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OBC House Exam practice questions

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Question 1Building Codes and Regulatory Compliance

Under a typical model building code, what is the primary purpose of a building permit?

  1. To satisfy the lender's insurance requirements
  2. To guarantee the workmanship of the finished structure
  3. To confirm that construction documents comply with code before work begins Correct answer.
  4. To transfer ownership of the property to the contractor

Explanation

A building permit is the formal authorization issued after the authority reviews construction documents for code compliance. It establishes a legal record and triggers inspections, but it does not certify workmanship or guarantee outcomes.

Question 2Building Codes and Regulatory Compliance

A building code that establishes minimum requirements for safeguarding life and property is best described as which type of code?

  1. A model code Correct answer.
  2. A performance code
  3. A prescriptive code
  4. A proprietary standard

Explanation

Model codes are developed by standards organizations for adoption by jurisdictions and set minimum life-safety requirements. Once adopted, they become the enforceable law of that jurisdiction. Prescriptive and performance are drafting styles, not the same as a model code.

Question 3Building Codes and Regulatory Compliance

Which occupancy classification typically applies to a building used for the display and sale of merchandise to the public?

  1. Mercantile Correct answer.
  2. Storage
  3. Business
  4. Assembly

Explanation

Mercantile occupancy covers buildings used for the display and sale of merchandise, such as retail stores. Business occupancy covers offices and similar uses, while assembly involves gatherings of people. Storage covers warehousing of goods.

Question 4Building Codes and Regulatory Compliance

In the context of egress, what does the term 'means of egress' refer to?

  1. The continuous and unobstructed path from any point to a public way Correct answer.
  2. Only the exterior exit door of a building
  3. The stairways required for upper floors
  4. The fire-rated corridors inside a building

Explanation

The means of egress is the continuous, unobstructed route of travel from any occupied point to a public way. It includes exit access, the exit, and exit discharge. It is broader than any single door, corridor, or stair.

Question 5Building Codes and Regulatory Compliance

Which of the following is generally required before a certificate of occupancy is issued for a new building?

  1. A property tax assessment for the new structure
  2. A completed final inspection confirming code compliance Correct answer.
  3. A signed lease with the first tenant
  4. A warranty deed recorded with the county

Explanation

A certificate of occupancy is issued after the building official verifies that the completed work complies with the approved plans and code. Final inspections confirm that required systems and life-safety features are in place. Leases, tax assessments, and deeds are unrelated to occupancy approval.

Question 6Building Codes and Regulatory Compliance

A building official may issue a stop-work order when which condition occurs?

  1. The owner requests a change in the construction schedule
  2. The contractor has not yet hired a subcontractor
  3. Work is proceeding contrary to the approved plans or code Correct answer.
  4. The lender has delayed a draw payment

Explanation

A stop-work order is authorized when work is being done in violation of the code or the approved construction documents. It halts activities until the violation is corrected. Scheduling, staffing, and financing issues are not grounds for a stop-work order.

Question 7Building Codes and Regulatory Compliance

What is the role of a fire-resistance rating in building code compliance?

  1. It specifies the maximum occupancy of a room
  2. It sets the required number of fire extinguishers
  3. It measures the flame-spread of interior finishes
  4. It indicates how long an assembly resists fire under a standardized test Correct answer.

Explanation

A fire-resistance rating expresses the period, in hours or minutes, that an assembly withstands a standardized fire exposure. It is used to determine required separation between spaces and structural protection. Flame spread and extinguisher counts are separate requirements.

Question 8Building Codes and Regulatory Compliance

Which document typically establishes the legal authority for a local building code within a jurisdiction?

  1. The architect's specifications
  2. The manufacturer's installation manual
  3. The contractor's license
  4. The adopted ordinance or statute Correct answer.

Explanation

A building code becomes enforceable when a jurisdiction adopts it through an ordinance or statute. That adoption creates the legal authority for enforcement and inspection. Private documents such as licenses and specifications do not confer that authority.

Question 9Building Codes and Regulatory Compliance

A retail store with a calculated occupant load of 240 people has two exits. The code permits the occupant load to be divided so that each exit serves at least half the total. What is the minimum occupant load each exit must be designed to serve?

  1. 120 occupants Correct answer.
  2. 160 occupants
  3. 100 occupants
  4. 80 occupants

Explanation

When two exits are provided, egress capacity must be arranged so that at least half of the total occupant load can exit through each exit. Half of 240 is 120. This prevents a single blocked exit from stranding more than half the occupants.

