I live in Boston and just moved into a 1899 house that was converted to condos. The unit was remodeled, except one area -a storage area that contains electrical and plumbing systems including the sump pump and a dehumidifier. This area is about 30 sq feet and lined by brick with crystals and evidence of moisture. It runs under the stoop of the front of the house and under the city sidewalk. The dehumidifier runs most of the time, keeping the space 50-60% humidity, electrical bills are high at $240 for the last month (we have gas heat, total home only 995sq feet).
The last storm showed some leaking from the sidewalk above, so we moved the electrical outlets, but this space is so odd I am confused how to water proof it. The remainder of the basement has a trench and sump pump. This odd storage space contains pipes running every which way. A vapor barrier on the exposed brick is possible, but the water is coming from above. The city takes years to repair a sidewalk.
Should I try to add some sort of flashing to the sidewalk above? Add the vapor barrier to the walls? Rip up the sidewalk myself?