If you sell solar, roofing or HVAC, or sell to the companies that do, building permits are the most honest public signal of where work is happening. I classified 77,044 permits issued from Sep 20 to Oct 19, 2026, across 47 US cities and counties. Here is what the three most-requested trades look like.

How the work categories are assigned

Cities don't share a permit taxonomy. Austin uses "Electrical Permit - Residential" and Columbus uses "1,2,3 Family MEP"; others only have free text. I map each permit to one category using keyword rules over the type, work class and description, in priority order:

const RULES = [ [ ' Solar ' , /solar|photovoltaic| \b pv \b /i ], [ ' Roofing ' , /re- ? roof|roofing| \b roof \b /i ], [ ' Mechanical / HVAC ' , /hvac|mechanical|furnace|heat pump|air condition|boiler|duct/i ], // ...electrical, plumbing, new construction, demolition, etc. ]; const category = ( p ) => ( RULES . find (([, re ]) => re . test ( ` ${ p . type } ${ p . workClass } ${ p .…