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Board‑and‑batten is a vertical siding system: wide vertical boards with narrow battens covering the joints; its detailing, drainage, and expansion behavior are intended for vertical application only.

By contrast, plain bevel (lap) siding is typically horizontal; V‑shiplap and V‑groove T&G can be detailed either direction depending on manufacturer, but are commonly horizontal on walls.

PDD References: Exterior wall cladding and detailing under “Materials & Assemblies—Exterior enclosure,” CSI Div. 06 & 07 application details.

Understanding the Diagram

The diagram shows a 480Y/277V three-phase, four-wire wye-connected system with a neutral (N) and system ground.

480 V = Voltage between any two phase conductors (line-to-line)

277 V = Voltage between any one phase conductor and neutral (line-to-neutral)

Fluorescent Lighting Voltage Requirements

Standard commercial fluorescent lighting systems are typically designed for 277 V operation in the U.S. (in buildings with a 480Y/277V system).

To achieve 277 V, you connect one phase conductor (A, B, or C) to Neutral (N).

This is a single-phase line-to-neutral connection.

Which Conductors to Use?

In the given options, the correct pair must give 277 V.

C, N → 277 V line-to-neutral → Correct for fluorescent lighting.

Other options produce different results:

A, B = 480 V (line-to-line) — too high for fluorescent ballasts.

C, A, B = all three phases — used for three-phase loads, not lighting.

C, A, N — would give two circuits, but includes extra phase unnecessarily for single-phase lighting.

NCARB ARE 5.0 PDD Study Guide References:

Content Area: Electrical Systems — Power Distribution and Circuiting for Lighting

Source References:

Electrical Systems for Architects — Fluorescent lighting voltage selection

MEEB (Mechanical and Electrical Equipment for Buildings) — Chapter on Electrical Service and Lighting Systems

NEC (National Electrical Code) — Voltage to ground for wye-connected systems

Key Point:

For a 480Y/277V wye system, fluorescent lighting should be connected from any phase to neutral for 277 V operation.

Understanding Slip Matching in Wood Veneer

When wood veneer is sliced from a log, each sheet (or "leaf") has a repeating grain pattern. How those sheets are arranged side-by-side on a panel is called the matching method.

Slip Matching:

Consecutive leaves are laid side-by-side without flipping or reversing them.

This creates a repeating grain pattern that flows consistently across the panel.

The result is a uniform, continuous grain with no "mirror image" effect — the cathedrals and figure in the grain run in the same direction from sheet to sheet.

Slip matching often produces a striped effect if the grain is straight, or a flowing, consistent repeat if the grain is more figured.

Identifying Slip Matching in the Exhibit:

Option A shows consecutive veneer leaves with the grain pattern running in the same orientation across the panel — no mirroring, only repetition. This is classic slip match.

Option B shows book matching — where every other leaf is flipped horizontally to create a mirrored grain pattern.

Option C appears to be random matching — leaves are placed without grain sequence alignment.

Option D shows reverse slip matching — similar to slip match but alternating leaves are reversed end-to-end.

NCARB ARE 5.0 PDD Study Guide References:

Content Area: Integration of Materials & Finishes — Millwork and Casework Veneer Matching Methods

Sources:

Architectural Woodwork Standards (AWS) — Section on Veneer Matching

Architectural Graphic Standards — Finish Carpentry and Veneer Matching

Building Construction Illustrated (Ching) — Interior Finish Carpentry

Key Point:

Slip matching keeps all veneer leaves in the same orientation, producing a consistent flow of the grain without the mirrored effect seen in book matching.

Cutting holes in beam webs is common for running mechanical, electrical, or plumbing services but must be done carefully to avoid weakening structural integrity.

Holes should be located near mid-span supports (points of low bending moment and high shear) to reduce impact on beam bending strength.

Holes should not be located near areas of maximum bending moment (typically mid-span between supports), because this is where the beam experiences maximum tension or compression.

Locations 2 and 4 are at or near the beam supports (shear zones), and generally small holes can be cut there, following size limits and reinforcement guidelines.

Locations 1, 3, and 5 are closer to mid-span or areas of high bending stress, so holes here risk compromising the beam’s moment capacity.

