A: Top Down/Bottom Up refers to a control option on some window shades and blinds that allows the user to either lower the top portion of the blind or raise the bottom. Many times both the bottom and top can be raised and lowered simultaneously, giving you even greater control over the natural light in your room.
Top down/bottom up shades do not require any special mounting or tools, and look and function much like ordinary shades and blinds. Simply leave the top of the blind flush against the top mount to give the appearance of a regular shade. This allows you to manipulate the shade from the window sill (pulling it from the “top down”).
You can also leave the bottom flush against the sill and manipulate the top (expanding the shade from the “bottom up”). This is perfect for when you still want sunlight but not glaring sun at sunrise or sunset.