NASCLA Accredited Commercial General Contractor flashcards

Methods of cutting metal using heat to melt or vaporize the material, including oxy-fuel, plasma, and laser cutting, chosen based on material, thickness, and required precision.

• Oxy-fuel: Uses oxygen and fuel gas; good for thick carbon steel.
• Plasma Arc Cutting (PAC): Uses ionized gas; high speed, precision, versatile.
• Laser Cutting: Highest precision, minimal heat affect zone, for thinner materials.

Memory trick: Cut Steel: Thermal, Mechanical, Precision Counts.

A thermal cutting process that uses a highly focused, high-power laser beam to melt, burn, or vaporize material, producing very precise cuts with a small heat-affected zone.

• Offers superior precision and intricate cutting capabilities.
• Produces a very narrow kerf and minimal distortion.
• Can cut a wide range of metal thicknesses, with capabilities growing.

Memory trick: Cutting Steel: Laser's Light, Precision's Might.

An electrochemical process that occurs when two dissimilar metals are in electrical contact in the presence of an electrolyte (e.g., moisture), causing the more anodic metal (aluminum) to corrode preferentially.

• Aluminum is anodic to steel, meaning it will corrode when in contact.
• Moisture acts as an electrolyte, accelerating the corrosion process.
• Prevention methods include electrical isolation, barrier coatings, or sacrificial anodes.

Memory trick: Aluminum and Steel: Electrically Separate or Suffer.

Closed structural steel shapes (squares, rectangles, rounds) used in construction, offering high strength-to-weight ratios, excellent torsional stiffness, and resistance to local buckling.

• ASTM A500 is a common specification for cold-formed HSS.
• Efficient for columns, truss members, and architectural exposed structures.
• Superior resistance to local buckling and torsion due to closed shape.
• Connections can sometimes be more complex than for open sections.

Memory trick: HSS: Closed Shape, Stronger Against Buckling.

Checks or cracks that can occur in Glulam beams due to inherent wood properties, drying, or stress, requiring careful assessment to distinguish cosmetic from structural issues.

• Small surface checks are common and usually not structural.
• Cracks can be caused by drying, stress, or manufacturing defects.
• Structural engineer must evaluate any significant or suspicious cracks.

Memory trick: When a Glulam beam shows a frown, call the expert before it falls down.

A water-based wood preservative containing copper and a quaternary ammonium compound, commonly used for pressure-treated lumber.

• Replaced CCA for many residential and commercial applications due to environmental concerns.
• Provides protection against fungal decay and insect infestation.
• Requires specific fasteners (e.g., hot-dipped galvanized or stainless steel) to prevent corrosion.

Memory trick: ACQ's copper and quats keep wood from rot.

Minimum nominal dimensions required for wood columns in Type IV (Heavy Timber) construction as specified by the International Building Code.

• Type IV construction relies on large timber members for fire resistance.
• Minimum nominal dimensions are specified for columns, beams, and arches.
• These dimensions provide inherent fire resistance through charring.

Memory trick: For heavy timber, eight by eight is the column's fate, to meet the code at the gate.

Any alteration made to a pre-engineered roof or floor truss on the job site after its manufacture.

• Strictly prohibited without written approval.
• Can compromise structural integrity and load capacity.
• Requires review by truss manufacturer and structural engineer.

Memory trick: Mess with the truss, and the whole roof might fuss.

Damage to wood characterized by small, round exit holes and fine, powdery sawdust (frass) left by the larvae of powderpost beetles as they tunnel.

• Frass resembles talcum powder or flour.
• Exit holes are typically 1/16" to 1/8" in diameter.
• Infest hardwoods primarily, but some species attack softwoods.

Memory trick: Powderpost beetles leave dust like flour, and tiny holes that show their power.

Wood treated with Chromated Copper Arsenate, a preservative providing long-term protection against decay and insects, primarily used for commercial and industrial ground-contact applications.

• Restricted for residential use since 2003.
• Still approved for many commercial, industrial, agricultural, and marine applications.
• Retention level (e.g., 0.40 pcf) indicates suitability for ground contact.

Memory trick: CCA for commercial ground contact is still grand, but for homes, it's a forbidden land.

A metal connector used to strengthen the connection between roof framing members (like trusses or rafters) and wall plates, primarily resisting uplift forces.

• Also known as seismic or wind ties.
• Crucial in high-wind zones.
• Typically nailed or screwed into both members.

Memory trick: The roof needs a strong hug to stay on when the wind gets rough.

A two-number designation on plywood panels indicating the maximum recommended spacing of supports in inches for roof sheathing (first number) and subfloor (second number) applications.