Per IBC Chapter 6 and Chapter 7, distillation involving flammable liquids requires a 2-hour fire-resistance-rated fire wall between H-occupancy (hazardous) and assembly use (A-2). Objective 1.3 of the PDD Handbook emphasizes understanding of life safety code implications in space planning.

Poplar is a hardwood that is relatively inexpensive compared to species like maple, cherry, or oak. It has:

Good hardness and uniform grain

Takes paint and stain well (although stain may require pre-treatment for even color)

Often used as a cost-effective substitute for higher-priced hardwoods in furniture, millwork, and trim.

Why not others:

Red oak: Hard and attractive but more costly.

Cypress: Softwood valued for decay resistance, not typically a hardwood substitute.

Redwood: Softwood, expensive, used for exterior decay resistance.

PDD Reference: ARE 5.0 PDD “Materials—Wood species characteristics,” CSI Div. 06 Wood & Plastics, Architectural Woodwork Institute (AWI) standards.

The diagram shows a basement foundation wall below the water table. During heavy rains, the water table can rise, increasing hydrostatic pressure against foundation walls and under the slab.

Key concern:

While lateral water pressure against the walls is a factor, the question specifies "also a major concern". In this scenario, the water pressure beneath the slab can cause buoyant uplift — vertical upward pressure — known as hydrostatic uplift or floatation.

If this upward force exceeds the weight of the slab and the structure above, it can cause the slab to crack, lift, or fail — especially if there is no adequate under-slab drainage or tiedown anchors.

Why not the other options:

A. Moisture absorption of the concrete foundation wall — Concrete is porous, but waterproofing and drainage address this; not as critical in terms of structural threat as uplift.

B. Increased weight on the footings — Hydrostatic pressure acts laterally and upward; it does not significantly increase vertical load on footings in the same way dead load does.

D. Differential lateral pressure on total building structure — Lateral pressure affects the foundation walls, but "total building structure" is less directly impacted than the immediate risk to the slab from uplift.

NCARB PDD References:

ARE 5.0 Handbook — PDD Section: Site conditions and foundation systems

IBC 2018 Section 1805.4 — Waterproofing and drainage

Foundation Engineering principles — Hydrostatic uplift and buoyancy

NCARB PDD Study Guide Topic: Subsurface water control (sumps, drain tiles, hydrostatic relief)

Designing a barrier-free (accessible) building entrance requires coordination among:

Door schedule: Door sizes, types, clearances, and thresholds

Hardware schedule: Handles, closers, locks, and accessibility hardware (e.g., lever handles, automatic operators)

Alarm system design: To ensure audible and visual alarms meet ADA requirements for people with disabilities, particularly for emergency egress

Other documents like electrical and structural plans are important but less directly related to barrier-free entrance compliance.

Purpose of the Air Space in Brick Veneer Walls

In a typical brick veneer cavity wall assembly, there is an air space between the back side of the brick and the sheathing (or water-resistive barrier) of the structural wall. This space is typically 1 to 2 inches wide and serves several critical functions:

Moisture Drainage and Ventilation

Rainwater can penetrate brick veneer through joints and cracks.

The air cavity allows water to drain down the back of the veneer to flashing and out through weep holes.

It also provides ventilation to help dry out the wall assembly.

Minimizing Mortar Bridging

During construction, mortar can drop down into the cavity from bricklaying.

If mortar bridges across to the sheathing, it can create a path for moisture to move into the structure.

The 2-inch cavity helps reduce the chance that mortar droppings will fully bridge the gap, ensuring the drainage plane stays functional.

Why Other Options Are Incorrect:

A. To meet the minimum R-value — The air space in brick veneer is not designed as insulation; its thermal benefit is minimal compared to continuous insulation layers.

B. Allow for differential movement — Brick veneer differential movement is accommodated by wall ties and control joints, not by the air cavity.

C. Provide space for roof drain piping — Roof drainage piping is routed separately and is not part of the brick veneer cavity design.

NCARB ARE 5.0 PDD Study Guide References:

Content Area: Building Envelope Systems — Masonry Wall Assemblies

Source References:

Building Construction Illustrated (Ching) — Brick Veneer Wall Sections and Cavity Function

Architectural Graphic Standards — Masonry Veneer Construction Details

BIA (Brick Industry Association) Technical Notes 21 & 21A — Cavity Wall Design and Construction

Key Principle:

A 2-inch air cavity behind brick veneer is primarily to ensure proper drainage and to minimize mortar bridging, which would otherwise allow moisture intrusion into the building.

