Retractable stairs for attics require an opening of at least 170 cm (the measurement refers to the extension developed between the foot of the loft ladder and the outermost point of the hatch in the opening phase for a loft ladder measuring 300 cm floor-to-ceiling, also taking into account the presence of the operator. For smaller sizes, the extension is roughly the same). For safety reasons it is recommended not to install the products near drop-offs over the floor of the supporting surface (ex. in the vicinity of stairwells), on slippery floors or in the presence of other forms of disconnection of the support surface.