PDD ARE 5.0 Project Development and Documentation Exam Questions and Answers

Glass-fiber-reinforced concrete (GFRC) panels offer several advantages compared to architectural precast concrete panels:

GFRC panels are lighter due to their thin profile and use of fiber reinforcement, reducing structural load and facilitating installation.

Precast concrete panels are heavier and thicker.

Strength of GFRC is adequate but typically not higher than traditional precast.

Quality control and fabrication time are comparable or vary depending on the project and fabrication process.

Therefore, the significant advantage is decreased weight.

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).

1. Problem Summary

Goal: Reduce reverberation time (RT) in the Tap Room to 2.0 seconds or less.

Current design: 2' x 2' acoustic ceiling tile system (RT = 2.0 seconds) installed above fans.

Constraint: Minimize additional project cost.

Recommendation from acoustical engineer: Use materials to achieve target RT without redesigning the space.

2. Review of Table Data

Material

RT

SF

SF Cost

Cementitious Wood Fiber Panels (1")

2.0

448

$12.64

Cementitious Wood Fiber Panels (2")

1.8

384

$18.95

2x2 Acoustical Ceiling Tile (15/16")

2.0

900

$8.81

Acoustical Sound Board (1")

1.6

256

$18.23

3. Interpretation of RT Values

Current 2x2 Acoustic Ceiling Tile: RT = 2.0 seconds → meets the target exactly.

However, fans may reduce the acoustic performance by reflecting or scattering sound, so supplemental absorption may be needed.

Adding Acoustical Sound Board (RT = 1.6) above the existing tile system will improve absorption and lower RT below 2.0 seconds.

4. Cost & Constructability

Retaining the current ceiling layout and simply adding a layer above is:

Least disruptive to current design.

Avoids redesign of the ceiling cloud layout.

Minimizes schedule impact (critical for design-build with compressed schedule).

Replacing with wood fiber panels (1" or 2") would require removal of existing tile, redesign of suspension, and higher cost/SF.

5. Why Other Options Are Incorrect

A. Remove fans: This addresses air movement, not RT. Removing them does not guarantee RT improvement and conflicts with HVAC design intent.

B. One cloud + 1" wood fiber panels: Reduces coverage area and may not meet RT goal; also costly and disruptive.

C. One cloud + 2" wood fiber panels: Even more costly, same redesign problem as B.

D. Retain tiles and add sound board above: Achieves RT < 2.0, minimal disruption, cost-effective vs. full replacement → best option.

6. NCARB ARE 5.0 PDD Study Guide References

Content Area: Building Systems Integration — Acoustics

Reference Sources:

Architectural Graphic Standards — Acoustic material properties

Mechanical and Electrical Equipment for Buildings (MEEB) — Room acoustics and reverberation control

ASTM C423 — Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method

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.

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).

Hardware Set 3.0 includes: three full-mortise hinges, an entrance/privacy lock, matching core, wall stop, silencers, and a coat hook. That combination is the typical specification for a single-occupant toilet room or similar private room opening off a corridor—privacy latch (not an exit device), door control, and a coat hook inside. Sets 1.0 and 4.0 are push/pull or exit-device packages (for egress/assembly or non-latching doors), and Set 2.0 is a basic push-pull set without a latch—none of which meet the corridor toilet-room function.

PDD refs: Division 08 door hardware scheduling; coordination of door sets with room function and code egress/privacy requirements.

Elevations (A-03): material callouts, notes, and textures for every façade.

Wall sections (A-06): assembly build-ups change (continuous insulation, drainage plane, WRB, attachment to PEMB girts, control joints, weeps, and terminations).

Details (A-07): heads/sills/jambs, base of wall/grade, parapet, expansion and control joints, and transition flashing details must be revised for EIFS.

Sheets like A-00 (cover) or A-02 (plans) generally don’t carry the envelope system specifics and would not need detail changes for a cladding swap.

PDD refs: Drawings coordination—plans vs. elevations vs. sections/details; Division 07 EIFS system requirements; PEMB cladding interfaces.

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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.

When metals are embedded in concrete or masonry, corrosion resistance is a critical factor due to the alkaline environment and potential moisture exposure.

Stainless steel has excellent corrosion resistance, making it ideal for embedments in concrete or masonry where long-term durability is required.

Bronze is corrosion-resistant but typically used for decorative or hardware applications, not structural embedments.

Aluminum corrodes readily in alkaline concrete environments and is not suitable for embedments without protective coatings.

Cast iron is susceptible to rust and corrosion in moist conditions and is generally avoided for embedded components.

Thus, stainless steel is best suited for durability and corrosion resistance in concrete/masonry embedments.

Understanding the Problem

The question addresses parapet coping design in a wet climate with a focus on:

Minimizing maintenance

Preventing water from running down the face of the wall

Parapet copings protect the top of the parapet wall from water penetration and are designed to shed water away from the wall below.

Analysis of the Options

A. Flat Coping

A flat coping (Option A) has no slope and allows water to pool on the surface.

