Anyone know a good source of information for wind code and building code in Galveston county?
Start here: MuniCode
You will have to poke around quite a bit but you may find what you need here. Start with Chapter 10, Article III.
The only source for high wind construction is the International Residential Code and the International Building Code. They have the high wind standards in them. ICC has another document but not all inclusive. Galveston County does not have a lock on windstorm construction. It’s the same for all 14 first tier coastal counties (and the eastern tip of Harris County).
Between 1989 and 2002 there was a detailed construction manual designed specifically for windstorm complete with graphics and illustrations. When Texas adopted the IRC that manual was no longer needed and is no longer available.
*Windstorm means any area of 110 m.p.h wind speed or greater (soon to be 100 m.p.h.).
Being that I live in and inspect in Galveston County I still use the graphics and illustrations as well as the “code” paragraph sections of the original manual on a daily basis. No one really knows windstorm construction as it is an act of engineering. Each engineer can have a different wind design of the same plan. Other references are the WFCM, AF&PA, ASCE, etc.
Your best bet is to hire an approved windstorm engineer and ask him/her whatever question you have.