ASCE 7-02 / ASCE 7-05 Comparison

ASCE 7-05 has some changes. Among those changes, the ones related with wind load, live load and loading combination can be summarized as follow;

Wind Loads:

1. Clarified and expand the application of Method 1 – Simplified Method
2. Excluded torsionally sensitive buildings from using Method 1.
3. Modified the pressures for parapets and clarify their application for low-slope roofs
4. Added a definition for eave height and clarify footnote 8 of Figure 6-10.
5. Added provisions for freestanding walls and solid signs
6. Added provisions for canopies and free roofs
7. Clarified exposure categories for main wind force resisting systems and components and cladding
8. Provided objective and enforceable criteria for using climatic data to determine the basic wind speed in special wind regions and other non-hurricane-prone regions.
9. Clarified that the basic wind speed obtained from regional climatic data may be less that Figure 6-1
10. Modified provisions for rooftop equipment
11. Expanded required protection of glazing in wind borne debris regions; clarify that it’s required when loads are determined using Method 3; and update referenced standards

Live Load

1. Added needed definitions (balcony and deck) and relocate existing definitions into a single definitions section.
2. Editorially clarified gymnasium and hospital in Table 4.1
3. Organized roof loads into a single area within Table 4.1
4. Added a specific provision for partition loads – Section 4.2.2
5. Clarified provision 4.3 on concentrated loads – relocated roof truss provision to Table 4.1
6. Removed the 20 lb/ft requirement for guardrails and handrails in one- and two-family dwellings, leaving only the concentrated load requirements. Under limited circumstances, it allows guardrails and handrails in factory, industrial, and storage occupancies to be designed for the same loads as one- and two-family dwellings.
7. Clarified distribution of roof live loads in 4.6
8. Clarified provisions by which uniform roof live loads are permitted to be reduced (4.8 and 4.9)

Load Combination:

Additional exception at Section 2.3.2 :
(3) In combinations (2), (4), and (5), the companion load S shall be taken as the balanced snow load, as defined in sections 7.3 and 7.4.

Additional exception at Section 2.4:
Exception: In combinations (4) and (6), the companion load S shall be taken as either the flat roof snow load (pf) or the sloped roof snow load (ps).