protection - Correct answer •Active Protection - A fire protection system that requires some type of action in order to work in a fire event •Passive Protection - A fire protection system that utilizes fire-resistant construction to limit the spread of fire or protect structural members (no action is required for the system to work) Fire Protection of Steel - How? - Correct answer •Concrete encased •Plaster covered •Gypsum board enclosure •Spray-applied insulation •Loose insulation within column cover •Concrete filled Fire Protection of Steel - Why? - Correct answer •above 500 - 600 degrees F, steel rapidly loses strength •At approximately 1,600 degrees, it loses all strength •Fireproofing acts as insulation, protecting structural steel from the heat of fire Page 10 of 31 Fire-retardant treated wood - Correct answer •Chemical salts pressure- impregnated into wood to reduce its combustibility •Used where building code restricts the use of combustible materials Fixed fee (lump sum) - Correct answer •Owner pays an agreed, fixed amount for work to be performed •General Contractor (GC) assumes most financial risk or potential reward Floating - Correct answer Floating Immediately after screening, floating consolidates and smooth’s the slab surface Fluid-Applied Membranes - Correct answer •Applied with roller or sprayer •Seamless and easily formed around difficult geometry such as vents, domes, and other complex shapes •Can also be used as a new membrane over deteriorated roofs Formwork - Correct answer Formwork must be strong enough to Support the weight and fluid pressure of Wet concrete Frame Upper Floor Walls - Correct answer each floor platform makes a convenient work surface for building the next set of walls Furring - Correct answer •Used for bridging, backing, furring •Also called "hat channel" Standard sizes Depth 7/8 or 1-1/2 inches Width 1¼ inches at raised surface, 2½ inches at base Glue-Laminated Wood - Correct answer •Beams made from glued, solid lumber pieces •Size - Almost any desired size can be laminated •Shape - Wood can be laminated into shapes such as curves and angles •Quality - Can be specified and controlled in laminated members Grade Beams - Correct answer Spans between the pile caps or piers, to provide continuous support for the wall above Green Roofs - Correct answer AKA "vegetated roof" is a system of soil and plant material placed over roofing or waterproofing membrane Ground Floor Platform - Correct answer •Sill plates anchored •Girders placed Page 11 of 31 •Floor joists laid •Subflooring applied Hardwoods - Correct answer •from broad-leafed (deciduous) trees •More complex cell structure Often more interesting grain structure/figure Heavy Timber (AKA "Type IV") - Correct answer construction requires heavy timber framing within noncombustible exterior walls Heavy Timber (HT) - Correct answer •Natural economy of wood construction •Aesthetics (color, grain, warmer feel of wood) •Sustainability of wood Heavy Timber Connections - Correct answer Traditional, pegged, mortise and tendon joinery High-lift grouting - Correct answer •Wall is grouted a story at a time •Some bricks on lowest course are temporarily omitted to create cleanout holes •Cavity is flushed periodically to remove debris Hollow Brick - Correct answer •Lighter in weight •Require less energy to fire •Larger voids can readily accommodate steel reinforcing Hollow Core Slabs - Correct answer •Suitable for intermediate spans •Longitudinal voids replace much of the nonworking concrete Hollow Structural Sections (HSS) - Correct answer •Hollow square, rectangular, round, and elliptical shapes •Made by cold or hot-forming steel strip (sheet) and welding longitudinally How Can Decay/Rot be prevented? - Correct answer •Construct and maintain a wood-framed building so the wood stays dry •Keep wood clear of contact with the ground or concrete foundations •Properly ventilating attics and crawl spaces to remove moisture HT Fire-Resistance - Correct answer large wood members have greater resistance to fire than unprotected steel I-Joists - Correct answer can span further than solid lumber, using less raw material Page 12 of 31 •Bolt tension is verified by inserting a gauge between bolt head and washer Loadbearing Masonry Walls - Correct answer •Carry gravity loads from floors and roofs •May be composite, cavity, or single-Wythe Low-lift grouting - Correct