• Example: 40/20 means 40 inches for roof, 20 inches for subfloor.
• Determined by panel thickness and strength.
• Must match or exceed the framing layout.

Memory trick: Roof first, floor second: that's the span rating's simple word.

Methods for addressing surface imperfections or minor damage on Glued Laminated Timber beams that do not compromise structural integrity.

• Epoxy-based fillers are common for gouges and checks.
• Repairs should match the aesthetic and provide protection.
• Structural damage requires engineering review and specialized repair techniques.

Memory trick: Gouges on Glulam? Epoxy's your friend, for a strong and smooth end.

Maximum allowable dimensions and locations for notches in solid sawn wood joists as defined by building codes to maintain structural integrity.

• Notches reduce the cross-sectional area and strength of a joist.
• Location and depth are strictly regulated.
• Notches are generally prohibited in the middle third of the span where bending moments are highest.

Memory trick: Notches are tricky, 1/6th is the max, holes are 1/3rd, don't relax!

Structural elements capable of spanning significant distances (e.g., 40+ feet) while maintaining the aesthetic and fire-resistive properties of heavy timber construction.

• Glulam is ideal for long spans in heavy timber.
• Solid sawn timbers become impractical at very long spans.
• Requires engineered solutions for structural efficiency.

Memory trick: Long spans need engineered wood's grace, not just a big, old timber's face.

Two horizontal members that cap the top of a framed wall, serving to tie the wall together, provide bearing, and transfer loads.

• Typically uses two 2x lumber pieces.
• Provides continuity across intersecting walls.
• Distributes vertical loads from above to studs below.

Memory trick: The double plate is the wall's belt, holding everything together so it's felt.

Procedures and precautions required to safely and correctly install pre-engineered wood trusses in a commercial building.

• Temporary bracing is critical for stability during and after installation.
• Trusses must be handled carefully to prevent damage.
• Field modifications are prohibited without engineering approval.

Memory trick: Trusses are tricky, brace them quick, or disaster will stick.

The inherent ability of certain wood species to resist degradation by fungi and insects due to natural chemical compounds within the wood.

• Some species like cedar and redwood have high natural resistance.
• Resistance is due to extractives, not density.
• Important for outdoor or ground contact applications.

Memory trick: Cedar's natural shield keeps the bugs away, even when it's wet.

The spacing of fasteners used to attach wood structural panels to framing members, which directly impacts the shear resistance of a shear wall.

• Tighter nailing patterns increase shear resistance.
• Edge nailing is more critical for shear than field nailing.
• Specific patterns are detailed in building codes (e.g., IBC/IRC).

Memory trick: Shear strength is tight, like a well-nailed kite.

Stamps on lumber indicating its moisture content at the time of surfacing (planing) and its resulting dimensional stability.

• S-DRY means Surfaced Dry (19% MC or less).
• S-GRN means Surfaced Green (over 19% MC).
• MC15 means Moisture Content 15% or less.

Memory trick: Stamps tell the story, dry or green, surfaced or rough, for all to be seen.

An engineered wood product made by bonding together multiple layers of wood laminations with durable, moisture-resistant adhesives.

• Allows for larger and longer structural members than solid sawn timber.
• Offers improved strength and dimensional stability.
• Can be manufactured in custom shapes and sizes.

Memory trick: Glulam's strength and size make big spans rise.

Wood impregnated with fire-retardant chemicals to reduce its flammability and rate of flame spread.

• Used to meet specific fire code requirements.
• Can affect structural properties, requiring design adjustments.
• Performance can be sensitive to environmental conditions (heat, humidity).

Memory trick: Fire treatment helps with flames, but your strength might not be the same.

The degradation of metal fasteners when exposed to moisture, chemicals (e.g., from treated wood), or dissimilar metals, leading to loss of strength and structural integrity.

• Electro-galvanized has poor resistance.
• Hot-dip galvanized offers good resistance.
• Stainless steel provides superior resistance.
• Treated wood chemicals accelerate corrosion.

Memory trick: For outdoor wood, choose coatings that are thick and strong, or else your fasteners won't last long.

The fundamental principle for sizing pipes, where Flow Rate (Q) equals Cross-sectional Area (A) multiplied by Velocity (V). This formula helps determine the required pipe diameter for a given flow.

• Q = A * V is the basic hydraulic formula.
• A = π * (D/2)^2 for circular pipes.
• Pipe velocity is often limited to prevent scour or sedimentation.

Memory trick: Quantity equals Area times Velocity: QAV is the key to pipe capacity.

A trenchless construction method used to install pipelines by jacking pipe segments behind a steerable, remotely controlled tunneling machine, with continuous spoil removal.

