Mould must always have a food source and a source of moisture in order to grow. The food source will need to be organic matter of some sort. In a building, this can be as simple as items like cardboard boxes, drywall with paper backing, plywood, etc. The source of moisture can be from a flood, a leak, or even excess humidity. Mould spores are always present in the air. If both the food source and sufficient moisture are available, mould is likely to grow.

Mold reproduces using the production of small spores. These spores can be compared to the seeds of a plant, though they are much smaller than seeds. Mold spores can survive environments that don’t support normal mold growth. They will become dormant. They will only start to grow once they land in an environment with suitable water, food, temperature, and oxygen.

Large mold infestations can usually be seen or smelled.

Here are some important steps to take: Inspect building for evidence of water damage and visible mold as part of routine building maintenance. Correct conditions causing mold growth (e.g., water leaks, condensation, infiltration, or flooding) to prevent mold growth. Control humidity levels Promptly fix leaky roofs, windows, and pipes; Thoroughly clean and dry after flooding; Ventilate shower, laundry, and cooking areas.

NO- The smell is generated by MVOCs (Microbial Volatile Organic Compounds). Not all molds generate MVOCs, and even molds that do generate MVOC's don't do so all the time. Therefore a mould issue can exist with no noticeable smell.

Yes, in certain circumstances- Small areas of mould less than 10 sq ft (1 sq meter) can generally be completed without professional remediation. This would include things like cleaning mould from window sills, a small patch on a ceiling, etc. Areas greater than 10 sq ft should be completed by a qualified remediation contractor.

Dead mold may still cause allergic reactions in some people, so it is not enough to simply kill the mold, it must also be removed