I have a terrible smell in my half bath-it seems to smell very organic with a tinge of metal -it started 3 weeks ago. We just had the floor replaced (in July) and the bathroom painted (August). When we tore up the flooring in the kitchen adjacent to the bathroom we found leakage. Come to find out the sink in the half bath had been leaking under the sink and draining out into the kitchen. We had the sink repaired. My husband changed out the toilet and seal as it was leaking, but the smell remains. When I open the window to the bathroom the smell disappears, but then returns when the window is closed. We do not have a basement, only a crawl space. Could this be mold in the walls or something large has died in the wall space. My husband refuses to have someone tear into the walls. Please help me- I am at my wits end.