wind storm design requirements

[engrreddy]

Hello All,

Can anybody have any suggestion on where to look for "WIND STORM DESIGN REQUIREMENTS" for wood framed house near coast!!

Thank you

 

[frv]

Wouldn't that just be per ASCE-7 (in the US)?

 

[RWF7437]

http://www.windspeedbyzip.com/

 

[RWF7437]

"Archwind 98 will calculate wind loads on structures based on ASCE 7-98. This program will only provide wind loads and is not intended to perform structural analysis using these loads. In general the output includes component wind loads, summary load combinations for design and a listing of the major constants used in the analysis.

"In many cases the constants used by the program are pre-calculated and displayed in editable text boxes. If the user does not agree with the displayed constant, he can directly edit the value on the screen.

"The program addresses most of the structure types addressed in ASCE 7-98 as listed in ASCE 7 chapter 6.

"It is strongly recommended that the user be familiar with ASCE 7-98, Chapter 6 prior to using this program."

 

[cvg]

suggest you ask your local building department that will be issuing the building permit. They will have the local requirements that you must follow.

 

[DaveAtkins]

And keep in mind a single family residence is generally governed by a different Code than other building types.

DaveAtkins

 

[SLTA]

are you talking about Texas? they have a program called the "Windstorm Inspection Program".

http://www.tdi.state.tx.us/wind/index.html

 

[Ron]

as cvg said, check with the local building department. If the county is rather rural, you might check with your state to see if there is a specific building code (many states have their variations of the national model building codes, including Florida, North Carolina, Virginia, etc.)

Most of the codes allow determination of loads in accordance with ASCE 7. Check the particular code to see which version of ASCE 7 is in effect at the time (could be ASCE 7-02 or 7-05...I don't know of any groups still using ASCE 7-98, though it is possible that they are...standards adoption lags behind code adoption which lags behind the state of the practice....)

Also as stated, many states have a separate code for residential, in particular single-family or two family dwellings. Though it probably isn't greatly different in the structural aspects, it can be.

NOW...if you've never done this before, I suggest you involve a senior level structural engineer to review your work or mentor you through the process. It is easy to screw it up, and if you're doing it for someone other than yourself, you can get into a bit of trouble for not doing the right thing.

 

[engrreddy]

Thank you all for your info. and help!!

 

[engrreddy]

existing 2-storey residence in Port Aransas,Texas. Home owner trying to get certified for windstorm Insurance! House was built in 2000. House needs to certified for wind storm specs for about 130MPH. Need to know all design requirements for wind storm strapping, nailing, anchorage,etc.. Any prescriptive methods, tables to check against!!

 

[MiketheEngineer]

See IBC 2003/06 and Simpson or USP caalog

 

[diarmud]

Take a look at the NDS, the AFPA has issued a workbook entitled "Design of Wod Frame Buildings for High Wind, Snow and Seismic Loadings", it's dated 2005.

As mentioned, the local building code will be the driver.
The AFPA also issued "Wind & Seismic", Special Design Provisions for Wind and Seismic" it is dated 2005/2006.

Good luck, sounds interesting.

 

[COEngineeer]

Just look at IRC and make sure you have enough wall to resist the wind (no calculation, just inspection). If I remember correctly, you may not be able to use IRC if the wind is high (cant remember the limit, I dont have IRC infront of me). As far as ties and nailing, you need to look at IBC which leads you to ASCE7.

This is awfully hard though unless you have the original plan. How would you know what hangers they used to hold down the roof? How about to hold down each end of the wall or at openings into the foundation?

Never, but never question engineer's judgement

 

[Ron]

engrreddy...I hope the Texas program is better than the Florida program for same...This could be a high liability issue for you, so be sure you are prepared to do this. It isn't as simple as looking up a few things in tables and blessing the mess. If you are a licensed engineer, you WILL be held to a higher standard than an insurance adjuster or others.

How will you verify the strapping? Are you planning to look in the attic and verify gable bracing in sometimes inaccessible areas? How will you verify the nailing pattern of the sheathing? How will you verify the types of fasteners used? How will you know that strapping was properly nailed?

If tension rods were used in lieu of straps, how will you verify that bottom and intermediate plates and nuts are installed?

Since the house was built in 2000, do you know if deterioration due to water intrusion has occurred? Do you know if the sheathing has been compromised as a result?

A 130 mph wind is nothing to play with. I realize it's a small structure and its macro economic impact is not great; however, it is the protection for someone during a storm and if not, the structure should be there when they return.

Approach this with your eyes wide open.

 

[FSS]

Yikes, nothing like certifying an existing structure for hurricanes with your first attempt at wind design.