answer •Wall is constructed no more than four feet in height •Vertical reinforcing is installed and left extended 30 bar diameters above wall •Cavity is filled with grout Low-Slope Roof Details - Correct answer •Roof slopes and drain locations are arranged to ensure positive drainage throughout the roof •Crickets and saddles are locally sloped surfaces used to divert water around obstructions in the roof or create slope in level areas Low-Slope Roofs Advantages - Correct answer •A low-slope roof can cover a building of any horizontal dimension •Have a much simpler geometry, often less expensive to construct •When appropriately designed, they can also serve as decks, patios, landscaped areas, or parks Low-Slope Roofs Disadvantages - Correct answer •Water tends to drain slowly from the roof surface •Membranes must be absolutely watertight (small errors can be costly!) •Membrane materials are limited • Low-Slope Roofs - Correct answer •Slope of less than 2:12 (17%) •"Flat roof" is a misnomer - very few roofs are truly flat Lumber Dimensions - Correct answer •In U.S., lumber sizes are given as nominal dimensions in inches Many other standards and programs - Correct answer •U.S. National Green Building Standard (residential building types) •International Green Building Code (model code) •Green Globes (similar to LEED) BREEAM (European program Page 15 of 31 Mass Timber Construction - Correct answer •Mass Timber construction has been used for decades in Europe. However, it is new to North America. The 2021 edition of the IBC will allow this type of construction. Materials Used for Steep Roofs - Correct answer •Wood shingles •Wood shakes •Asphalt/composition shingles •Mineral surface roll roofing •Slate shingles •Clay tiles •Concrete tiles •Sheet metal •Thatch Members that can be precast include... - Correct answer •Slabs •Beams/Girders •Columns •Wall panels •Specialty items (stairs, stadium members, etc.) Metal framing hardware - Correct answer •typically made of sheet metal •Use matching fastener material (stainless steel, galvanized, etc.) •When exposed to the weather, use galvanized steel or stainless steel hardware Mild Steel (Low Carbon Steel) - Correct answer •reasonably strong, highly ductile, and easily welded •Equally strong in tension and compression Model Building Codes - Correct answer IBC and IRC are the models for most U.S. building codes. IRC: •One- and two-family dwellings •Three-stories maximum height •Stand-alone code (includes all aspects of construction) IBC: All buildings not covered by the IRC Modern Steel Construction - Correct answer •Steel is one of three commonly used noncombustible structural materials •Suitable for buildings of all sizes, from single-family residences to the tallest skyscrapers Page 16 of 31 Modified Bituminous Roofing - Correct answer •Sheets of factory manufactured polymer modified bitumen’s •Reinforced with plastic or glass fibers for greater elasticity and durability •Also called "Mod-bit" roof Modular Green Roof Systems - Correct answer •All components of a green roof system above membrane are preassembled in trays •The trays (typically 2 to 4 feet in dimension) are delivered to the jobsite ready to be installed •They are easy to specify, easy to install, and easy to remove or adjust at a later date Moment Connections - Correct answer •Beam flanges are joined to column •Transfers gravity (shear) loads and bending forces to column Mortar - Correct answer •Cushions masonry units, ensuring uniform bearing •Seals joints between the units, minimizing the flow of air and water Adheres units Mortar Admixtures - Correct answer Added ingredients to improve performance or adjust properties: •Pigments, colored aggregate •Accelerators and retarders: Adjust setting time in cold or hot weather •Bond enhancers: Improve flexural strength, freeze-thaw resistance Mortar Joints - Correct answer •Vary from 1/4" to 1/2" in thickness •Standard thickness is 3/8" •Thin joints work for bricks with very small tolerances •Thick joints require a thick mortar that is hard to work Mortar Types: ASTM C270 - Correct answer •Mortar type designations, in order of decreasing strength, come from every other letter in the words "Mason work" •Type S and Type N mortars are the most commonly specified Must Control Settlement - Correct answer Uniform settlement: May disrupt building services entrances or site elements