Help! Will mold grow in my walls? Do I need to make a hole? Professional? Four days ago I let my bath water run too long (~45mins @~2 gallons/min). Nothing spilled over, but water was dripping frm the ceiling in living room below the tub (probably leak in the overflow)! The dripping mostly followed a beam/edge (not a corner) & spanned ~3.5ft in length, 2in in width. I put several small holes in the drywall to speed dripping. The very thin drywall along the edge was slightly crumbly; the dripping (~2 gallons total) stopped within ~20mins. I rented a dehumidifier & purchased a moisture meter 6hrs later. Readings along the beams in that area & w/in 2ft diameter were 26-32%; readings were no more than 19% along beams/edges elsewhere in the house. After running dehumidifier 48hrs & waiting an additional 36hrs, readings are 17% where I poked holes, but still 29% along beam 3ft frm the holes. No staining/bulging, but 2 very thin 10in cracks near holes Note: live in SoCal=low humidity? Thanks!