Putting up a shop in CA - fire department being a pain

Just three days ago, we worked a house fire that appeared to have originated from HVAC wiring in the attic. Flat roof with about 16" of space between the interior ceiling and roof. The fire was still small, but making a run in the attic space. We HAD to pull lots of ceiling and cut the roof to gain access and spray water on the fire. Yes, the fire was small and isolated to the attic, but if we didn't do what we did, the entire house would've burned down. Guaranteed 100%.
The house behind us (only about 20' away) caught fire in June from electrical wiring to the HVAC. The house had a steel roof installed over the original wood shingles. The steel caused issues for the fire fighters as they were not familiar with it or how to peel it off.