Can mold be painted over or sealed in?
No. Paint and sealer cover the growth without stopping it, and the moisture underneath keeps the mold alive. The growth often returns through the paint, and it can be worse when it is found later. Mold is removed or cleaned after the water is stopped and the structure is dry.
A coat of paint traps moisture against the surface, and the growth continues in the dark. Paint does not treat an active growth, and a surface sealed over a wet area often shows the stain again once the moisture works through it.
The correct order is to stop the moisture, dry the structure, remove or clean the growth and then paint or replace the finish. Skipping any step is the usual reason a mold problem returns.
How do I know if the mold is serious?
Size, location and the material it is growing on decide how much work is needed. A small patch on a painted surface is different from growth inside a wall or under a floor. The technician measures the moisture and the spread, and explains what is involved before any work starts.
Growth that is larger than a small area, that is inside a cavity, or that has been growing for a long time, usually needs containment and removal. A smell alone does not confirm mold, and a surface that looks clean can still be wet behind it.
If anyone in the home has a breathing condition, allergies or a weakened immune system, ask a doctor for advice about the exposure. This site does not give medical advice, and the technician will not diagnose a health effect.
Do I need an air test after the mold is removed?
An air test can confirm that the air has been cleared after the work, and it is useful where the job is large or where a clearance is needed. It is not always necessary. The technician will explain whether a test is useful for your job and who should carry it out.
A visual check and the moisture readings are the main evidence that the work is complete. An air sample adds information about the airborne spores, but it has to be taken and read properly to be meaningful.
Ask who will take the sample, how it will be analysed and what result will be treated as clear. The answer should be written down before the sample is taken, so the owner knows what the result means.
Why is the mold back after cleaning?
Mold returns when the moisture that fed it is still present. A source that has not been found, a cavity that has not been dried or a material that was cleaned but not removed will all allow the growth to restart. The technician traces the return to its cause.
A surface that was cleaned and then left wet is a common reason for regrowth. The cleaning removes the visible growth, but the spores and the moisture remain, and the growth restarts in the same place.
Repeat growth in the same spot is a sign of a continuing source. The source must be found and stopped, and the area must be dried to its readings before the work is treated as finished.