Question 10Building Codes and Regulatory Compliance

A corridor serving an occupant load of 50 must provide a clear width. If the code requires 0.2 inches of width per occupant with a minimum of 44 inches, what is the required clear width?

  1. 60 inches
  2. 44 inches Correct answer.
  3. 10 inches
  4. 50 inches

Explanation

The calculated width is 50 occupants times 0.2 inches, which equals 10 inches. Because the code sets a minimum clear width of 44 inches, the larger value governs. The corridor must therefore be at least 44 inches wide.

Question 11Building Codes and Regulatory Compliance

A designer is evaluating an alternative method of construction not explicitly described in the code. Which path is generally appropriate?

  1. Proceed without review because the code does not prohibit it
  2. Wait until after construction to request approval
  3. Apply the closest prescriptive provision without documentation
  4. Submit the alternative for approval supported by technical evidence of equivalent safety Correct answer.

Explanation

Codes typically allow alternative materials and methods when the building official finds them equivalent in performance and safety. The applicant must provide supporting technical data for review. Proceeding without approval or documentation risks noncompliance.

Question 12Building Codes and Regulatory Compliance

A building's occupancy changes from a warehouse to a restaurant. What is the most likely regulatory consequence?

  1. Only a business license is required
  2. A change of occupancy review is required to verify compliance for the new use Correct answer.
  3. No review is needed because the structure already exists
  4. The fire sprinkler system may be removed

Explanation

A change of occupancy can increase hazards such as occupant load, egress demand, and fire risk. Codes require review to confirm the existing or modified building meets requirements for the new use. A business license does not substitute for code review.

Question 13Building Codes and Regulatory Compliance

A stairway serving an occupied floor must have a minimum headroom measured vertically from the stair tread nosing line. Which value is commonly required?

  1. 60 inches
  2. 68 inches
  3. 96 inches
  4. 80 inches Correct answer.

Explanation

Stairways typically require a minimum headroom of 80 inches measured vertically from the tread nosing line. This clearance protects occupants from head injury during descent. Other values are either below the minimum or unnecessarily large.

Question 14Building Codes and Regulatory Compliance

A guardrail is required along an open-sided walking surface where the drop exceeds a threshold. Which height range is commonly specified for the top of a guard?

  1. 30 to 36 inches
  2. 42 to 48 inches Correct answer.
  3. 24 to 30 inches
  4. 54 to 60 inches

Explanation

Guards are commonly required to have a top edge at least 42 inches above the walking surface, with a typical maximum around 48 inches. This height helps prevent falls over the edge. Lower heights are insufficient, and higher values are not the standard minimum.

Question 15Building Codes and Regulatory Compliance

Which of the following best describes the purpose of a required fire separation between a garage and a dwelling unit?

  1. To reduce the spread of fire and fumes from the garage into the living space Correct answer.
  2. To reduce noise transmission between rooms
  3. To provide structural support for the roof
  4. To improve the thermal insulation of the garage

Explanation

Separation between a garage and a dwelling limits the migration of fire, smoke, and vehicle fumes into occupied living areas. It is a life-safety measure rather than a thermal or structural one. Noise control is a separate design consideration.

Question 16Building Codes and Regulatory Compliance

A building official finds that an existing structure has an unsafe condition. Which action is within the official's authority?

  1. Transfer ownership of the building to the jurisdiction
  2. Ignore the condition if the building predates the code
  3. Waive all future inspections for the property
  4. Require the owner to correct the condition or vacate the premises Correct answer.

Explanation

Building officials have authority to order correction of unsafe conditions and, where necessary, to require the building to be vacated. This protects occupants from imminent harm. The official cannot seize the property or permanently waive inspections.

Question 17Building Codes and Regulatory Compliance

What does a nonconforming use typically refer to in zoning and building regulation?

  1. A use that was lawful when established but no longer conforms to current rules Correct answer.
  2. A use that is permitted only on weekends
  3. A use that has never received any permit
  4. A use that violates the fire code

Explanation

A nonconforming use was legally established under earlier rules but does not conform to current regulations. Many codes allow it to continue with limits on expansion or discontinuation. It is distinct from illegal or unpermitted uses.

Question 18Building Codes and Regulatory Compliance

A designer calculates that a room's required egress width is 36 inches based on occupant load, but a code section sets a 44-inch minimum for that space. Which width must be provided?