When a GMP (Guaranteed Maximum Price) is established before the design is 100% complete and specific materials are not yet chosen, the correct approach is to specify allowances in the project manual.

An allowance is a fixed monetary amount for a specific scope item (e.g., flooring finishes) that allows the contractor to carry a cost in the bid/GMP until the actual product is selected. This ensures the GMP covers the item without delaying pricing.

A. Contingency — Is for unforeseen conditions, not specific unselected finishes.

B. Schedule of unit prices — Typically used for variable-quantity work, not for unknown product selection.

D. Alternate — Provides an option for substitution, but does not guarantee a base cost in the GMP.

PDD Reference: ARE 5.0 PDD “Project Manual and Specifications—Allowances, Alternates, and Unit Prices,” AIA A201 §3.8, CSI Division 01—General Requirements.

In the provided pressure-plate curtain wall mullion detail, the thermal break is typically located between the interior and exterior aluminum components of the mullion to prevent conductive heat transfer.

✅ Thermal Break Location:

Look for the black or dark shaded strip in the middle of the mullion where the two separate metal parts meet — this strip is a non-metallic insulating material (usually polyamide or other plastic) that interrupts the metal-to-metal connection between interior and exterior.

In this image, the thermal break is located:

➡️ In the vertical center of the mullion, between the inner and outer aluminum extrusions, where a black isolator or separator is shown (just above and below the screw/fastener).

Clicking on this narrow dark band (thermal isolator) between the inner and outer components of the curtain wall mullion would be the correct hotspot answer.

The arrow in the wall-floor assembly indicates a horizontal structural member attached to a wall, used to support the end of a floor joist. This is called a ledger.

Ledger: Typically a dimensional lumber or engineered wood member fastened to a wall that supports floor framing members (joists).

Fire block: Installed to limit fire spread in concealed spaces—often mid-wall or mid-stud cavity, not in this floor-to-wall position.

Girt: A horizontal framing member in a wall, usually in steel-frame or post-frame construction, not in conventional wood framing for floors.

Lateral shear plate: A metal plate for shear transfer, not applicable here.

PDD References:

ARE 5.0 PDD “Structural Systems—Wood framing details”

IBC §2308.4—Floor framing requirements

AWC (American Wood Council) “Wood Frame Construction Manual” Ledger attachment details

With outdoor below freezing and indoor RH ~40% continuously, interior vapor will migrate outward. If a proper interior-side vapor barrier/retarder is missing, moisture moves through the wall and can condense and freeze at the cold exterior stone, forming visible ice. Insulation, air spaces, or rain screens help heat/moisture management, but the symptom (ice due to vapor diffusion) points specifically to the lack of an interior vapor barrier in a cold-climate assembly.

PDD references: Moisture control & vapor retarder strategy in cold climates; condensation diagnostics (ASHRAE Fundamentals; ARE 5.0 PDD—Envelope moisture control).

Understanding the Diagram

The detail shows a fan coil unit suspended from the structure, with:

Vibration isolators at the hanging rods to limit mechanical vibration transfer to the structure.

Flexible duct connections between the fan coil unit and the rigid ductwork.

Purpose of Flexible Duct Connections

Flexible connections in HVAC duct systems are designed to:

Prevent transmission of vibration and sound from the mechanical equipment (fan coil unit) into the rigid ductwork and building.

Compensate for small misalignments between the ductwork and equipment.

Accommodate minor thermal expansion/contraction movements.

Key Function in This Context:

Fan coil units contain fans that create vibration and noise. Without a flexible connection, this vibration would travel directly through the rigid ductwork into occupied spaces, increasing noise levels.

Why Other Options Are Incorrect:

A. To provide a field point of connection — While the flexible connector does connect ducts, its purpose is not just convenience; it is specifically for vibration/sound isolation.

B. To insulate against heat transfer — This is done with thermal duct insulation, not flexible connectors.

D. To transition from flange to desired duct size — Transitions are made using sheet metal fittings, not flexible connectors.

