How do I fix my crumbling bathroom ceiling?

Replace the ceiling with waterproof drywall. Plastic tiles can be glued back on with construction adhesive. Liquid nails or Locktite Powergrab. I suggest you get an exhaust fan or leave the door open after bath or shower.

If you have a window in the bathroom put a fan in the window to act as an exhaust fan. If you don't have a fan get a dehumidifier. They even make crystals that absorb liquid I think it is called Dry Eze or something close to that. Just an ordinary fan will help move the air around but you need something to retract the excess moisture.

Ventilate your bathroom and keep it drier by providing an outlet for unwanted moisture. One of the easiest methods to ventilate your bathroom is to open a window when you're showering or bathing. This allows the heavy water vapor to escape to the outdoors. Ceiling exhaust fans can also help to clear your bathroom from moisture-laden air. Clean and maintain your fan to keep it operating properly. Bathrooms located in more humid regions may benefit from a portable dehumidifier. Place a dehumidifier in your bathroom to extract moisture from the air and reduce the humidity level. These come in a variety of sizes to accommodate any bathroom size.

Until you get the bathroom fixed you could also leave the bathroom door ajar and a fan sucking the moist air outside. That would be better then nothing. I would really look into opening those bathroom windows that are painted shut.

Here is how to open a window that has been painted shut.

1. Slide a putty knife between the stop bead and window sash to cut through the paint seal.

2. Use putty knife to open the joint between the bottom sash and stool (windowsill).

3. Slide putty knife along the meeting rail where the top and bottom sash meet.

4. Try lifting the sash; if it's still stuck, move on to the next step.

5. Force a putty knife behind window stop; if necessary, use two or more knives.

6. Carefully pry the stop from the side jamb using a small flat pry bar.

7. Use a hammer to pull any nails from the jambs.

8. With one stop removed, try lifting the sash.

9. If sash doesn't budge, remove the opposite window stop.

10. With both stops removed, gently wiggle the sash free of the window frame.

11. Cut the sash cords and remove the sash.

12. Scrape the sash of all loose paint, then sand it smooth.

13. Prime and repaint the sash.

14. Install new sash cords and replace the sash and window stops.

Hi this is Peggy. Hope this helps you fix your bathroom. Good luck. The Best Materials for a Bathroom Ceiling | Hunker

1. https://www.hunker.com › ... › Building & Remodeling › Bathrooms

Learn the most common moisture-resitant products for bathroom ceilings, ... Do not use conventional or even water-resistant drywall behind tile in wet areas. ... Outside of the shower/tub area, the biggest problem for bathroom ceilings is ... You can control water vapor with proper ventilation, but the ceiling will still get damp.

Install a vent. It will save you time, money and aggravation in the long run.