×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

# Interpretation of effective wind area in ASCE7-05

## Interpretation of effective wind area in ASCE7-05

(OP)
I have a question regarding interpretation of the effective wind area used to compute wind pressure on a building.  I am looking at a wall that is approximately 150' wide by 250' tall.  The effective wind area for the 10% edges is going to be smaller than that for the "field" center portion of the wall.  The wall consists of siding panels 12" wide with a continuous span (they span over sub-girts spaced at 4' o.c.).  Regarding interpretation of the effective wind area to use on the field; do you use the total area of the field = 120'x250' = 30,000 or the tributary or effective area of each siding panel of 4'x 1' wide = 4 sq. ft?  This yields a huge difference, especially at zone 5.  I have attached Figure 6-17 from ASCE7-05 showing the pressure coefficient table.  I also attached and excerpt from ASCE7-02 wind design guide.  Questions 19 and 20 basically imply to use the smaller effective wind areas?  If this is the case (especially for a masonry wall, see question 20), when would you ever have an effective wind area greater than 1000 sq ft?

### RE: Interpretation of effective wind area in ASCE7-05

The wind area depends upon the element that you are designing.

For a single screw attaching the panel to the girt, the wind area is fairly small (area trib to the single screw).

For the 12" wide panel, I'd use the 12" x 48" as the panel effective area.

For the girt, I'd use the girt span x 48".

Etc.

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!