The good news is that water leaking through the ceiling light fixture is your early warning system. Knowing why water is coming through the ceiling light fixture, where it is coming from, and how to fix it allows you to step in quickly and avoid those devastatingly expensive contractor-driven repairs.
Immediate Responses
Common Ceiling Leakage Problems
Ceiling leakage often falls into certain predictable categories:
Water Leaking Through a Light Fixture
Your home’s exterior is designed for managing water, directing the flow of water along the lines of gravity and away from your house. In contrast, your home’s interior has no such water management system. In bathrooms and kitchens, where water is expected, tubs, sinks, and waterproof flooring contain the water and keep it moving along. In the rest of the house, though, water will carve out its route by following the path of least resistance. The weak point in the ceiling is the hole in the drywall that contains the ceiling light fixture’s electrical box, as well as the light fixture itself. In the lifecycle of a ceiling water leak, water will pool on top of the drywall, between the joists, for a surprisingly long time before you notice it below. Ceiling blown-in cellulose or fiberglass batt insulation compound that problem, since they soak up water like a sponge and slow its downward flow. Acrylic-latex ceiling paint forms a thin waterproof membrane that contains the water for a short while.
String of Water Coming From the Ceiling
When a thin string of water is moving across the ceiling by capillary action, it can be difficult to find its source. Locate a flashlight, then turn off the lights. Standing on a chair, move the light across the ceiling. The water should show as a bright line. Track the water back to its source, then look upward from there. Supply pipes from a bathroom or laundry room located above may be leaking.
Bulge or Bubble of Water in the Ceiling
Sometimes, a circular or crescent-shaped bulge in the ceiling drywall will precede drips. Piercing the bulge will expel the water trapped between the drywall and the paint layer, but it does not solve the more significant problem. If the water is clear, this is a new leak. If the water is brownish and smells moldy, the leak has been building up for a long time. The light fixture may short out and stop working because its circuit breaker tripped. Sometimes, the fixture will continue to work even as water drips around and through it. At this point, you need to take immediate, short-term measures to ensure your safety and mitigate further damage to your home.
Common Sources of Ceiling Fixture Leaks
Water that leaks through and around ceiling light fixtures fall into two broad categories: plumbing leaks or natural water leaks from rain or melting snow. Common sources within those categories:
Copper pipes that have burst or have developed pinhole leaks Faulty pipe connectors that produce water leaks Ill-fitting upstairs bathtub or shower drain assemblies Leaking drainage pipes leading from tubs, showers, and sinks to the sewer stack Rain leaking through exterior flashing around the chimney, skylights, or plumbing or venting protrusions in the roof. Frozen, clogged gutters that form ice dams, forcing snowmelt under shingles and into the attic
Permanent Repairs of Ceiling Leaks
Once you have protected your home and located the source of the water leak, you have more breathing room to fix the leak permanently.
Replace leaky water pipes with new copper or PEX pipes. Check on your shower or tub’s overflow drain. Remove the shower or tub drain assembly, clean out the old plumber’s putty, and replace it with new putty. Repair drainage pipes. Repair or replace exterior flashing (some roofing companies will do this work). Improve ventilation to your attic to combat ice dams before they develop. Install an ice dam barrier the next time you roof your home.
Repairing Your Damaged Ceiling
Water-damaged ceiling drywall and insulation should be replaced entirely. Neither material can return to its same dimensions.
