I have a question about waterproofing a stone porch. The porch is covered with stone (something like marble). There are relatively thin rectangular slabs placed closely together. Underneath, there are concrete blocks. Under the porch is an open storage space. There is rain that is hitting the porch and seeping through the cracks between the stones. In the storage space below, you can see icicles during winter. Some of this water is travelling into my neighbor's outer wall and causing water damage in his living room.
The solution provided to me was to remove the stone, put down an insulating layer to stop the water and cover it with new tiles. I was wondering if there is another solution. Perhaps a clear sealant that can be painted on the existing stone to keep the water out.