  1. The lesser of the two values
  2. 36 inches
  3. 40 inches
  4. 44 inches Correct answer.

Explanation

Where a calculated width and a stated minimum both apply, the more restrictive requirement governs. The 44-inch minimum exceeds the calculated 36 inches, so 44 inches is required. The lesser value would not satisfy the code.

Question 19Building Codes and Regulatory Compliance

In reviewing a set of construction documents, why does the code require the occupancy classification to be shown?

  1. It determines the building's energy use
  2. It sets the property's resale value
  3. It determines the applicable life-safety, egress, and fire-protection requirements Correct answer.
  4. It establishes the contractor's payment schedule

Explanation

Occupancy classification drives many code requirements, including egress, fire separation, and fire-protection systems. Showing it on the documents allows reviewers to verify the correct provisions are applied. It does not govern value, payment, or energy performance.

Question 20Building Codes and Regulatory Compliance

A building has an occupant load requiring three exits. Which arrangement is generally required to preserve egress reliability?

  1. Exits that share a single discharge corridor
  2. Exits arranged so that a single fire cannot block all of them Correct answer.
  3. All exits located in the same corner of the building
  4. Exits located only through the main lobby

Explanation

Where multiple exits are required, they must be arranged so that a fire or other emergency cannot block access to all of them at once. This is achieved through separation and remoteness requirements. Concentrating exits or sharing a single discharge defeats the purpose.

Question 21Building Codes and Regulatory Compliance

A building official is evaluating whether an existing building meets a new requirement after a code update. Which principle generally applies to existing buildings?

  1. Existing buildings may remain unless the code specifies retroactive requirements or a change triggers compliance Correct answer.
  2. Only buildings constructed after the update are ever inspected
  3. All existing buildings must immediately comply with every new provision
  4. Existing buildings are permanently exempt from all codes

Explanation

Codes generally apply new requirements prospectively, and existing buildings are addressed through specific provisions for existing structures. Compliance may be triggered by alterations, additions, or changes of use. Blanket retroactivity or permanent exemption is not the standard approach.

Question 22Building Codes and Regulatory Compliance

An architect proposes substituting a material with a lower fire-resistance rating than the approved assembly. What is the appropriate regulatory response?

  1. The substitution must be rejected without any evaluation
  2. The substitution requires review and approval showing equivalent performance Correct answer.
  3. The substitution is automatically approved if it costs less
  4. The substitution may proceed because the architect is licensed

Explanation

Substitutions affecting life safety must be evaluated and approved by the building official before installation. The designer may submit evidence demonstrating equivalent or better performance. Licensing, cost, or automatic rejection does not replace that review.

Question 23Building Codes and Regulatory Compliance

A mixed-occupancy building contains both a mercantile area and an assembly area. Which approach is generally used to apply code requirements?

  1. Apply only the most restrictive occupancy to every space regardless of separation
  2. Apply the requirements of each occupancy, with provisions addressing the separation or combination of uses Correct answer.
  3. Apply no requirements because mixed uses are exempt
  4. Apply only the least restrictive occupancy requirements to the entire building

Explanation

Mixed-occupancy buildings are evaluated by applying the requirements of each occupancy, with rules governing whether the uses are separated or treated as a single combined occupancy. The applicable method depends on the building's configuration and fire separation. Ignoring individual occupancy requirements is not permitted.

Question 24Building Codes and Regulatory Compliance

A designer must determine the required fire-resistance rating of an exterior wall based on its distance from the property line. Which factor most directly drives that rating?

  1. The fire separation distance and the wall's exposure to fire Correct answer.
  2. The number of windows on the opposite facade
  3. The building's construction cost
  4. The color and finish of the exterior cladding

Explanation

Exterior wall fire-resistance requirements depend on the fire separation distance between the building and the property line or adjacent building. Greater exposure generally requires more protection. Cost, neighboring windows, and finish color do not determine the rating.

Question 25Building Codes and Regulatory Compliance

A jurisdiction adopts a newer edition of a model code with a local amendment that is more restrictive than the model text. How should the designer apply the requirements?

  1. Follow the model code edition only, ignoring local amendments
  2. Apply the older edition that was previously in force
  3. Choose whichever version is less costly to build
  4. Apply the more restrictive local amendment where it governs Correct answer.

Explanation

When a jurisdiction adopts a model code with local amendments, the amendments become part of the enforceable code for that jurisdiction. Where a local amendment is more restrictive, it governs over the model text. Ignoring adopted amendments or reverting to an older edition is improper.