at the building/site interface Differential settlement: May cause damage to finishes, cladding, and other components where building becomes distorted Nails - Correct answer •Inexpensive, fast and easy to install •May be driven by hand or power nail gun Sized in pennies (d), Page 17 of 31 Quarter sawn Lumber - Correct answer •requires more handling of the log during sawing •Not as efficient, generates more waste •Lumber is more dimensionally stable •Produces more pleasing grain figure Radial cracks - Correct answer checks" caused by Tangential shrinkage Radon Gas - Correct answer •Radon is a cancer-causing gas that occurs naturally within soils Rating Cool Roofs - Correct answer •Solar Reflectance - a measure of the material's tendency to reflect solar radiation rather than absorb it •Thermal Remittance - a measure of the material's capacity to radiate infrared heat energy and cool itself Raw Materials - Correct answer Natural clays are excavated from the earth, ground up, and screened to control particle size Reinforcing Bars - Correct answer Rebar is hot-rolled steel, deformed with surface ridges so it will bond with the concrete Residential Roof Problem - Correct answer most roofing failures on composition roofs are caused by improper fastener installation Resists "Wracking - Correct answer Types include... •Wood structural panels (plywood or OSB) •Let-in bracing (1x4 or metal strap) •Structural fiberboard sheathing •Portland cement plaster •Hardboard panel siding Retaining Walls - Correct answer •Hold back soil where an abrupt change in ground elevation occurs •The wall must be strong enough to resist the forces of the earth and any groundwater Rigid insulation installed above the roof membrane - Correct answer •Also known as a "Protected Membrane Roof" or PMR •The membrane is protected from outdoor temperatures •Membrane is immune to moisture blistering problems Rigid insulation installed between structural deck and roof membrane - Correct answer •Traditional position for low slope roof insulation Page 20 of 31 •Protects the deck from outdoor temperatures •A risk with this option is the accumulation of moisture within the insulation Riveting - Correct answer •White-hot fastener is inserted through holes in members to be fastened •Fastener is hammered to produce a head on the plain end Roles in the Steel Construction Process - Correct answer •Steel building frame begins as a rough sketch (Architect) •As design progresses, the sketch evolves to become a finished set of structural drawings (Structural Engineer) Structural drawings are used to prepare detailed shop drawings (Fabricator Roof Ponding - Correct answer Deck structure must not deflect under the weight of standing water such that progressively more water accumulates, leading to "ponding" and possible overloading and collapse. Roof Requirements - Correct answer must be strong and stiff enough to resist loads from water, wind, snow, equipment, people, plants & soil, etc. Roofing and the Building Code - Correct answer •Roof flame spread ratings are classified as either Class A, Class B, or Class C •Class A - Roof coverings that are effective against severe fire test exposure (most fire resistant) •Class B - Roof coverings that are effective against moderate fire test exposure •Class C - Roof coverings that are effective against light fire test exposure (least fire resistant) Rotary Sliced - Correct answer least expensive, finds greatest use in structural applications where appearance is not important Rough Openings - Correct answer •the header supports the loads above the opening •Jack studs (AKA "trimmer") supports the header Rubble Masonry - Correct answer Random: Laid without continuous horizontal joints Coursed: Laid with continuous horizontal joints Sawing - Correct answer •plain sawn: growth rings roughly parallel to wider face of board •Quarter sawn: growth rings close to perpendicular to wider face of board Screws & Bolts - Correct answer Threaded fasteners Page 21 of 31 •Greater holding power than nails •More expensive and time-consuming to install Seasoning - Correct answer •after lumber is sawn, it is seasoned (dried), either in air or in kilns •Kiln drying is generally preferred to air drying •Kiln drying uses more energy but it is faster and produces more stable, uniform lumber •Seasoned lumber is lighter, stronger, and stiffer than green (unseasoned) lumber