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.

In a tropical climate, the interior is cooler and drier than the hot, humid exterior. The vapor drive is

from outside → inside, so the vapor retarder must be installed on the warm/moist side of the

assembly, which is below the insulation when the insulation is above the roof deck. This prevents

moist exterior air from reaching cooler surfaces inside the insulation where condensation could

occur.

PDD Reference: Psychrometrics & vapor drive principles, PDD “Thermal & Moisture Protection—

Placement of vapor barriers,” ASHRAE Handbook recommendations.

Comprehensive Detailed Explanation with all NCARB ARE 5.0 Project Development and

Documentation (PDD) Study Guide Reference:

The question is about the relative section modulus (S) required for a glue-laminated beam vs. a sawn

timber beam to resist the same bending moment. The formula relating bending stress (Fb), moment

(M), and section modulus (S) is:

https://kxbjsyuhceggsyvxdkof.supabase.co/storage/v1/object/public/file-images/NCARB_PDD/page_7_img_1.jpg

For the same bending moment M, the section modulus is inversely proportional to the allowable

bending stress

https://kxbjsyuhceggsyvxdkof.supabase.co/storage/v1/object/public/file-images/NCARB_PDD/page_7_img_2.jpg

Therefore, the glue-laminated beam requires half the section modulus compared to the sawn timber

beam.

Supporting Reference:

NCARB ARE 5.0 Review Manual, Structural Systems chapter

Basic bending stress and beam design equations from structural design texts

Mortar joint finishes impact water resistance and weatherability:

Concave joint is the most weather-resistant. The joint is compressed and curved inward, forming a

dense, compact surface that sheds water effectively.

Weathered joint slopes outward but is less compact than concave.

Raked joint is recessed and can hold water, less weather-resistant.

Extruded joint protrudes and tends to trap water and dirt.

Therefore, concave joints provide the best weather protection.

Reference:

NCARB ARE 5.0 Review Manual, Materials and Assemblies chapter

Masonry construction standards and detailing guides

The energy code requirement R-13 + R-10 c.i. (continuous insulation) for above-grade walls

necessitates adding/confirming a thermal insulation section that covers both cavity insulation (R-13)

and continuous exterior insulation (R-10) (e.g., rigid boards, mineral wool boards). Section 072100—

Thermal Insulation is the correct overarching specification.

072119 Foamed-In-Place is a product-specific section and not required unless using SPF as the c.i.

075419 PVC is roofing.

PDD Reference: IECC/ASHRAE 90.1 envelope compliance; CSI Div. 07—Thermal Insulation (072100)

including rigid continuous insulation requirements

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.

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.

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 Reference:

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

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.

Reference:

NCARB ARE 5.0 Review Manual, Materials and Assemblies chapter

Building construction materials standards (ACI, ASTM) on metals in concrete

Corrosion resistance guides for metals embedded in concrete

(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 Reference:

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 Reference:

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