The spots also may be mold.
Brown mold spots on ceiling.
Mold damage aside from water damage mold growth on your ceiling is also a likely cause of the brown spots.
Walls are also common habitat for brown mold to grow especially in damp or dark spaces such as ceiling room and basement.
Typically your only recourse is to repaint.
Sometimes the water droplets dry out and only leave behind the stains while in other cases the dripping seeps through the ceiling and you have a leaky ceiling with brown stains.
It may not have been mold.
Cleaning soot from ghosting is extremely hard.
Once mold shows up on your ceiling it isn t long before a small patch evolves into a thriving colony.
Brownish spots on the ceiling can be fluids gross i know from the bugs.
To test for mold touch the spots with a cotton swab that has been dipped in household bleach.
In early stages brown mold may look like spots or discolouration.
Cigarette smoke can cause staining via the same principle as ghosting.
The second cause of ceiling discoloration may be related to moisture but is not directly caused by it.
When a portion of the ceiling stays damp for an extended period of time a yellowish brown mold stain can form overhead.
We had a wasp problem a while back and the exterminator asked if there were any brown spots on the walls or ceiling explaining that this is a sign of infestation.
Ceiling stains can draw eyes away from even the most beautiful living room dining or kitchen.
If there is plumbing problem that happens inside the wall structure mold will grow from the inside and slowly spread to the outer part if not removed.
I suggest you call an exterminator.
In this case it was due to areas of missing insulation in the attic.
Your best option for a base coat to cover water stains on the ceiling is an oil based mold resistant stain blocking primer in a shade closely matching that of the existing ceiling.
Some species of brown mold may even grow into thicker mushroom like blobs.
Left untreated the mold stain may grow and become darker over time.
Depending on the colour of the surface it is growing on it may appear brown or nearly black.
Mold may not seem very threatening but the danger.
The soot attaches to cold spots on the ceiling.
If left unchecked brown mold can grow thicker taking on a fuzzy or even hairy appearance.
The outer surface is not the only place brown mold can grow.
How to safely clean mold off of a ceiling.