Hi,

Yes, the Boston Ivy will still loose its leaves in Winter. Maybe consider using creeping fig instead as it's an evergreen climber. Does take longer to grow and cover the wall though.

English ivy, Boston ivy, Virginia creeper and climbing hydrangea all attach themselves to supporting structures via the same means - aerial rootlets. It has been documented that NONE will destroy the mortar in masonry walls (brick, stone) provided the mortar is in good shape and structurally sound. But they are all difficult to remove from structures without leaving markings and residue on the walls.

Like any other plant from temperate climates, Boston ivy will not fair well indoors at a constant temperature and low light levels (even a very large skylight will not offer the same degree of light intensity as growing a plant outdoors). These sorts of plants also need to go through an annual vernalization or cold period where they remain dormant or inactive (and lose leaves if not an evergreen). Depriving them of this cold period with a constant year round temperature will eventually weaken them sufficiently that they will decline and die. Both English ivy and creeping fig are more commonly grown as houseplants as well as in the garden so would work better for this purpose than the Boston ivy but will pose their own issues.