NCARB ARE 5.0 PDD Study Guide References:

Content Area: Integration of Building Materials & Systems — Mechanical Systems and Acoustics

Sources:

Mechanical and Electrical Equipment for Buildings (MEEB) — Vibration Control in Mechanical Systems

Architectural Graphic Standards — Flexible Duct Connections for Noise and Vibration Isolation

ASHRAE Handbook — HVAC Applications, Chapter on Sound and Vibration Control

Key Point:

Flexible connectors in ductwork break the direct mechanical path for vibration and sound, reducing noise transfer from fans to occupied areas.

Step-by-Step Reasoning

1. Mezzanine Area Limitations — IBC Section 505.2.1

From the exhibit:

The aggregate area of a mezzanine within a room shall be not greater than one-third of the floor area of that room/space.

Given:

Main floor = 9,000 SF

Maximum mezzanine size = 1/3 × 9,000 SF = 3,000 SF

2. Openness Requirements — IBC Section 505.2.3

From the exhibit:

A mezzanine must be open to the room below unless it qualifies for one of the listed exceptions.

3. Relevant Exception for Enclosed Mezzanine

Exception 1:

Mezzanines (or portions thereof) are not required to be open to the room if the occupant load of the enclosed space is not greater than 10.

Exception 3:

Mezzanines (or portions thereof) are not required to be open to the room if the aggregate floor area of the enclosed space is ≤ 10% of the mezzanine area.

However — the scenario says:

The mezzanine will have one exit (so it’s not an open floor requiring multiple exits)

The architect notes there are adequate exits on the main floor to handle additional occupant load from the mezzanine → This means it could be enclosed if allowed by exceptions.

4. Evaluate Each Option:

A. 2,500 SF open lounge for 20 people

Size < 3,000 SF → OK on area.

Open mezzanine → Complies without needing an exception.

But 20 occupants means more than 10 occupant load, so it can’t be enclosed unless open — this one is already open, so fine.

This works, but the question asks for which method should the architect design, and the key is the one-exit enclosed scenario.

B. 2,750 SF enclosed business center for 15 people

Size < 3,000 SF → OK.

It is enclosed, and occupant load is 15, which is greater than 10. That means Exception 1 doesn’t apply.

But Exception 3 says: enclosed space can be allowed if enclosed area ≤ 10% of mezzanine area. Here:

10% of 2,750 SF = 275 SF.

If the enclosed portion is the business center itself (full area enclosed), then it fails Exception 3.

Wait: This would only be code-compliant as enclosed if the occupant load is ≤ 10 (Exception 1) OR enclosed area ≤ 10% of mezzanine (Exception 3).

This option might work only if the mezzanine is considered enclosed but the occupant load doesn’t require multiple exits and is allowed due to adequate exit capacity on the main floor — this appears to be the intended IBC Exception 1 scenario, but since OL = 15 > 10, it technically fails Exception 1.

The problem statement says “adequate exits available on main floor to pick up additional occupant load” — which would allow designing an enclosed mezzanine as long as total egress capacity is fine.

C. 3,250 SF open dining for 30 people

Size exceeds 3,000 SF → FAILS area limitation. Not allowed.

5. Conclusion

Given the constraints:

Must fit within 1/3 floor area rule (≤ 3,000 SF)

Must work with one exit and available exit capacity on main floor

Option C fails on size

Option A is possible but doesn’t use the enclosed condition in the prompt

Option B meets area limit, occupant load works with available exit capacity, and provides an enclosed use that matches the problem’s “program requirement” scenario

Glycol-cooled air conditioning systems use a glycol-water mixture as a secondary coolant instead of plain water. Glycol has lower freezing point and better heat transfer properties in certain conditions.

Advantages include:

Longer piping runs without freezing risk, allowing the chiller or cooling unit to be located further away from the computer room, useful for flexible building layouts.

Glycol prevents freezing in cold climates or exposed pipes.

It does not inherently reduce heat exhausted or is necessarily more sustainable than water cooling.

Glycol is generally more expensive than water.

Therefore, the primary advantage is the ability to locate the cooling unit farther from the space being cooled.

The detail shows a metal connector fastening a vertical framing member (stud or post) to a horizontal member (likely a top plate or beam). This type of metal connector—often a hurricane tie or hold-down—is designed to anchor the vertical framing to the horizontal framing to prevent separation caused by uplift forces.

Key points:

Uplift occurs when wind loads or seismic activity try to pull the roof or upper framing away from the wall below.

The connector wraps over and around members, securing them together.