Question 26Building Codes and Regulatory Compliance

A commercial project is designed under a model building code. Which document most directly governs how the adopted code is interpreted and enforced in that jurisdiction?

  1. The designer's project specifications and drawings
  2. The construction contract's general conditions
  3. The manufacturer's installation instructions for the products used
  4. The locally adopted code edition together with its amendments Correct answer.

Explanation

Enforcement authority flows from the code edition formally adopted by the jurisdiction, as modified by any local amendments. Manufacturer instructions, contracts, and specifications may impose additional obligations, but they cannot override or replace the legally adopted code text.

Question 27Building Codes and Regulatory Compliance

A permit applicant submits plans for a new structure. Under typical code administration provisions, when must a permit be obtained before construction begins?

  1. At the time of the final inspection request
  2. Only after the foundation inspection is scheduled
  3. Within 30 days of the first inspection
  4. Before starting work on the regulated construction Correct answer.

Explanation

Codes generally prohibit commencing regulated work until a permit has been issued, so the permit must precede construction. Inspections and final approvals occur afterward and cannot substitute for prior authorization.

Question 28Building Codes and Regulatory Compliance

During construction, a building official determines that work is proceeding in a manner that endangers the public. Which administrative tool is most appropriate for halting the work immediately?

  1. A variance request
  2. A certificate of occupancy revocation
  3. A notice of violation with a 30-day cure period
  4. A stop-work order Correct answer.

Explanation

A stop-work order is the administrative mechanism used to halt construction that is unsafe or contrary to approved documents. It takes effect immediately and remains until the official confirms the condition is resolved.

Question 29Building Codes and Regulatory Compliance

A designer needs the minimum required fire-resistance rating for a new assembly. Where should the rating be confirmed for a specific tested wall assembly?

  1. The contractor's quality control plan
  2. The project's structural calculations
  3. The approved listing or test report for the assembly Correct answer.
  4. The local zoning ordinance schedule

Explanation

Fire-resistance ratings for specific assemblies are established by standardized fire tests and published listings that identify the tested construction. The code references these ratings, but the assembly details come from the listing or test report.

Question 30Building Codes and Regulatory Compliance

A proposed building will contain a small office area within a larger storage warehouse. Which method is generally acceptable for establishing the occupancy classification of the building?

  1. Assign each area its own classification and apply separation requirements Correct answer.
  2. Classify the entire building as the most restrictive occupancy present
  3. Classify by the occupancy of the largest tenant only
  4. Ignore accessory areas that occupy less than half the floor

Explanation

Where multiple occupancies exist, each area may be classified separately, provided the required fire separations between occupancies are met. Alternatively, the building may be treated as a single occupancy under the more restrictive classification.

Question 31Building Codes and Regulatory Compliance

An occupant load calculation for a 3,000-square-foot assembly space uses a density of 15 square feet per occupant. What is the calculated occupant load?

  1. 200 occupants Correct answer.
  2. 150 occupants
  3. 250 occupants
  4. 300 occupants

Explanation

Dividing the floor area by the occupant density gives 3,000 divided by 15, which equals 200 occupants. The calculated load then drives egress capacity and exit requirements.

Question 32Building Codes and Regulatory Compliance

A corridor in a business occupancy serves an occupant load of 120. If the code requires 0.2 inches of clear width per occupant with a 44-inch minimum, what clear width governs?

  1. 30 inches
  2. 48 inches
  3. 24 inches
  4. 44 inches Correct answer.

Explanation

The calculated width is 120 multiplied by 0.2 inches, equal to 24 inches. Because the code minimum is 44 inches, the larger value governs, so 44 inches is required.

Question 33Building Codes and Regulatory Compliance

A stairway in a means of egress must provide a minimum clear width. Which dimension generally establishes the required stair width?

  1. The width of the landing above the stair
  2. The width of the door at the bottom of the stair
  3. The width of the widest tread measured at the nosing
  4. The width based on the occupant load served, subject to a code minimum Correct answer.

Explanation

Stair width is sized from the occupant load it serves, subject to a minimum established by the code. Door and landing dimensions do not control the stair width itself.

Question 34Building Codes and Regulatory Compliance

A designer is selecting exit signage for a large mercantile space. Which requirement most directly ensures occupants can locate exits during an emergency?