This pooling increases the likelihood of infiltration and material deterioration over time.

In wet climates, this is poor practice because standing water leads to freeze-thaw damage, staining, and faster degradation.

Maintenance needs are higher.

B. Single-Slope Coping

This coping (Option B) has a slope toward one side, which improves drainage.

However, if sloped toward the inside of the parapet, it increases roof drainage load and risk of water penetration at roof/wall junction.

If sloped toward the outside, water can run down the wall face, which the client specifically wants to avoid.

This design might also stain exterior wall finishes over time.

C. Double-Slope (Pitched) Coping with Drip Edges

This coping (Option C) is pitched toward both sides, with drip edges to break water runoff before it reaches the wall face.

Water is shed away efficiently, and drip grooves prevent capillary action that would pull water back toward the wall.

This is best practice in wet climates and greatly reduces maintenance by preventing staining and wall saturation.

Recommended by NRCA (National Roofing Contractors Association) and referenced in Architectural Graphic Standards for parapet detailing.

NCARB ARE 5.0 PDD Reference:

Content Area: Integration of Building Materials & Systems — Building Envelope Detailing

Source Materials:

Architectural Graphic Standards — Parapet Cap/Coping Details

Building Construction Illustrated by Francis D.K. Ching — Water Management & Flashing

NRCA Roofing Manual — Best Practices for Roof Edge & Parapet Design

Key Principle: Parapet copings in wet climates should always slope to shed water away, incorporate overhangs with drips, and prevent water from cascading down the building face.

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

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

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.

The diagram shows a displacement ventilation system. In this system:

Cool supply air (about 65°F) is introduced at floor level at low velocity through floor diffusers.

Warm air rises as it picks up heat from occupants/equipment and stratifies near the ceiling, where it is returned or exhausted.

This creates a stratification layer with cooler, cleaner air in the occupied zone and warmer air above.

This is efficient for comfort, air quality, and energy use in spaces ≤12 ft high.

Why not other options:

A: This system uses a plenum return, not ducted supply and return for both.

C: It is efficient in summer since it uses warmer supply air and reduced fan energy.

D: Individual comfort control is possible via diffuser location/adjustment.

PDD Reference: ARE 5.0 PDD “Mechanical Systems—Air distribution types,” ASHRAE Fundamentals, displacement ventilation diagrams.

When new plan‐review rules require 1-hour fire-resistance for storage rooms >150 sf, the least cost/time/program impact is typically a 1-hour gypsum board assembly (metal studs with Type X on each side per UL/GA listings).

A. CMU: durable but higher material and labor cost; heavier, slower to install.

C/D. Splitting rooms: Avoids the rating but disrupts program, adds doors/partitions, circulation, and can increase costs and complexity.

PDD References: IBC Ch. 7 Fire & Smoke Protection Features; GA/UL fire‐rated wall assemblies; ARE 5.0 PDD—Code compliance strategies and cost/time implications of alternative assemblies.

Understanding the Problem

This question is about historic masonry restoration — specifically, repointing deteriorated mortar joints in soft-brick buildings.

Historic bricks, especially those made before the early 20th century, are often much softer and more porous than modern high-fired bricks. The mortar originally used was also softer, usually lime-based, which allowed for thermal movement, moisture permeability, and protection of the brick units.

Why the Correct Answer is “Duplication of Original Mortar Strength”

Best practice in preservation (as outlined in the Secretary of the Interior’s Standards for the Treatment of Historic Properties) is to match the original mortar in strength, composition, permeability, and appearance.

A mortar stronger than the original can cause the softer brick to crack or spall under thermal or moisture stresses, because the brick will end up being the weaker link and take the damage.

Duplication ensures that the new mortar works compatibly with the old masonry system — allowing for similar vapor transmission and structural flexibility.

Why the Other Options Are Incorrect:

B. Increased mortar strength over the original mortar — This is harmful in historic soft-brick construction. Stronger cement-based mortars can trap moisture in the brick, leading to freeze-thaw damage and spalling.

C. A bond stronger than the brick — This would cause the brick to fail first when stress occurs, which is undesirable in preservation work.

D. Deeper joint profiles — Deeply raking out joints unnecessarily can damage surrounding brick edges and change the visual proportions; repointing depth should only be enough to remove deteriorated mortar (typically 2–2.5 times the joint width).

NCARB ARE 5.0 PDD Study Guide References:

Content Area: Integration of Building Materials & Systems — Historic Preservation Techniques

Key Resources:

The Secretary of the Interior’s Standards for Rehabilitation & Illustrated Guidelines for Rehabilitating Historic Buildings

National Park Service Preservation Brief 2: “Repointing Mortar Joints in Historic Masonry Buildings”

Building Construction Illustrated — Masonry Restoration

Key Preservation Principle: “New mortar should match the historic mortar in composition, strength, and vapor permeability.”

