Leaks and other visible moisture, as well as high humidity, can also be signs of dampness. Dampness provides the ideal conditions for the growth of mould. Dangerous Effects of damp and mould can harm your health and home. Even in cases when mould is not present, moisture can be harmful. Additional health risks from excessive dampness include the growth of bacteria, viruses, cockroaches, dust mites, and other pests.
People who are allergic to mould may experience allergic reactions or asthma symptoms after exposure to mould. However, even without mould, indoor humidity contributes to upper and lower respiratory issues, including asthma attacks. When exposed to airborne mould particles, anyone—allergic or not—may experience irritation of the eyes, skin, nose, throat, and lungs.