InterNACHI Structural Systems & Components 3

Question 1

What structural problem does 'sagging ridge line' most commonly indicate when observed from the exterior of a home?

Accepted Answer

Undersized rafters, missing collar ties, or inadequate ridge beam support

Answer

A sagging ridge line typically indicates undersized rafters, missing or failed collar ties, inadequate ridge support, or rafter spread causing the ridge to deflect downward.

Question 2

What is the term for the condition where floor joists bear on a foundation wall or beam at less than the minimum required distance?

Accepted Answer

Insufficient bearing

Answer

Insufficient bearing occurs when floor joists rest on a support surface with less than the code-required minimum contact length, typically 1.5 inches on wood and 3 inches on masonry.

Question 3

What does 'rafter spread' refer to in roof framing?

Accepted Answer

The outward movement of exterior walls caused by rafter thrust

Answer

Rafter spread is the outward horizontal force exerted by rafters on exterior walls, which can cause walls to bow outward if ceiling joists or collar ties don't resist this thrust.

Question 4

An inspector finds that a wood beam has a horizontal split running along its length. What type of defect is this?

Accepted Answer

Checking or splitting along the grain (seasoning crack)

Answer

Horizontal splits running along the grain are called checks or seasoning cracks, caused by wood drying unevenly; while typically cosmetic, deep checks in load-bearing members warrant further evaluation.

Question 5

Which foundation type is most susceptible to damage from expansive (clay) soils?

Accepted Answer

Shallow slab-on-grade foundations

Answer

Shallow slab-on-grade foundations are most vulnerable to expansive soils because clay soils swell when wet and shrink when dry, causing the slab to heave and crack.

(InterNACHI) International Association of Certified Home Inspectors Practice Test

(InterNACHI) International Association of Certified Home Inspectors Practice Test

InterNACHI Structural Systems & Components 3