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How to Have A Mold free Home

Table of Contents

Stop All Water Leaks

Keep Interior Humidity under 52%

Outside humidity in San Francisco is normally around 50%.  In living and working spaces we find interior humidity to be between 40% and 52%. When the long term humidity exceeds 52% it becomes a concern. Humidity can be reduced by turning on the exhaust fans in the kitchen and bath, as well as opening the windows. Ventilation needs air coming in and as well as air going out.

You can purchase an inexpensive humidity gauge from Amazon, Home Depot, etc. If you can measure it, you can control it. Everyone wins this way.

Water Leaks

If you see a leak try to stop it as soon as possible by turning of the water source, closing a window, or any other method appropriate. If you are unable to stop the leak and it is severe, then call the Fire Department. If you are a tenant call your Property Manager or Landlord immediately. If it’s 4 am leave a message and follow up as soon as the office opens. 

The sooner professional drying begins the less likely that mold growth will occur. Everyone wins this way. Call a professional remediation company – they will have drying equipment. They may also remove the baseboards to facilitate better drying.

The property owne wins with less water damage and probable mold growth. Cleanup billing will be significantly less. If the flooding if from “water down” such as a rain storm, call your property insurance company. If the water is from the “bottom up” as in “flooding” call FEMA flood insurance.

By taking immediate action the occupants – owners or tenants – usually are not displaced for a lengthy time. Property damage is less, also.

Tenants may also wish to consider renters insurance. Be sure water damage is a covered loss.

NOTE: Notify building management as soon as possible. It’s much easier and faster to clean up wet contents than wet, moldy contents. Some, or all contents may be lost to mold.

If you suspect this is brown or dirty water spill (sewage spill or from a toilet), block off the area immediately and notify building management or phone a professional remediation company. 

Do not try to clean up this type of spill. 

Do stop the water source, if possible. 

Leave the area. Wait for professional evaluation.

Elevated Humidity

If moist air from your morning shower is exhausted immediately, mold is much less likely to grow in your bathroom and surrounding areas. To test the efficiency of your exhaust fans, turn the fan on. Then take one square of toilet paper and place it below the exhaust grate for the  fan. If the paper sticks to the grate, the fan is working properly. If not, contact your property manager or landlord.

No Insulation in Perimeter Walls Increases Humidity

San Francisco is an old City and insulation wasn’t considered necessary in the past. So, in an older building if you place your bed or sofa immediately next to a perimeter wall, you will probably see discoloration (mold growth) on the wall and adjacent furniture. To avoid this, keep all furniture a minimum of 6″ away from perimeter walls. Mold will grow on wood, too.  It is unrealistic to expect a landlord to tear down walls to insulated your apartment, so work together and keep your furniture 6″ away from perimeter walls.

Too Many People Living Increases Humidity

Residetial housing costs as well as rents in the Bay Area are high. People sometimes are forced to have roommates or office mates this situation. You can purchase an expensive humidity meter and when the interior humidity reached 52 degrees, turn on the exhaust fans in the kitchen and bathrooms. Also, don’t overstuff closets. I know that’s a hard one, but you will be well served to rent a storage space for your extra contents rather than stuffing them in a closet. When a closet is adjacent to a perimeter wall that has little or no insulation condensation occurs. This is often enough water to allow mold growth on closet contents. You can avoid this situation by allowing air circulation around the contents and/or dessicants.

Using communication among all occupants, you can have a healthy home for a long time!

The Importance of Routine Maintenance

Planning for routine maintenance will reduce water leaks and some causes of elevated humidity. Look especially at the rain gutters and confirm they are free of debris and leaks. Make sure the grade next to the foundation of the buiding flows away from the structure in all areas. Also, cut back overhanging trees and remove all vines from the building. The roots of vines can grow through brick and stucco. This will allow water intrustions beind walls where it may be undetectable for years. This can cause a very expensive repair. 

Inspect the heating or HVAC system’s filters. Don’t reuse filters, regardless of what the manufacturer claims. Don’t consider washing filters as some vacuum cleaner manufacturers recommend. Because the water says in the folds of a HEPA filter. This water causes mold growth. So, you’ve got a filter that is growing mold that will infect the entire building when you turn on the system. 

Inspect all bathroom, kitchens and laundry plumbing for leaks. A non-penetrating moisture meter can become your best friend. If you find a leak at the base of a toilet then the wax ring has usually failed. This wax ring should be replaced during the next plumber’s routine visit. Amazon, etc., sells both penetrating and non-penetrating moisture meters. 

Take a good look at all the grout in the kitchen and baths. If you see breaks or missing grout, get a handyman to carefully remove and replace the grout. If tiles need to be removed, and installed before 1981, then assume those tiles contain asbestos and lead. The asbestos will be in the leveling compound and adhesive. The lead will be in the sealer on the tiles. Assume or test. Be safe.

Make sure all windows and doors close completely without drafts. This will reduce interior VOCs and other dusts. A simple water stripping product around the door to a garage can significantly reduce VOCs. This skinny, self stick, inexpensive product can be found at most hardware stores, Amazon, etc.

Annually inspect the exterior for any signs of deterioration or water damage.

Every property has difference maintenance needs, so adjust this list to fit your needs.