Shop drawings show how components are to be fabricated or installed by the contractor. They do not redefine the design intent but elaborate on it. Refer to Objective 3.4: Evaluate submittals.

(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

1. Reviewing the Construction Estimate

The listed components are:

Architectural Precast Panels — exterior cladding

Aluminum Storefront Windows — glazing system

Prefinished Metal Sill Flashing — weatherproofing at sill

Sealant — for joints between components

No line item appears for thermal insulation.

2. Identifying the Missing Element in the Axonometric Detail

Looking at the drawing:

The detail shows precast concrete panel cladding outside.

A storefront frame and glazing in the opening.

There is a hatched layer behind the precast in the stud cavity area — this represents continuous insulation.

The insulation is a required component for the wall to meet energy code R-value/U-factor requirements (per IECC or ASHRAE 90.1).

3. Why This is Critical

Insulation is essential for thermal performance, occupant comfort, and energy efficiency.

Omitting it from the estimate could cause:

Noncompliance with code.

Incomplete cost budgeting.

Change orders during construction.

In ARE 5.0 PDD, architects must check that all components of an assembly are represented in the cost estimate.

4. References

NCARB ARE 5.0 Handbook — PDD Content Area 3: Integration of Building Materials & Systems

Architectural Graphic Standards — Precast wall sections with insulation

Building Construction Illustrated (Ching) — Continuous insulation in wall assemblies

Energy Code References: IECC Table C402.1.3 for minimum continuous insulation requirements in exterior walls

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.

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.

(PDD) Study Guide References

For historic masonry rehabilitation, the accepted approach (e.g., NPS Preservation Brief 2: Repointing Mortar Joints in Historic Masonry) is to hand‑rake deteriorated mortar to a proper depth (typically 2–2½× the joint width or until sound mortar is reached), avoid power‑saw removal that can damage historic brick, and match the original mortar in composition, hardness, color, and tooling.

A is incorrect because removing all mortar for a “uniform appearance” is unnecessary and risks damaging sound joints.

B is incorrect because electric saws can chip and over‑cut historic brick arrises, violating preservation best practices.

C is correct: careful hand removal of loose/deteriorated mortar followed by repointing with compatible mortar is the recommended method.

PDD References: Historic fabric protection under “Codes/Regulations & Standards—Historic preservation,” detailing of masonry repairs in construction documents (Division 04), and QA/QC specifications for repointing.

1. Understanding the APA Grade Stamp

The stamp in the exhibit reads:

APA RATED SHEATHING 32/16

15/32 INCH (thickness)

SIZED FOR SPACING

EXPOSURE 1 (can handle temporary moisture exposure)

2. Meaning of "32/16"

The numbers 32/16 are the span ratings for the panel:

32 inches = maximum recommended span for roof sheathing (when applied perpendicular to supports).

16 inches = maximum recommended span for floor sheathing (when applied perpendicular to supports).

These ratings are established by APA (The Engineered Wood Association) based on panel thickness, grade, and allowable loads/deflection limits.

3. Applying to the Question

The question asks specifically for maximum recommended span for use in a floor system.

From the stamp:

Floor span rating = 16 inches

Therefore, the correct answer is 16 in.

4. Why Other Options Are Incorrect:

A. 15 in — Not the value given; 16 in is the rating.

C. 32 in — This is for roof applications, not floor systems.

D. 108 in — Not related to APA span ratings; possibly confused with the certification number "NBR-108."

5. NCARB ARE 5.0 PDD Study Guide References:

Content Area: Building Materials & Assemblies — Wood Products

Reference Sources:

APA – The Engineered Wood Association: Panel Span Ratings Guide

Building Construction Illustrated (Ching) — Plywood and OSB Panel Markings

IBC Chapter 23 — Wood span and application requirements

Where no public sewer is available, on-site wastewater treatment (septic tank + leach field) is required. This supports Objective 3.2, considering utility systems and site limitations.

Converting two existing 2-bedroom units into two 1-bedroom units each yields two additional dwelling units total, while keeping every unit on an exterior wall for light/vent and maintaining typical plumbing stacks/egress.

A introduces two studios (size/layout risk) and alters a lower-floor stack; more coordination risk.

C converts a Laundry (likely interior and serving the building) into a unit—problematic for light/ventilation and building services.

PDD refs: IBC R-2 unit planning, light/ventilation, egress; planning & stacking strategies to minimize rework.

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 diagrams depict metal stud or curtain wall connections to structural frames under wind loading. Diagonal bracing can be eliminated when the connection itself provides lateral restraint in both directions.

A: Shows a connection with angles or plates attached to resist both in-plane and out-of-plane forces, creating a moment-resisting connection that can handle wind loads without diagonal bracing.

B, C, D: These connections allow slip or have limited fixity—requiring separate bracing to resist lateral loads.

PDD Reference: ARE 5.0 PDD “Structural Systems—Lateral load resistance in curtain wall and stud framing connections”; AISC Steel Design Guide for cladding attachment; Curtain wall engineering details.