This is a California Fire requirement that all structures built in or next to designated wild lands must have one hour fire resistive construction. Contact your local building department for WUI designated areas. Are you planning to park your tiny in the country? This will apply to you.
This means that all the windows must be tempered and all exterior materials must be fire rated 1 hour. Wood can be pre-treated to meet this requirement. But I recommend naturally non-combust able materials (sheet metal). Also there can be no under eve roof vents or other openings (cat door?) that would allow the fire to enter your tiny.