Commonly used in roof-to-wall connections to comply with wind resistance requirements in the IBC and ASCE 7.

This does not primarily resist sliding (shear) or racking (lateral deformation of a frame), nor is it designed mainly for twisting (torsion).

PDD ARE Objective Tie-in:

ARE 5.0 PDD Objective 3.2 – Evaluate and integrate structural systems with architectural elements, ensuring proper load path continuity for resisting vertical and lateral loads, including uplift forces.

In subsurface drainage system design:

The shape, size, and slope of drainage lines are selected primarily to achieve a desired flow velocity that prevents sedimentation and clogging but does not cause erosion.

Minimizing or maximizing flow is not the goal; the system must convey the design flow efficiently.

Velocity must be balanced — too low leads to sediment build-up; too high causes pipe damage.

(Interior climate of the space, Exterior climate of the building location, Thermal resistance properties of the materials, Orientation of the building, Compatibility of the materials with adjacent materials)

Comprehensive Detailed Explanation with all NCARB ARE 5.0 Project Development and Documentation (PDD) Study Guide References:

Selecting thermal insulation and moisture control assemblies requires a holistic approach considering multiple factors:

A. Interior climate of the space: Critical to determine required insulation levels and vapor barrier placement.

B. Exterior climate: Determines heating or cooling loads, moisture conditions, freeze-thaw cycles.

D. Thermal resistance properties: R-value of materials is fundamental in controlling heat flow.

E. Orientation of the building: Affects solar heat gain, exposure to wind-driven rain, and thus moisture control strategy.

F. Compatibility of materials: Important to avoid chemical or physical degradation, ensure proper adhesion, and maintain performance over time.

C. Type of HVAC system is important for overall building performance but not a primary factor in selecting insulation and moisture control assemblies themselves, which are more dependent on physical and climatic factors.

Supporting References:

NCARB ARE 5.0 Review Manual, Environmental Systems and Materials chapters

ASHRAE Fundamentals Handbook (thermal insulation design)

Building Science Corporation’s guides on moisture control and thermal envelopes

In cold climates, the vapor drive is from the warm interior to the cold exterior during winter. The vapor retarder/barrier belongs on the warm-in-winter side of the assembly—i.e., behind the interior gypsum, before the framing/insulation—to prevent interior moisture from reaching cold layers where it could condense.

PDD references: Psychrometrics & vapor drive; vapor retarder placement (ASHRAE; IBC/IECC guidance; ARE 5.0 PDD—Thermal & Moisture Protection).

Control joints in concrete masonry walls are designed to accommodate movement caused by thermal expansion, moisture changes, and settlement.

Control joints should be placed at locations of stress concentration, such as changes in wall height, changes in wall thickness, or at large wall expanses.

They are not placed at the first course of masonry (which is typically reinforced and anchored to the foundation).

They are generally not placed at window corners or in the center of window openings but rather at planned intervals or changes in geometry.

Placing a control joint at changes in wall height allows movement without cracking.

When coordinating construction documents, heating duct clearances and tolerances in suspended ceiling plenum spaces must be verified with:

The mechanical engineer (for duct sizing and layout)

The ceiling manufacturer (to confirm the clearance requirements, installation tolerances, and compatibility with the ceiling system)

The ceiling manufacturer provides critical information on allowable spacing, panel sizes, suspension system limits, and any required clearances around ducts or pipes that run above the ceiling.

Other parties:

HVAC contractor executes installation but follows design and ceiling guidelines

Electrical contractor coordinates separate systems

Structural engineer focuses on load and framing, not ceiling duct clearance

Coordination is essential in PDD. When a clash arises, the architect must consult with the responsible consultant (plumbing engineer). This supports Objective 3.1: Coordinate consultant drawings.

IBC governs occupancy classification, occupant loads, and required means of egress. A 300-person taproom triggers egress path requirements under IBC Chapter 10. Objective 1.3 addresses code compliance.

Comprehensive Detailed Explanation with all NCARB ARE 5.0 Project Development and Documentation (PDD) Study Guide References

The project is rural with no public water or sewer; by context there is likely no city steam and possibly no natural gas main. New boilers therefore need a fuel source on site (commonly LP/propane or fuel oil), and the site plan should direct the GC to coordinate fuel storage tank location (clearances, protection, truck access, setbacks, fire code).