• Suitable for large diameter pipes (typically >36 inches).
• Offers high accuracy and precise grade control.
• Minimizes surface disruption in urban areas.

Memory trick: Boring for Small, Micro for Big, Bursting for Old, Jacking for New.

A shoring method using interlocking steel or concrete sheets driven into the ground to create a continuous wall, providing robust support for deep excavations, especially near existing structures or in unstable soils.

• Forms a continuous, rigid wall.
• Suitable for deep excavations and unstable soil.
• Protects adjacent structures and prevents groundwater intrusion.

Memory trick: Shoring choices depend on Depth, Soil, Space, and adjacent Structures.

A temporary erosion and sediment control structure designed to detain sediment-laden runoff, allowing suspended solids to settle out before the water is discharged, typically used at the base of slopes or outfalls.

• Detains concentrated runoff.
• Allows sediment to settle.
• Effective at base of slopes or drainage points.

Memory trick: Protecting soil needs layers: surface, flow, and collection for the sediment's stay.

A small, temporary or permanent barrier constructed across a swale, drainage ditch, or channel to reduce the velocity of concentrated stormwater flow, prevent erosion, and promote sediment deposition.

• Reduces flow velocity.
• Promotes sediment settling.
• Commonly made from rock, logs, or sandbags.

Memory trick: Fences for Sheet, Dams for Ditches, Blankets for Bare, Riprap for Rush.

Slope percentage is calculated as (vertical rise / horizontal run) * 100%. To find elevation change, rearrange to: vertical rise = (slope % / 100) * horizontal run.

• Slope % = (Rise / Run) * 100%.
• Used for grading and drainage.
• Ensures proper water runoff.

Memory trick: Slope percent is rise over run, times one hundred, when the grading is done.

OSHA's maximum allowable slope for excavations in Type B soil, which is cohesive soil with an unconfined compressive strength greater than 0.5 tsf but less than 1.5 tsf, or granular non-cohesive soil (e.g., silts, sandy loams).

• Maximum slope: 1:1.5 (horizontal to vertical).
• Equivalent to 34 degrees from the horizontal.
• Applies to trenches 20 feet deep or less.

Memory trick: A is Aggressive (1:1), B is Better (1:1.5), C is Cautious (1:2).

A dewatering and excavation support technique that involves constructing a continuous, low-permeability barrier around an excavation by excavating a trench under a bentonite slurry and then backfilling with impermeable materials (e.g., soil-bentonite, cement-bentonite, concrete).

• Creates a physical, impermeable barrier.
• Prevents groundwater inflow.
• Can also provide excavation support.
• Used in high water table conditions.

Memory trick: Pumps pull water, walls block water, choose your battle with the flow.

A foundation system consisting of concrete piers or piles extending into stable soil, supporting a framework of beams on which the structure rests.

• Elevates the structure above ground.
• Minimizes contact with expansive or unstable soils.
• Commonly used in areas with clay soils or flood risks.

Memory trick: Piers Elevate, Beams Support, Expansive Soils Don't Touch.

A shoring system consisting of vertical steel H-piles (soldier piles) driven or drilled into the ground, with horizontal timber or precast concrete lagging placed between the piles as excavation proceeds.

• Suitable for deep excavations and unstable soils.
• Provides earth retention and can be tied back.
• Commonly used when adjacent structures are present.

Memory trick: Soldiers Lagging in Trenches, Shields for Safety, Hydraulics for Shallow.

A component of a storm drainage system that collects surface runoff and channels it into an underground pipe network, typically featuring a sump to trap sediment and debris.

• Collects surface water.
• Prevents debris from entering pipes.
• Often includes a sump for sediment accumulation.

Memory trick: Catch the Rain, Drain the Debris, Store the Excess.

Bridges constructed from standardized, interchangeable components, designed for quick assembly and disassembly. They are often used for temporary access over obstacles like streams or ravines, minimizing environmental impact.

• Pre-fabricated components.
• Rapid assembly and disassembly.
• Spans obstacles without in-stream supports.
• Minimizes environmental disturbance.

Memory trick: For streams, choose a bridge that floats, not one that digs and bloats.

A dewatering technique that uses a vacuum pump to create negative pressure in a system of wellpoints or drains, effectively extracting water from low permeability soils.

• Ideal for fine silts and clays.
• Increases the hydraulic gradient to draw water.
• Requires airtight connections for efficiency.

Memory trick: Suck the Sludge with Vacuum, Sand is Simple with Wells.

