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Structural Defects Are The Leading Cause of Mold - Don't Ignore These Warning Signs

Uncategorized Jan 12, 2023

Key Points

A recent study evaluated the contribution of building issues to mold proliferation in dwellings. The study investigated 503 homes of patients suffering from respiratory diseases and found that building defects were the leading cause of mold growth, with water infiltration through leaks in roofs or walls as the top contributor. These results highlight the importance of health professionals being able to request home inspections and for city health authorities to address building issues in order to prevent mold proliferation.


• In the United States and Europe, 20% of homes have been found to have mould growth. Both immediate and long-term health effects are significant.
• Globally, a number of governmental and nongovernmental groups have produced recommendations regarding the dangers of indoor mould to human health. Mold-infested building home examinations have uncovered a wide range of danger signs.
• Practically speaking, the specialist conducting the home inspection should be able to pinpoint the main source of mould growth.
• Following home visits to buildings with mould issues, the purpose of this paper was to pinpoint the main reasons of mould propagation.

Studied Buildings

A surface in a living area was deemed to have mould if the total area of all the surfaces with mould was at least one square metre. A technician who has visited hundreds of homes over many years made the initial evaluation of the mouldy surface.


• The specialist started by carefully inspecting the house visually. They detected potential air pollution sources in each room.
• The technician next answered questions on a form that asked about the aforementioned details as well as the number of home occupants.
• After then, numerous pieces of equipment were used in the patient's bedroom and living area.
• A Qtrack to gauge the relative humidity and outside temperature. A wall hygrometer (Protimeter survey master) was also used.
• Three groups of environmental issues were identified.
• Wall humidity measurements made it possible to identify the origin of mould growth.


436 homes had at least one structural flaw, whereas 67 homes in the study group had none. The distribution of the mould infestation's causes is depicted in Figure 1. Nearly 50% had to do with structural issues.

The primary structural issues that contribute to the growth of mould are listed in Figure 2: water penetration, damp increase, and thermal bridge.

The status of the ventilation is shown in Figure 3.

Figure 1 shows how mould infestation causes are distributed based on building issues. water damage is 12% or 43% is condensation.

The primary structural issues that contribute to the growth of mould are listed in Figure 2 as water penetration, damp increase, and thermal bridge. As demonstrated, water penetration accounted for 72% of the structures where mould proliferation was found, damp rise accounted for 21%, and thermal bridging accounted for the final 7%. The number of buildings where mould proliferation was caused by water infiltration was more than ten times greater than the number of homes where mould proliferation was caused by thermal bridges, hence water infiltration was the main source of mould proliferation.

The status of the ventilation is shown in Figure 3. In fewer than a quarter of the cases, the latter was operational.


The study has both advantages and disadvantages. The size of the sample and the standardisation of the visits made by a single qualified technician are its strong points. The restrictions relate to the focus on apartments.
• The literature already in existence has emphasised a wide range of mould formation risk factors. Risk factors include the age of the structure, the number of residents, the proportion of individual homes to apartments, and poor socioeconomic level.
• Mold growth is most commonly caused by issues with buildings. Figure 3 depicts the ventilation's condition, which was either present or nonexistent.


Mold growth in inner-city high-rise structures is primarily brought on by structural issues. These results demonstrate the necessity of expert house inspections.


Felipo R, Charpin D. Structural Home Defects Are the Leading Cause of Mold in Buildings: The Housing and Health Service Experience. Int J Environ Res Public Health. 2022 Dec 12;19(24):16692. doi: 10.3390/ijerph192416692. PMID: 36554570; PMCID: PMC9779167.



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