Mystery Dry Brown Ceiling Stains
I live in an old home, built in the 60s. After moving in, I noticed a gradually growing brown patch over the downstairs toilet (which is directly beneath the upstairs toilet). I monitored it, never finding it to be wet or even damp, but it continued to grow until I got concerned about it. I cut about a 6x4 hole into the ceiling, which was sufficient to cut away all of the brown part. The sheetrock was dry and everything in the ceiling up to the toilet and pipes above it were dry. I peered all around, felt all around - nothing! I cut new sheetrock and (badly) patched the ceiling using joint compound and spackle, but did did not repaint it yet. Within six months, light brown stains began to reappear around the edges of the patch that I placed (so that they make a square stain). Now the stains are getting darker and the spackle is flaking in areas under the stain, but the ceiling is not soft or damp at all! Is this some kind of water leak, or possibly something else? Please help this amateur!