16
Mar
Causes of Mold Growth in Homes
Mold growth in a home can be caused by a variety of design factors and human factors, such as water intrusion through the building envelope, plumbing leaks and poor air circulation and ventilation – and contribute to negative long-term health effects to you and your family!
Long term and continuous sources of moisture settling on various surfaces of the home provide ideal conditions for mold to grow.
Let’s start by looking at how water can get into your home:
- Rainwater entering through the roof, walls, or foundation due to mechanical damage, or poorly waterproofed penetrations going through these assemblies. Moisture can enter a home through doors, windows, skylights, chimney flues and vents that are not properly sealed.
- Groundwater: High levels of groundwater can seep into a home through a damaged foundation, faulty sump pump, basement walls or basement window wells.
- Humidity: High levels of humidity can occur naturally in homes due to cooking, showering, and other everyday activities. If humidity levels are not controlled by proper ventilation, it can lead to condensation and mold growth on various surfaces, often in enclosed spaces such as bathrooms, kitchens, and laundry rooms. Condensation in unconditioned (unheated) spaces such as attics, basements and crawlspaces due to leaky or uninsulated ducting can lead to mold and mildew growth
- Plumbing leaks: Leaks from plumbing fixtures or pipes can create hidden water damage within walls, floors, and ceilings. Sewage backup and flooding from natural disasters or plumbing problems can cause significant moisture problems in a home.
There ware many ways you can mitigate and prevent water damage to your home. While this is not an exhaustive list, the below are some common examples:
- Monitor and inspect visible piping throughout the home, and consider installing water detectors under sinks and around toilets, near washing machines, and around boilers and hot water tanks
- Regularly service high-efficiency furnaces, boilers and water heaters; these appliances create condensation as a by-product of burning natural gas, and sometimes rely on condensation pumps to drain away condensation (depending on setup)
- Using the bathroom fan and kitchen exhaust fan every time you cook and use the bath or shower.
- Replace old single pane windows, or windows >25 years old, with modern double or triple pane windows
- Regularly maintain sump and sewage ejector pumps, and provide battery backups for these devices
- Inspect and monitor shower and bathtub tiles, especially the grout and caulking details, to ensure they are damage free
- Hire a roofer to inspect the roof, attic space, skylights and any other roofing penetrations on a regular basis, ideally 1-2 times per year, to prevent water coming into the attic and through wall assemblies. Roof shingles and flashings should be continuous and damage free, and all openings from vents and chimneys properly sealed against the roof surface
- Consider hiring a company specialized in inspecting perimeter drains to perform a camera scope inspection, checking for damage or backup of the drainage system. Ensure basement window wells are clear of debris and any other exterior drains are not clogged.
- Ensure any ductwork and plumbing that travels through an unconditioned, unheated space, such as attics, basements and crawlspaces, are adequately insulated, to prevent condensation accumulating within the ductwork. Attics and crawlspaces should be adequately ventilated as well.
- For homes built on sloped, graded lots, consider providing drainage, especially on sides of the home facing uphill, such as digging swales around the building. Consult landscaping experts for options.
- Ensure that deck, balcony and patio surfaces are adequately sloped to shed water away from the building.