  1. Signs must be printed in at least two languages
  2. Exit signs must be visible and illuminated along the egress path Correct answer.
  3. Signs must be placed at every 50 feet of travel distance
  4. Signs must be posted at the main entrance only

Explanation

Exit signs must be provided and illuminated so they remain visible along the path of egress travel. This ensures occupants can identify the route even during power loss or smoke conditions.

Question 35Building Codes and Regulatory Compliance

A dwelling unit's sleeping room is proposed without an emergency escape opening. Which code principle most directly supports requiring such an opening?

  1. Access for emergency responders to enter
  2. Energy efficiency of the building envelope
  3. A secondary means of escape for occupants during a fire Correct answer.
  4. Structural load resistance during seismic events

Explanation

Emergency escape openings provide occupants, particularly in sleeping rooms, a secondary route out when normal exits are blocked by fire or smoke. They are a life-safety feature independent of responder access or structural design.

Question 36Building Codes and Regulatory Compliance

A project proposes a new type of structural connection not described in the code. Which approach is generally acceptable for demonstrating compliance?

  1. Proceed without documentation because the code is silent
  2. Rely on the contractor's prior experience with similar connections
  3. Submit an alternative means of compliance supported by test data or engineering analysis Correct answer.
  4. Apply the closest prescriptive detail without modification

Explanation

Codes permit alternative materials and methods where the designer demonstrates equivalent compliance through tests, engineering analysis, or other approved evidence. Silence in the code does not authorize unverified construction.

Question 37Building Codes and Regulatory Compliance

A building is being changed from a storage occupancy to a restaurant. Which action is most likely required before the new occupancy may be used?

  1. A demolition permit for the existing structure
  2. A revised site plan only
  3. A new certificate of occupancy reflecting the new use Correct answer.
  4. A zoning variance for the restaurant use

Explanation

A change of occupancy typically requires a new certificate of occupancy confirming the building meets code requirements for the new use. This may also trigger upgrades to egress, fire protection, and accessibility.

Question 38Building Codes and Regulatory Compliance

A designer is evaluating whether an existing building must comply with a newly adopted code edition after a renovation. Which principle generally applies?

  1. Existing conditions may remain unless the alteration creates a hazard Correct answer.
  2. Only fire alarm systems must be upgraded
  3. All existing conditions must be upgraded regardless of scope
  4. The new code applies only to new construction on vacant land

Explanation

Existing building provisions generally allow existing conditions to remain unless the work increases a hazard or triggers specific upgrade thresholds. Full compliance is not automatically required for unrelated existing conditions.

Question 39Building Codes and Regulatory Compliance

A building official must determine whether a proposed occupancy separation is adequate. Which factor most directly determines the required fire separation between two dissimilar occupancies?

  1. The height of the building's parapet
  2. The square footage of the smaller occupancy
  3. The number of plumbing fixtures in each occupancy
  4. The fire-resistance rating assigned to the occupancy pair Correct answer.

Explanation

Where occupancies are separated rather than treated as a single classification, the code assigns a required fire-resistance rating based on the specific occupancy pair. That rating, not parapet height or fixture counts, controls the adequacy of the separation.

Question 40Building Codes and Regulatory Compliance

A designer is calculating the required fire-resistance rating of an exterior wall near a property line. Which factor most directly drives the required rating?

  1. The wall's distance from the property line and its fire exposure Correct answer.
  2. The size of the windows on the opposite facade
  3. The color and finish of the exterior cladding
  4. The building's plumbing fixture count

Explanation

Exterior wall ratings depend on the fire separation distance measured to the property line and the resulting fire exposure. Walls closer to the line generally require higher ratings to limit fire spread to adjacent property.

Question 41Structural Systems and Foundations

Which structural component of a light wood-frame house transfers roof and wall loads down to the foundation?

  1. The floor finish flooring boards
  2. The vertical studs and their sole and top plates Correct answer.
  3. The roof underlayment membrane
  4. The exterior wall sheathing panels

Explanation

In platform and balloon framing, vertical studs carry loads from the roof and upper floors down through the sole plate to the foundation or sill. Sheathing stiffens the wall but is not the primary vertical load path. Finish materials and underlayment have no structural load-carrying role.

Question 42Structural Systems and Foundations

A continuous footing is used under a residential foundation wall primarily to accomplish which purpose?

  1. Spread the wall load over a larger soil area Correct answer.
  2. Anchor the roof trusses to the wall
  3. Drain groundwater away from the slab
  4. Provide a decorative base for the siding

Explanation

A footing widens the bearing area beneath a wall so that the imposed load is distributed over enough soil to stay below the allowable bearing pressure. It is a structural element sized by load and soil capacity, not a finish or drainage device. Drainage is handled by separate perimeter systems.