OSHA 29 CFR 1926.652(b)(1)(iii) mandates a maximum allowable slope of 1.5H:1V (1.5 horizontal to 1 vertical) for excavations in Type C soils that are 20 feet or less in depth, when no shoring or shielding is used.

• Type C soil: least stable.
• Maximum slope: 1.5H:1V (approx. 34 degrees).
• Applies to excavations 20 feet or less.
• Requires competent person classification.

Memory trick: A is steep, B is medium, C is flat, for safety, that's that.

The percentage increase in volume of soil after it has been excavated and loosened, compared to its original in-place volume. This factor is crucial for calculating the actual volume of loose material that needs to be handled.

• Loose volume = In-place volume * (1 + Swell Factor).
• Accounts for air voids created during excavation.
• Important for estimating hauling and stockpiling needs.

Memory trick: Cut volume first, then swell, that's the loose amount, to tell.

A type of deep foundation consisting of a large concrete slab covering the entire area of a building, designed to distribute the total load over a wide area, reducing bearing pressure and minimizing differential settlement, especially on soft or variable soils.

• Covers entire building footprint.
• Distributes load over large area.
• Ideal for soft, compressible, or variable soils.
• Minimizes differential settlement.

Memory trick: Foundations match the ground: shallow for good, mat for soft, deep for bad.

A trenchless technology used to install underground pipes, conduits, or cables along a pre-determined bore path, minimizing surface disruption. It's commonly used for crossings under roads, railways, and waterways.

• Trenchless method.
• Minimizes surface disruption.
• Ideal for road, river, or railway crossings.
• Used for new utility installations.

Memory trick: To cross a road, without a trench, bore it straight, no need to wrench.

A dewatering technique that uses submersible pumps placed in drilled wells to lower the groundwater table over a large area, particularly effective for deep excavations in permeable soils.

• Suitable for deep excavations and large areas.
• Effective in permeable soil conditions.
• Uses submersible pumps in drilled wells.

Memory trick: Deep wells for deep problems, wellpoints for puddles, ejectors for clay, sumps for surface play.

OSHA regulation 29 CFR 1926.651(j)(2) mandates that excavated material (spoil piles) must be placed at least 2 feet from the edge of an excavation.

• Minimum 2 feet distance.
• Prevents material from falling into the trench.
• Ensures worker safety and trench stability.

Memory trick: Spoil piles need a two-foot space, for safety in this dangerous place.

Site logistics on a brownfield are dominated by the management of hazardous materials, including safe handling, disposal, environmental monitoring, and strict regulatory compliance, alongside standard construction logistics.

• Involves hazardous material remediation.
• Strict environmental compliance is critical.
• Requires specialized waste disposal and monitoring.
• Worker safety protocols are enhanced.

Memory trick: Brownfield logistics: HAZMAT, COMPLIANCE, SAFETY, then CONSTRUCTION.

An active mitigation system that uses a fan to draw air from beneath a building's concrete slab, creating negative pressure to prevent soil gases (like radon or VOC vapors) from entering the indoor environment.

• Creates a pressure differential to prevent vapor entry.
• Commonly used for radon and VOC vapor intrusion mitigation.
• Includes a fan, piping, and a sealed slab.

Memory trick: Sub-Slab Sucks Vapors Out, Barriers Block Them.

A non-destructive excavation method that uses pressurized water to liquefy soil and a powerful vacuum to remove the slurry, ideal for safely exposing underground utilities and working near sensitive structures like tree roots.

• Uses pressurized water and vacuum.
• Minimizes damage to existing utilities and roots.
• Safer alternative to mechanical excavation in sensitive areas.

Memory trick: When digging near a tree, use water and air, to keep the roots free.

A fire alarm system where each initiating device (smoke detector, pull station) or module has a unique electronic address, allowing the control panel to identify the exact location of an alarm or fault.

• Provides precise location of event.
• Faster response times.
• More flexible and scalable than conventional systems.

Memory trick: Addressable Alarm Accurately Announces Area.

A type of fire sprinkler system designed to suppress-rather than just control-high-challenge fires, particularly in high-piled storage occupancies, by delivering a high volume of water rapidly with large droplets.

• Designed for high-challenge fires (e.g., high-piled storage).
• Aims for fire suppression, not just control.
• Uses large orifice, high-output sprinkler heads.
• Reduces or eliminates in-rack sprinklers.

Memory trick: ESFR Extinguishes Swiftly, Forcing Rapid Response.

A type of twisted-pair cable that includes an outer metallic foil or braid shield to protect the internal wire pairs from electromagnetic interference (EMI) and crosstalk, enhancing data integrity and speed.