Selecting Stone for Buildings - Correct answer Considerations •Past history a good predictor of future performance in similar conditions •Petrographic analysis: Microscopic analysis of mineral content and structure •Laboratory Testing: Water absorption, density, compressive strength, dimensional stability, freeze-thaw resistance, chemical resistance, flexural strength, etc. •Locally sourced? Sequential Construction - Correct answer •each major phase begins only after the preceding phase is complete •Design is completed before construction begins Shear Connection - Correct answer •Joins only the web of the beam to the column flange •Transfers gravity (shear) loads from beam to column Shear Studs - Correct answer •Welded to tops of beams, through metal decking •Once concrete is poured, the beams, decking, and concrete act together structurally to form a composite system Shear Walls - Correct answer Masonry or concrete walls can act as shear walls to provide lateral stability Sheet Metal Roofing - Correct answer made from various sheet metals. Materials include: •Lead •Copper •Lead-coated copper •Zinc coated steel •Stainless steel Page 22 of 31 Steel Framing Plan - Correct answer •typically prepared by a Structural Engineer Shows the shape, size, and location of structural steel members Steel History 1750 and Later - Correct answer Growth in use of cast iron framing in industrial buildings and other structures Steel History 1850 and later - Correct answer •Steel increasingly plentiful, with large scale production methods •After the Civil War, steel production capacity sets the stage for the first use of steel in U.S. buildings Steelmaking - Correct answer in a traditional steel mill, iron ore is the raw ingredient. First, it is processed into molten iron in a blast furnace, followed by conversion to steel in a second operation. Steep Roof Defined - Correct answer Slope of 2:12 (17%) or greater Steps in Simple Platform Framing - Correct answer 1.Establish location of building on site 2. Excavation and foundation 3. Construct ground-floor platform 4. Frame ground-floor walls 5. Construct upper-floor platform 6. Frame upper-level walls 7. Frame attic floor and roof Stiff broom - Correct answer may be drawn across the slab surface to create a slip resistant texture Stiff Mud Process - Correct answer •Accounts for approximately 90% of US made bricks Striking off or screening - Correct answer a wood plank or metal straightedge is drawn across the surface of the freshly poured concrete, using an end-to- end sawing motion. Structural Composite Lumber - Correct answer •Laminated Strand Lumber (LSL) and Oriented Strand Lumber (OSL). Made from shredded wood strands •Laminated Veneer Lumber (LVL) is made from thin wood veneer sheets •Parallel Strand Lumber (PSL) is made from thin strips of wood veneer •Structural Finger-Jointed Lumber is made from short lengths of solid lumber scrap Page 25 of 31 Structural Properties of Wood - Correct answer •Wood has both useful tensile and compressive strength •Strength varies significantly with direction of grain, species, and presence of knots or other defects •Strength also varies with duration of load, moisture content, chemical treatments, temperature, size and shape Structural Steel Shapes - Correct answer •Wide-Flange (W-Shape): The most commonly used shape for beams and columns •Channels, angles, tees: For trusses, lighter weight framing, and other miscellaneous uses Studs and Joists - Correct answer Wall studs, floor joists, roof rafters, etc. •Depth 1-5/8 to 12 inch •Width 1-1/4 to 2-1/2 inch •Metal thickness 0.018 to 0.097 inch (18 to 97 mils) Surfacing - Correct answer Lumber is surfaced to make it smooth and more dimensionally precise. •Framing lumber: usually surfaced four sides (S4S) •Finish lumber: may be S4S, or surfaced two sides (S2S), the other sides to be sawn and surfaced by the woodworker SWPPP - Correct answer Storm Water Pollution Prevention Plan Tangled fiber "breather mat - Correct answer is another way to provide air circulation under wood shingles/shakes Tension control bolt: - Correct answer •requires the use of specialized tool (shear wrench) •When bolt is adequately tightened, the splined end snaps off •Proper bolt tension is verified by absence of spline •This method allows tightening with access to only one side of the bolt The Construction Process - Correct