STRUCTURAL FRAMING INSPECTION I

1. MODULE 6 STRUCTURALFRAMINGINSPECTION I

2. Building Subsystems • structural framing & foundations • enclosure systems • plumbing • lighting • acoustics • safety systems • electric power & signal systems • HVAC

3. Transfer of forces acting on the building • foundation systems are designed to transmit loads from the structural system directly to the ground • settlement of the completed building must be within acceptable limits • structural systems should be designed to transfer its loads to the foundation • its design must be anticipated in the foundation design

5. Transfer of forces acting on the building • most building structural systems consists of • floors • roof decks • horizontal members that support the floor and or roof • vertical members that support other components • floor and roof decks or beams that support them, are usually on load bearing walls or columns which carry the load downward • structural systems must be designed to transmit vertical and horizontal loads to the foundations

6. Transfer of forces acting on the building • vertical walls and columns carry vertical loads downward but • acting alone they are inadequate to resist lateral forces • to help counteract lateral forces • bracing can be implemented into the system • beams can be connected to columns to produce a rigid frame to resist lateral movement • long walls known as shear walls, in two perpendicular directions act like vertical beams in transmitting forces to foundations

8. Trusses • the strength of the metal connector plates ( gang plates, truss plates) depends on the • grip of the teeth • shear and tensile capacity of the steel plates • identical truss plates are placed directly opposite each other on opposite faces

9. Trusses • when a truss is axially loaded, the wood fibers press against the teeth and they transfer the load throughout the remaining un-perforated sections of the plate • permanent bracing of a roof truss system is done in the field and must comply with the approved drawings

10. Principles of wood construction • when in tension, wood is strongest parallel to the grain • if the cross-sectional area of a wood member is reduced by holes • the net area is reduced • the stress-concentrating effect must be considered when figuring out allowable loads • under constant loads, wood deflection will increase slightly with time

11. Principles of wood construction • wood is very strong when • shear is perpendicular to the grain • wood is not as strong when • shear is parallel to the grain • wood is graded by • species (type of wood) • grade (#1, #2, #3, stud grade) • grade-marking agency • moisture content

12. Principles of wood construction • wood is a natural insulator • 1 ¼” = RSI 0.22 (R 1.25) batt insulation for 1 ¼” has R 3.25 • wood can be fire rated by being pressure treated with fire-retardant elements • wood that is pressure treated for fire or preservative effects do not loose significant strength

13. assignment • Perform exercise #1, questions 1 to 23 • Q 22 • Summarize the general rules governing stud posts built into walls. • Q23 • What general rules govern floor framing supported on flat insulating concrete form walls?