• Offers excellent EMI resistance.
• Supports higher data rates over longer distances.
• More expensive and harder to install than UTP.
• Requires proper grounding for shielding to be effective.

Memory trick: Shielded Twists Stop Static, Speeding Data Safely.

A plumbing device installed in the drainage system of food service establishments designed to intercept and retain fats, oils, and grease (FOG) from wastewater before it enters the public sewer system.

• Prevents sewer blockages and backups.
• Required by plumbing codes for commercial kitchens.
• Must be regularly cleaned and maintained.

Memory trick: Grease Interceptor Grabs Grease, Guarding Drains.

For continuous loads (expected to operate for 3 hours or more), the overcurrent protection device must be sized at least 125% of the continuous load, or the continuous load must not exceed 80% of the OCPD rating.

• Applies to loads operating for 3+ hours.
• OCPD must be 125% of continuous load.
• Continuous load must be 80% or less of OCPD rating.
• Prevents overheating and ensures safety.

Memory trick: Continuous Current Cuts Circuit Capacity by 20% for Safety.

An HVAC system that varies the volume of conditioned air delivered to different zones based on their individual heating or cooling demands, optimizing energy use and providing precise temperature control.

• Energy efficient for multi-zone buildings.
• Provides individual zone temperature control.
• Reduces fan energy consumption.

Memory trick: Varying Air Volume Ventilates Vigorously for Versatile Zones.

A device installed in a closed-loop hot water system to absorb the volumetric expansion of water as it is heated, preventing excessive pressure buildup and protecting system components.

• Required for closed-loop hot water systems.
• Protects water heaters and plumbing fixtures.
• Contains a diaphragm and air cushion.

Memory trick: Hot Water Expands, Tank Absorbs, Pressure Drops.

An electronic device that controls the speed of an AC motor by varying the frequency and voltage of its power supply, offering energy savings, precise process control, and reduced mechanical stress during startup.

• Controls motor speed and torque.
• Enables soft starting and stopping.
• Saves energy in variable-load applications.
• Reduces mechanical wear on equipment.

Memory trick: VFD Varies Frequency, Vital for Gentle Starts.

The National Electrical Code (NEC) requires reducing the allowable current-carrying capacity (ampacity) of conductors when they are installed in ambient temperatures significantly higher than 30°C (86°F) to prevent overheating.

• Conductors dissipate heat less effectively in high ambient temps.
• Derating factors are applied from NEC Table 310.15(B)(2)(a).
• Prevents insulation degradation and fire hazards.
• Higher temperature-rated insulation can mitigate some derating.

Memory trick: Hot Wires, Heavy Work, Hence Lower Current.

An international standard for digital communication networks that control lighting in building automation. It enables individual control, grouping, and scene setting for lighting fixtures, offering high flexibility and energy efficiency.

• Individual control of light fixtures.
• Precise dimming capabilities.
• Supports lighting scenes and groups.
• Open standard for interoperability.

Memory trick: DALI Delivers Dynamic, Detailed, Dimmable Illumination.

A type of stone masonry that uses irregular, rough, or natural-shaped stones, often laid without continuous horizontal courses, contrasting with finely dressed ashlar masonry.

• Stones are unshaped or roughly shaped.
• Joints are often irregular.
• Can be 'random rubble' (no courses) or 'coursed rubble' (roughly leveled courses).
• Economical due to minimal stone dressing.

Memory trick: Ashlar is 'A'rtful, Rubble is 'R'aw.

The temporary deformation or bending of formwork components under the weight and pressure of fresh concrete before it hardens.

• Must be limited to maintain dimensional accuracy.
• Affects aesthetics and structural alignment.
• Calculated based on material properties and load.

Memory trick: Deflection kept low, so the structure won't show a bow.

The ordered series of operations performed on fresh concrete to achieve a desired surface texture, flatness, and durability.

• Timing is crucial for each step.
• Starts after concrete placement, ends with curing.
• Varies based on desired final finish.

Memory trick: Screed, Float, Wait, Float, Trowel, Cure.

A condition of aggregate or concrete substrate where the pores are filled with water, but no free water exists on the surface.

• Crucial for proper bonding of cementitious repair materials.
• Prevents substrate from absorbing water from fresh mix.
• Achieved by pre-wetting and then allowing surface water to evaporate.

Memory trick: Clean, sound, and just wet enough for a strong blend.

A test performed on fresh concrete to measure its consistency and workability, indicating how fluid or stiff the mix is.

• Measures workability, not strength.
• Uses a truncated cone mold.
• Result is measured by how much the concrete 'slumps' after the cone is removed.

Memory trick: Fresh as a Daisy, Slump away lazy.