answer •Fabricator orders material and steel members are prepared for erection •Erector (may or may not be the same as fabricator) assembles structural steel members on site in accordance with shop drawings and construction documents • The Erector - Correct answer •Assembles steel members delivered to the construction site •May or may not be same entity as fabricator Page 26 of 31 •Workers are called ironworkers The Geotechnical (GTECH) report - Correct answer construction site identified the presence of highly-expansive clay. The construction documents call for a concrete slab-on-grade foundation Thermal Insulation - Correct answer •Located below the structural deck •Located in between the structural deck and the roof membrane •Located above the roof membrane Thermal Insulation - Correct answer •Masonry tends to conduct heat which means it is a poor insulator •Therefore, thermal insulation needs to be part of the design for exterior masonry walls •Thermal insulation can be applied to the outside face of a masonry wall, interior face of a masonry wall, or within the wall Thermoplastic Membranes - Correct answer Polyvinyl chloride (PVC): High performance but with environmental and health concerns related to its manufacture and disposal Thermoplastic polyolefin (TPO) is a more recently introduced membrane material with good chemical stability - heat wieldable Thermoset Membranes - Correct answer •Most common type is ethylene propylene dyne monomer (EPDM) •Synthetic rubber •Highly resistant to the effects of heat, UV radiation, and weather Toothed or "gusset" plates - Correct answer •Used to connect wood members in trusses •Effective and economical •Pressed into the surface of the wood members •No drilling or gluing required Topping Out - Correct answer •the last beam is placed at the top of the structure with a degree of ceremony •At the very least, an evergreen tree or flag is attached to the beam before it is lifted into place •A topping-out party is also held Tracks - Correct answer •Top and bottom of wall framing; ends of floor framing •Analogous to top and bottom plates, rim joist in light wood frame construction Page 27 of 31 •Moisture (MC greater than 20%) •Oxygen •Suitable temperature range (between 50 and 95 degrees F) •A food source (wood!) Why Consider a Steep Roof? - Correct answer •It drains quickly, giving wind and gravity little chance to cause a leak •It can be covered with materials that are manufactured and installed in small units (e.g., shingles) •Wide range of materials available •Visual appeal •Roof repairs tend to be relatively simple and straight-forward Why Cool Roofs? - Correct answer •Roofs are exposed to solar radiation daily •Solar radiation is absorbed and converted into heat •Depending upon intensity of radiation, roof surfaces may reach temperatures of 150 degrees or higher •High roof temperatures can lead to overheating of interior spaces, increased energy consumption, and shorten the roof's life span Why Green Roofs? - Correct answer •Protect membrane from UV degradation •Reduce noise transmission •Reduce storm water runoff •Provide natural habitat •Reduce urban "heat island" effect Why Reinforce Concrete - Correct answer Concrete is strong in compression but it has no useful tensile strength—ability to resist stretching force Wide-Flange Shape Designation - Correct answer W10 x 30 W=Wide-flange shape 10=Nominal depth in inches 30=Weight in pounds per lineal foot Wood adhesives and binders - Correct answer •Form bonds that are at least as strong as the members they connect •Rated for full exterior exposure, limited exterior exposure, or interior exposure Wood Shakes - Correct answer •Thicker than shingles •Exhibit a rougher texture •Usually split rather than sawn •May be tapered or uniform thickness ("straight") •Length: 18 and 24 inches Page 30 of 31 Wood-Plastic Composites (WPCs) - Correct answer Made from mixtures of wood fibers and plastics •May be prefinished •Less stiff and greater thermal expansion and contraction than solid lumber •Used for exterior decking, wood trim, etc. Zoning Regulations - Correct answer •Types of allowed activities, such as industrial, commercial, residential, etc. •Density (i.e., number of dwelling units per acre) •Building setbacks (distance from building to property lines) •Parking requirements •Bulk dimensions (building height, footprint, etc.) Page 31 of 31