Embodiments of the present invention are directed towards fire blocking apparatuses that include fire skirts that extend off edges of solar panels installed on roofs. The fire skirts are configured to block the gap between a solar panel and the roof surface on which it is installed to prevent or suppress the ignition for spreading of fire underneath the solar panel. Some of the fire skirts are heat or fire sensitive and are configured to the melt, deform, or otherwise be altered upon the application of a threshold temperature such that the fire skirts block the gap between the solar panel and the roof surface. Other embodiments are directed towards fire skirts that include a solar panel mounting surface and a shelf surface configured to accommodate ballast or fasteners to affix the solar panel to the roof surface. Such embodiments can be formed from pre-scored or pre-folded sheet materials.