Concern for mold from water damage

Hi Wendy, Yes, your ceiling absolutely should be checked even after the leak is fixed. Here's the standard process we use for tub/shower leaks: 1. Check for moisture still trapped: We use a moisture meter on the ceiling drywall and joists above. If it's still reading over 16-17%, it needs to be opened. Paint can trap moisture and hide mold. 2. How to determine how much to replace: - Look for any bubbling, sagging, soft spots, or brown/yellow staining - Press gently, if drywall is soft, it must go - Cut a small inspection hole about (6"x6") in the worst area and check with a flashlight - if you see black/green spots on the back of drywall or on insulation, mold has started - Rule of thumb: Remove ALL damaged drywall + an extra 12-24 inches beyond the visible stain in all directions. Mold spreads beyond what you see. 3. Prevention: - Remove wet insulation... it doesn't dry properly and will grow mold - Let joists dry completely (use fans/dehumidifier for 48-72 hrs) - Treat wood with antimicrobial (like Concrobium or Benefect) - Replace with Type M/R (moisture resistant) drywall and prime with mold-resistant primer (Zinsser) - Make sure bathroom above now has proper waterproofing - cement board + RedGard membrane If the leak was active for more than 24-48 hours, I would strongly recommend opening the ceiling. Mold can start in 24 hours. I can come check it with a moisture meter and thermal camera at no charge if you're in Durham area. Just let me know. Philip | GET IT DONE Renovations.

The only true way to know is to remove a section of the ceiling and inspect. That being said, as long as the leak has been fixed and the drywall has dried out properly, it should be fine. Health Canada doesn't recommend routine mold air testing, as the results aren't always reliable. I'd suggest checking the ceiling with a moisture meter first, and if there's any concern, opening a small section to see what's going on behind it.

Hi, i would look for any sort of discolouration (brown, black) I would also recommend feeling the area your concerned about for any softness in drywall. Damp drywall will crumble up and will be extremly soft. So if your able to poke a hole thru the drywall with your finger, or you see any paint dropping down, I would then remove the drywall before it turns to mould.