A presumes a gas utility service that may not exist.

B presumes a city steam utility (not present).

PDD Reference: Division 01 coordination notes; IMC/IFC for on-site fuel storage clearances and protection; site plan general notes best practices.

For light wood-frame buildings, the most economical way to develop lateral shear capacity—often without major structural alteration—is to add/upgrade wood structural panel (plywood/OSB) shear walls fastened to studs and plates per nailing schedules. This provides diaphragm and wall‐shear resistance with minimal added framing.

A. Moment connections in wood are labor-intensive and uncommon in light framing.

C. Horizontal board sheathing provides limited shear compared to plywood.

D. Gusset plates do not create a continuous shear diaphragm/wall.

PDD refs: AWC SDPWS (wood shear walls & diaphragms); ARE 5.0 PDD—Structural systems for lateral loads in light-frame construction; IBC Ch. 23.

1. Understanding the Diagram

The three sections in the exhibit show different curtain wall mullion profiles (vertical and horizontal sections) designed for glazing systems.

In curtain wall design, aluminum mullions must accommodate:

Structural loads (wind, dead load of glass, seismic)

Thermal expansion and contraction of metal members

Building movement (floor-to-floor deflection, live load, creep, seismic drift)

2. Why Vertical Expansion is Relevant

The vertical mullions in curtain wall systems span multiple floors and are typically anchored at one end and allowed to float/slip at the other end to accommodate vertical building movement.

Movement can be due to:

Thermal expansion of aluminum mullions (aluminum has a high coefficient of thermal expansion).

Inter-story drift from lateral loads.

Floor live-load deflection.

The mullion joinery and connections at the anchors are specifically detailed to allow vertical sliding while maintaining weather seals.

3. Why Other Options Are Incorrect

A. Capillary action — This refers to water movement in small spaces; curtain walls are designed with weeps and pressure-equalized cavities to prevent it, but that is not what the mullion’s slip connections are for.

B. Horizontal expansion — Horizontal movement is generally handled at horizontal mullions/transoms or gasket joints, not the vertical mullion extrusion as shown.

D. Surface tension — Refers to water behavior, not a structural or thermal movement design issue.

4. NCARB ARE 5.0 PDD Study Guide References

Content Area: Building Envelope Systems — Curtain Wall Detailing

Key Sources:

Architectural Graphic Standards — Curtain wall movement joints

Building Construction Illustrated (Ching) — Curtain wall expansion and anchoring details

AAMA (American Architectural Manufacturers Association) Curtain Wall Design Guide — Section on thermal movement and inter-story drift

The transformer is located in the first large box after the high-voltage primary feeders and before the secondary service conductors on the left side of the diagram.

Step-by-Step Reasoning

1. Understanding the diagram flow:

The leftmost symbol represents high-voltage primary feeders from the utility (2,400V, 4,160V, 7,200V, or 13,200V).

Immediately after that, there is a large box labeled "Secondary Service conductors" with standard building service voltages (120/208, 120/240, 277/480 V).

To get from primary (medium/high) voltage to these usable secondary voltages, you must step down the voltage — and that is done by a transformer.

2. Transformer location in electrical distribution:

Transformers are always placed between the incoming primary service and the secondary distribution system in building diagrams.

In this drawing, the transformer is symbolized by the first large square/rectangular box after the high-voltage primary feeders.

3. Why not any other box?

The following boxes and lines after this first step are feeders, panels, and motor starters — they operate at secondary voltage.

Only the transformer connects the utility high-voltage system to the building's lower-voltage system.

NCARB ARE 5.0 PDD References:

Content Area: Electrical Systems — Service Entrance and Distribution

Source References:

MEEB (Mechanical and Electrical Equipment for Buildings) — Chapter on Transformers & Electrical Service

NEC (National Electrical Code) Article 450 — Transformer Installation and Use

Architectural Graphic Standards — Single-Line Diagrams for Electrical Distribution

Key Point:

In building electrical distribution, the transformer is always between the high-voltage primary service and the secondary service conductors to step down voltage to a usable level for building loads.

Division 06 (Wood, Plastics, and Composites) of the Project Manual contains detailed specifications for finish carpentry and casework materials. This aligns with ARE Objective 2.1: Evaluate project manual sections for technical accuracy.