Question 43Structural Systems and Foundations

In a conventional wood-frame floor, which element spans between the foundation walls or beams and supports the subfloor?

  1. The subfloor adhesive bead
  2. The rim joist cap flashing
  3. The floor joist Correct answer.
  4. The sill sealer gasket

Explanation

Floor joists are the repeated horizontal members that span between supports and carry the floor loads. The subfloor is fastened on top of them. Sill sealers and adhesives are accessory products that do not span or carry load.

Question 44Structural Systems and Foundations

Which term describes the vertical distance a roof surface rises for each unit of horizontal run?

  1. The ridge offset
  2. The overhang
  3. The pitch or slope Correct answer.
  4. The eave line

Explanation

Roof slope is expressed as rise over run, commonly as a ratio such as 4:12 or as pitch. The overhang is the projection beyond the wall, and the eave and ridge are edges of the roof plane rather than measures of steepness.

Question 45Structural Systems and Foundations

Which foundation type is most appropriate where a house must bear on soil that is weak near the surface but firm at depth?

  1. A deep foundation using driven piles or drilled piers Correct answer.
  2. A rubble trench perimeter drain
  3. A shallow spread footing at frost depth
  4. A slab-on-grade with thickened edges

Explanation

Deep foundations bypass unsuitable near-surface soils and transfer load to a competent stratum or to friction along the shaft. Shallow footings and slabs depend on adequate bearing close to grade. A rubble drain addresses water, not bearing capacity.

Question 46Structural Systems and Foundations

What is the function of a header over a window opening in a bearing wall?

  1. To provide a stop for the window sash
  2. To carry loads around the opening to adjacent framing Correct answer.
  3. To trim the rough opening to the window size
  4. To conceal the flashing above the window

Explanation

Removing wall framing at an opening interrupts the load path, so a header spans the gap and delivers the loads to jack studs on each side. Trimming, sash stops, and flashing are unrelated functions. The header is a structural beam within the wall.

Question 47Structural Systems and Foundations

Which statement correctly describes a load-bearing wall?

  1. It exists only in buildings with steel frames
  2. It carries loads from above in addition to its own weight Correct answer.
  3. It is always located on the building's exterior
  4. It resists only wind pressure on the building envelope

Explanation

A bearing wall transmits roof, floor, or wall loads from above down to the structure below, in addition to supporting itself. Nonbearing walls carry only their own weight and lateral pressures. Bearing walls may be interior or exterior and occur in any framing material.

Question 48Structural Systems and Foundations

Which condition most commonly causes differential settlement of a house foundation?

  1. Excessive attic ventilation
  2. A roof covering heavier than the design load
  3. Variation in soil type or moisture beneath the footing Correct answer.
  4. Uniform soil of consistent bearing capacity

Explanation

Differential settlement occurs when one part of the foundation bears on firmer or drier soil than another, so the two areas move by different amounts. Uniform conditions tend to produce uniform movement. Roof weight and attic ventilation do not create uneven soil response.

Question 49Structural Systems and Foundations

A two-story wood-frame house has a 20-foot clear span across its basement. Which framing approach is structurally appropriate for supporting the floor above?

  1. A built-up beam at midspan supported by steel or wood columns Correct answer.
  2. A single 2x8 joist spanning the full 20 feet
  3. A layer of plywood subfloor laid directly on the slab
  4. A row of nonbearing partition walls on the slab

Explanation

A 20-foot clear span exceeds the practical capacity of ordinary dimension lumber joists, so a midspan beam carried on columns shortens the joist span. The beam then delivers load to footings under each column. Subfloor alone and nonbearing partitions cannot carry the floor loads.

Question 50Structural Systems and Foundations

A concrete foundation wall shows a horizontal crack about mid-height on the exterior face. Which cause is most consistent with this pattern?

  1. Settlement of one corner of the footing
  2. Lateral earth pressure and backfill loading Correct answer.
  3. Uplift from wind on the roof
  4. Shrinkage of the roof sheathing

Explanation

Horizontal cracking near mid-height of a basement wall typically reflects bending from lateral soil and backfill pressure pushing inward. Corner settlement usually produces diagonal or stair-step cracking near the corner. Roof-related movement affects the top of the structure, not mid-wall.