ITAZ RQ: Structural

Question 1

Structural:

What is the difference between a strip footing and a pad footing and where would each be used?

Answer 1

• A strip footing or spread footing is used under a foundation wall. A pad footing is used under a column. Pad footings distribute concentrated loads. Strip footings handle more evenly distributed walls.

Question 2

Structural:

List 7 materials that a foundation might be made of.

Answer 2

• Concrete
• Concrete block
• Cinder block
• Brick
• Clay tile
• Stone
• Wood

Question 3

Structural:

What is the difference between a pilaster and a pier?

Answer 3

• A pilaster is a thickening of a foundation wall to accommodate the concentrated load of a beam or column.
• A pier is a stand alone structural member that can be thought of as a column stuck into the ground.

Question 4

Structural:

List four causes of cracks in foundation walls.

Answer 4

• Shrinkage
• Differential settling
• Heaving
• Horizontal forces

Question 5

Structural:

What is a shrinkage crack and what causes it?

Answer 5

• Shrinkage cracks are typically caused by natural curing of concrete.

Question 6

Structural:

What is a concentrated load?

Answer 6

• A point at which distributed weight is centralized upon. Loads from large areas are concentrated on a small point. This could be the end of a beam, bottom of a chimney or a column, for example.

Question 7

Structural:

What is ‘lateral support’ as it applies to foundations?

Answer 7

• Lateral support is usually a floor system secured to the top of a foundation wall, preventing it from tipping inward.

Question 8

Structural:

Why might a damaged foundation move suddenly after a heavy rain?

Answer 8

• Increase in hydrostatic pressure or swelling of expansive soils.

Question 9

Structural:

Floors will bend a little before they break. (True or False)

Answer 9

True

Question 10

Structural:

Why are rotted sills a problem?

Answer 10

• Rotted sills can be crushed and lead to differential settlement
• Rotted sills often mean rotted joists and studs
• Rotted sills means the house from is not well anchored to the foundation

Question 11

Structural:

List 12 common column problems.

Answer 11

• Missing
• Settled
• Crushed
• Leaning
• Buckled
• Rust
• Poorly secured at the top or bottom
• Mortar deterioration
• Spalling concrete or brick
• Mechanical damage
• Rot or insect damage
• Heaved

Question 12

Structural:

Which column materials are susceptible to crushing?

Answer 12

• Concrete

- Wood

Question 13

Structural:

How wide should the top of the column be, relative to the width of the beam above?

Answer 13

• The same width

Question 14

Structural:

List four types of engineered wood products used for beams.

Answer 14

• Glulams
• LVL- Laminated Vener Lumber
• LSL- Laminated Strand Lumber
• PSL- Parallel Strand Lumber

Question 15

Structural:

The ends of beams should have at least ____ inches of bearing on concrete or masonry and ____ inches on wood or metal?

Answer 15

• 3 inches, 1.5 inches

Question 16

Structural:

Wood beams should not be supported directly on hollow concrete block. (True or False)

Answer 16

• True

Question 17

Structural:

Describe the 1/3 rule of column stability using illustrations.

Answer 17

• Inner 1/3 area is acceptable. Anything outside of it is unstable.

Question 18

Structural:

List 6 materials that may be used for masonry walls.

Answer 18

• Brick
• Stone
• Concrete block
• Cinder block
• Clay tile
• Glass block

Question 19

Structural:

Missing fire stopping is more common on platform construction than balloon frame construction. (True or False)

Answer 19

• False

Question 20

Structural:

Brick veneer walls are watertight. (True or False)

Answer 20

• False

Question 21

Structural:

Rusting steel lintels over windows cause what kind of masonry crack patterns?

Answer 21

• Horizontal cracks usually radiating out from the corners of the window. Upside down triangle is for center failure.

Question 22

Structural:

The masonry veneer is a load bearing part of the structure. (True or False)

Answer 22

• False

Question 23

Structural:
End bearing for steel lintels in masonry should be at least ____ inches. End bearing for wood headers should be at least ____ inches.

Answer 23

• 4 inches, 1.5 inches

Question 24

Structural:

Give two examples of how you might differentiate between a roof leak and a condensation problem in an attic.

Answer 24

• Condensation tends to be more uniform and widespread than leakage. Condensation is uniform laterally across the roof. Leaks tend to run down sloped roof surfaces following gravity.

Question 25

Structural: | What is the main function of a collar tie?

Answer 25

- Collar ties help prevent rafter sag

Question 26

Structural: | Why is it common to find sagging roof sheathing on trusses?

Answer 26

- Trusses are further apart than most rafters. Trusses are often 24 inches on center and some common (OSB), plywood and waterboard sheathings are not thick enough to span 24 inches without sagging under live load.