Q. (Re- questions 2254, 2255 above) What if the person lives on a houseboat or a boat year round or just in the Summer?
Does he have to have an eruv built around the boat to carry in and out?
A. Since the sea or the lake are a Karmelis, one may not carry items from or to them.
However, if he was able to build a proper eruv with mechitzos that includes the boat, it may be permitted.
Horav Shlomo Miller’s Shlit’a opinion is that due to the complexities of building such an eruv, an expert Posek on these Halochos should be consulted.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a