You can maintain a mold-safe home by following these steps.
Remember: mold is everywhere. When indoor relative humidity is greater than 52%RH mold has a more favorable environment to growth. Mold feeds on the cellulose in dust. It’s important to maintain your relative humidity inside lower than 52%RH. Turning on bath and kitchen exhaust vents as well as opening windows is a good way to maintain lower interior relative humidity. A simple humidity gauge from Amazon, etc., will tell you when you need to turn on the exhaust fans.
Schedule mold validation or clearance before any interior reconstruction begins.
This should not be done by the mold remediation company or other contractors that performed the work. This should be done by a separate company.
All leaks need to be repaired.
After these repairs, take a garden hose and squirt water on the area repaired. Go inside and make sure no water is coming in. This should be done before any reconstruction.
Keep the plastic containment chambers in place.
You can contain the dust from the reconstruction.
Consider using DensArmour products instead of sheet rock.
There is no cellulose to feed mold growth as there is in regular sheet rock.
Mold may still grow on the exterior dust on building materials. The mold growth occurs in dust when the humidity is elevated. This is commercial product and used in things like hotel bathrooms. It is ideal for any subterranean area or anywhere mold growth from leaks is a concern.
Ventilation is very important.
Keep the inside humidity under 52%RH by using exhaust fans. You can put these vents on timers or humidistats. A humidistat will automatically turn on when the humidity goes above 52% or whatever you set. This is the first fix our flippers and biohackers make to their homes. This creates a less than favorable environment for mold to grow.
If your HVAC vents were sealed during the mold cleaning, then change the filter before first use.
If your HVAC vents were not sealed during the mold cleaning, then have the entire HVAC/Heating System including ducts, professionally cleaned.
Do not use any chemicals or water-based products.
There is dust in the ducts. Dust has mold spores. Add water to mold spores and you have mold growth. No duct cleaning company can get all of the water out of the system before mold has an opportunity to grow and hide.
Other Important Things to Know
Keep the plastic containment in place with the air handlers/scrubbers on until your remediation company turns them off. When that equipment is turned off, the machine is immediately placed inside a plastic bag that is fully sealed. Otherwise, there will be back-flow that will/may recontaminate the cleaned area or skew the clearance tests.
To make sure the mold doesn’t return, the MOST IMPORTANT thing is to confirm the water intrusions are repaired completely. Where there is water mold is likely to regrow.
If you have to restore bathrooms or kitchens consider using a DensArmour product. This is widely used for new commercial buildings. It’s made from glass and greatly reduces mold growth. There are companion mud and tape products. Most larger hardware stores have these products in stock.
After flooding or water intrusion, if the professional drying process is started within the first 72 hours, the probability of mold growth will be significantly reduced. Verify with infrared that the area is dry before removing equipment.
Interior relative humidity should register at or below 52%. At or above this level of moisture in the ambient air creates a favorable environment for mold growth.
To ensure regular use of bath exhaust fans, they should be put on a timer or motion sensor with a 15-minute delay. Opening the bathroom window is not an adequate substitute.
Bath, kitchen, and laundry clothes dryers exhaust ducts should vent to the exterior of the building and not into attics or crawlspaces. Commercial laundry facilities should not exhaust close to air handlers. Laundry clothes dryer exhaust vents should be regularly cleaned out as a preventative maintenance measure against fires as well as to ensure proper ventilation.
Interior perimeter walls should be insulated. If there is a constant significant temperature differential between the interior and exterior temperatures with no insulation, then condensation buildup inside of the wall cavities is probable and can lead to mold growth.
Rain gutters and downspouts should be cleaned out at least once per year or more often depending on surrounding vegetation. It is also recommended that gutter guards be installed on rain gutters to prevent excessive debris from entering and clogging the system. All downspouts should drain water a minimum of 18 inches from the perimeter of the building and can be extended easily if need be.
Exterior irrigation sprinkler systems should be directed away from buildings. Whenever possible, sprinkler systems should be replaced with drip irrigation.
Vegetation around the perimeter of the building should be cut and maintained a minimum of 18 inches from the perimeter of the building to prevent holding moisture against the perimeter of the building.
Sump pumps should be tested at least once per year to be operational around Halloween right before our traditional rain and colder weather season.
Bleach should not normally be used to combat a mold issue. Bleach is a water-based product and so it is only adding fuel to the fire, so to speak. Bleach also will not address the initial source of the moisture that caused the mold to develop in the first place. If an area of discoloration has been bleached or removed by other means, and the mold growth comes back in under 30 days, this is a sign of a more significant problem that needs to be professionally assessed and may require professional remediation. Cleaning with vinegar and water with thorough drying is the most effective.
Single-pane glass windows allow interior condensation buildup and subsequent saturation of surrounding building materials. All single-paned glass windows should be replaced with double-pane glass whenever possible.