CHI Structural Systems Inspection 3 — Questions and Answers
Question 1: What is the purpose of a mudsill (sill plate) in residential construction?
- To anchor the wood framing to the concrete foundation (Correct answer)
- To provide a level surface for installing hardwood flooring
- To act as a moisture barrier between the concrete and framing
- To distribute roof loads across the top of the foundation wall
Correct answer: To anchor the wood framing to the concrete foundation
The mudsill is the lowest horizontal framing member that is bolted to the foundation, anchoring the wood structure to the concrete or masonry.
Question 2: An inspector observes stair-step cracking in a brick veneer wall. What does this pattern most likely indicate?
- Differential foundation settlement causing movement in the masonry (Correct answer)
- Normal thermal expansion of the brick veneer
- Freeze-thaw damage to the mortar joints only
- Improper brick veneer tie spacing during original construction
Correct answer: Differential foundation settlement causing movement in the masonry
Stair-step cracking in brick veneer typically follows mortar joints diagonally and is a classic sign of differential settlement in the foundation.
Question 3: What is a cripple wall in residential construction, and why is it structurally significant?
- A short stud wall between the foundation and first floor that can be vulnerable to racking during earthquakes (Correct answer)
- A wall framed with undersized studs due to a construction error
- Any wall with openings that interrupt the full-height stud layout
- A retaining wall that supports the weight of the chimney
Correct answer: A short stud wall between the foundation and first floor that can be vulnerable to racking during earthquakes
Cripple walls are short wood-framed walls between the foundation and first floor that are especially vulnerable to lateral racking forces during seismic events.
Question 4: When inspecting a crawl space, the inspector notices that wood posts supporting a beam are sitting directly on the dirt floor without footings. What is the primary concern?
- The posts can sink or shift due to soil movement and moisture, compromising structural support (Correct answer)
- Dirt contact is only a concern for steel posts, not wood posts
- Posts without footings are acceptable if the soil is undisturbed native soil
- The concern is limited to wood decay in wet climates
Correct answer: The posts can sink or shift due to soil movement and moisture, compromising structural support
Posts without proper footings have no stable bearing surface, and the wood is subject to decay and insect damage from direct soil contact.
Question 5: What does an inspector look for when examining roof trusses for structural integrity?
- Broken or missing connector plates, cracked members, and unauthorized cuts or notches (Correct answer)
- The thickness of insulation covering the trusses in conditioned spaces
- Whether the truss manufacturer label is still visible on each truss
- The color uniformity of the wood indicating consistent moisture content
Correct answer: Broken or missing connector plates, cracked members, and unauthorized cuts or notches
Structural truss deficiencies include damaged gang-nail connector plates, cracked or broken chords, and field modifications that compromise the engineered design.
Question 6: A home inspector finds that a load-bearing wall has been partially removed without a header installed above the opening. What is the primary structural risk?
- The floor or roof structure above may deflect excessively or collapse due to lack of load transfer (Correct answer)
- The opening will allow drafts that increase heating and cooling costs
- The risk is limited to the wall's drywall cracking from vibration
- Only load-bearing walls with plumbing inside require headers
Correct answer: The floor or roof structure above may deflect excessively or collapse due to lack of load transfer
Without a properly sized header, loads from above have no structural path to the adjacent wall framing, causing deflection or potential structural failure.
Question 7: Which observation during a foundation inspection would MOST concern a home inspector regarding soil-related movement?
- Diagonal cracks radiating from corners of window and door openings in the foundation (Correct answer)
- Hairline vertical cracks less than 1/16 inch wide uniformly spaced along the wall
- Efflorescence (white mineral deposits) on the interior face of the foundation
- A small amount of dampness on the exterior face of the foundation wall after rain
Correct answer: Diagonal cracks radiating from corners of window and door openings in the foundation
Diagonal cracks at window and door openings typically indicate differential settlement, where the soil is supporting the foundation unevenly.
CHI Structural Systems Inspection 3
What is the purpose of a mudsill (sill plate) in residential construction?