Jesper has extremely sharp hearing, a gift bestowed upon him by the Singularity, that is sometimes a curse, but he's been using it during the renovations so he can hear someone call for him or if someone needs help. So he does hear the thumping but figures it's someone helping.

He is currently fixing up all the chairs right outside the inn, as they're meant to go into the new outdoor patio space, and he's giving them an extra material seal for outdoor weather. At first glance it would look like he's just running his fingers along all parts of the chair, but a closer glance would make all of it shimmer like liquid.

It stops shimmering when Altaïr shows up since he's distracted and he stands, wiping his hands off, wood and metal permanently dirtying them up at the moment. "Perfect, Altaïr. Is it like serious it needs to be redone entirely, or patchwork? I mean, we probably should just replace, but you have a better sense than me."