Lucerne Valley ductwork is rural-property work similar to Phelan in scale (150-300+ linear ft of duct on larger custom homes) but with additional off-grid and solar-paired considerations. Some Lucerne Valley off-grid homes use propane forced-air furnaces with central ductwork that runs on solar-paired electric blowers. We verify solar/battery capacity supports the blower amp draw during the duct work commissioning. Other Lucerne Valley homes use mini-split heat pumps as primary HVAC and have no central ductwork at all. For grid-tied solar Lucerne Valley homes, central ductwork supports either central AC or central furnace systems and follows the same install patterns as valley cities. Lucerne Valley attic temperatures hit 140°F+ in summer same as Hesperia, so R-8 insulated flex is mandatory on every full-replacement install.