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things to know about Water Leaks In 2024

Table of Contents

Find the water leak source and shut It Off

If a toilet is leaking there is a valve on the wall or the floor that has a knob that you can turn off. If the knob is broken, use pliers or a vice grip. If the whole house is flooded from a major plumbing break, you will need to call the Fire Department to shut the water off. It takes a special tool.

Determine if it’s “clean” water or “dirty” water.

Dirty water is water that may/probably/absolutely came from a toilet and may be contaminated with sewage.  If you determoine the water is “dirty”, quarentine the area as best you can and take precautions to not track sewage throughout the property. Use plastic bags over your shoes. Be sure to get all children and pets out of the area.

Contact a drying company.

If you can get the moisture out of the walls within the first 24 hours after a spill, you are significantly less likey to have toxic mold growth with an much more expensive mold remediation. That’s where they take the sheetrock and most other building materials out. 

Ofter the water leak will be so significant that you will need to shut the water off at the street. You will need a special tool to do this. Often the fire department will have this emergency too.

If the flooding is from rain there is not much you can do until it stops raining. Move precious possessions high enough so the flood water does not impact unreplacable contents.

Move all children and pets completely out of the area, if possible.

Remember, rising flood water or water coming from your upstairs neighbor may be contaminated with sewage. Protect yourself with as much plastic as you can.

Have a professional clean up and dry out all affected building materials and contents.  This should be done within 24 to 48 hours to reduce the potential for mold growth. Call us if you need a referral to companies that perform this work.

Don't Spread Mold Spores From Your Water Leak

If you suspect a mold problem, turn on a HEPA only air purifier. This is a band-aide and not a long-term solution.
If you smell or see growth, discoloration, black (or other color) of fuzz don’t use a fan – that will spread the mold spores. 

Many people use fans to dry moist building materials. The use of a dehumidifier is a better tool that will extract the moisture both out of the air and building materials. Professional drying does use a type of fan, but that’s a completely different thing done under professional, tight containment.

Confirm the area is dry with an inexpensive moisture meter. 

Clean Up the Right Way So Mold Stays Away

All water leaks need to be repaired and verified water tight. The goal is to find and correct all sources of the moisture, leak or elevated humidity.  This needs to be done before mold remediation takes place.  If the moisture intrusions are not fixed and confirmed leak free, the toxic mold will probably come back.
You can’t see or always smell mold. There are some unscrupulous remediators who do their own testing and have taken advantage of people. Hire an independent, experienced professional mold inspectors. This eliminates a conflict of interest.

National Standard For Mold Clean Up

The National Standard Mold Cleanup is the IICRC S 520 Institute of Inspection Cleaning and Restoration Certification.

If someone you are interviewing for your mold cleanup is not familiar with this national standard, find someone else.

You need to see a CA Contractors License C61 for Water/Mold Remediation, insurance that names you at your address, a written contract that includes a complete scope of work (use your professional’s mold inspection report for the necessary Scope of Work), and usually trade certification.

Testing your Contents is Recommended

You don’t want to cross contaminate your house with mold contaminated contents. On the initial inspection you won’t know if you have a mold problem (unless it is clearly visible) until your mold air lab results come back. We will write a protocol to address  contents if appropriate.

Remember that the cost to clean contents, can exceed the value of the contents.

  • Older Buildings Pre 1981 May Contain Asbestos
  • Older Buildings Pre 1978 or 1979 (San Francisco) May Contain Lead

If you do have a mold problem and need mold remediation in older homes you may be disturbing asbestos and lead based paint.  If you have suspect materials that need removal for mold and are not tested, your safe bet is to assume that lead and asbestos are present. 

The lead test strips are not accurate for a wide variety of reasons. This is especially important if you have young children living in your home.

If removal is done without the proper engineering controls and PPE personal protection equipment, there is a chance of cross contamination and possible health concerns.


 Too Many People Living in Too Small an Area

Most molds love humidity above 55%. The hotter and wetter it is, the better some molds like it. If you see condensation on the inside of your windows you probably have a humidity problem. The use of a temperature humidity gauge may help you to monitor humidity. Turn on exhaust fans or open windows to reduce interior elevated humidity.

Vent the Clothes Dryer Outside

Putting a sock or “dryer bag” on the dryer exhaust inside your garage, crawlspace, or home laundry will elevate humidity. All vents should reach outside air.

Exhaust Fans in Bathrooms and Kitchens that Vent Outside

All exhaust fans should be equipped with a timer or humidistat or motion sensor so they stay on for 20 minutes or until the humidity is 52% or lower. All vents should reach outside air.

Here’s a simple test to determine if your ceiling exhaust fans are working: take 1 square of toilet paper and place it under the vent grill. If the paper sticks to the grill, it’s working properly. If not, that’s a sign there is a problem.

Preventative Maintenance

Other than plumbing leaks, roofs and gutter systems are potential water sources that can leak and create mold growth.

Have a professional roofer inspect your roof annually.

You should always confirm downspouts drain 18 inches away from the foundation.

You should always check to confirm downspouts are connected and not leaking where they shouldn’t. Use a garden hose to add water to your gutter system and then look for leaks.  Gutter guards are a preventative maintenance recommendation.

You should always check that landscaping water systems are not hitting the building. Drip irrigation is recommended.