Our house has a room on a concrete slab (converted from a three season room/porch). We have been getting water seepage through the walls and under the carpet , which has turned the padding moldy and is causing a nasty smell. A local waterproofing contractor has recomended that we install a water barrier between the carpet and the floor ($500.00) . Unfortunately he cannot tell us where the water is ultimately coming from. What type of professional can help us to determine the source of the water ?