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This document provides a "Building Flood Response Checklist" - what to do to protect your building from mold after flooding from a burst pipe or from rising waters and area flooding. These are quick, simple steps to minimize mold damage in a flooded building. Our photograph above shows flood levels marked on a basement stairwell during flooding of the home. All of the mechanical systems were inundated.

If your building has been flooded, this website provides an easy to understand guide for flood damage assessment, setting priorities of action, safety, and we provide special information about avoiding or minimizing mold damage.

Our "Flood Response Checklist" provided in this document lists key actions you should take after building flooding to minimize mold damage, and includes some safety warnings.

We also list after-flood "anti-mold" procedures that do not work or are unsafe - to help you avoid unnecessary expense in dealing with mold after a building flood.

If your building is already moldy or if you suspect mold related illness in your building, we link to a step by step "Mold Action Guide" dealing with toxic or allergenic indoor mold and other indoor contaminants: when and how to inspect or test for mold, when to hire an expert, how to clean up a moldy area, when and how to perform post-remediation mold testing.

If your septic system has been flooded we link to an article outlining what to do about a flooded septic system as well.

Extensive, technically detailed in-depth articles on other mold detection, testing, and prevention methods are organized at our Mold Information Center © Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Respond immediately to building leaks and floods. This means within 24-48 hours all of the critical steps need to be taken if you want to maximize the chance of avoiding a costly mold cleanup project. Basically:

1. Before entering a building that has been flooded review FIRST PRIORITIES: What to Do After a Building Has Been Flooded to address life, health, and safety concerns. An initial building survey is needed to assure that a building is safe to enter. Hazards in and around flooded buildings include risk of structural collapse, risk of septic system collapse, trip and fall injury hazards, electrical shock hazards, fire and explosion hazards where natural gas or bottled gas are present, toxic sludge and materials containing waterborne bacteria, such as the E. coli and Enterococci bacteria, toxic mold growth indoors.
   
2. Stop the water entry. Salvage or protect furnishings or possessions which have not yet gotten wet by moving them to dry areas.
   
3. Remove standing water - this may mean calling the local fire department or other agencies who have special pumping equipment.
   
4. Pump out flooded basements gradually: (about one-third of the water per day) to avoid structural damage. If the water is pumped completely in a short period of time, pressure from water-saturated soil on the outside could cause basement walls to collapse.
5. Remove sludge, mud, and dirt that has accumulated in the building. Beware that often after an area flood such as during a storm or hurricane, public and private sewer backups have left various toxic materials in mud and sludge in and around buildings. See SEWAGE CONTAMINATION IN BUILDINGS for discussion of how to test for and remove sewage contaminants from buildings.
   
6. Remove wet carpets, furniture, contents, and boxes of wet stored items. Store items to be salvaged from the flooded area outside or in a garage, not in upper floors of the flooded building. Otherwise you may accidentally carry mold or other contaminants to other building areas.
7. Check the building structure and mechanical systems again for safety. Now that there is unobstructed access throughout a building, a more thorough and accurate visual inspection should be performed to look for evidence of building movement or broken, unsafe gas or electrical connections.
   
   
8. Remove floor trim and lower portions of walls (such as drywall or paneling) (at least 12") and any wall insulation, in rooms where the floors were wet or flooded. Porous materials like drywall or plaster which have been wet cannot effectively be cleaned and should be discarded.
   
   
9. How Much Drywall to Cut Off After Flooding: If a floor was wet, even if water did not rise up the walls, remove no less than the bottom 12" of drywall as well as any floorboard trim. Water on a floor surface enters and wets the wall cavity and often causes a significant but hidden problem mold reservoir in the wall cavity.
   
   If mold is visible on a drywall covered wall, remove drywall to no less than 12" above any visible mold, including inspecting the wall cavity interior for visible mold. Because drywall comes in 4' widths, it is often economical to remove more drywall than the bare minimum, but to remove it in 4' or 2' increments from the floor as you move upwards.
   
   If removing moldy drywall along a wall surface where the walls were not wet from below, remove all visibly moldy drywall and in addition to removing drywall for another 12" above the last visible mold, also remove drywall horizontally for at least one more wall-stud bay. Inspect the back side drywall which has been removed and the cavity side of drywall which remains in place to be sure there is no visible mold there. (Some writers who advise leaving drywall unless the wall was flooded more than a few inches are mistaken. Ignore that advice as you'll just be asking for a later hidden mold colony in the wet wall cavity.)
   
   
10. Remove upper portions of wall coverings (drywall or paneling) higher than 12" if these areas are wet, or if water entered the wall cavity from above.
    
    
11. Remove ceilings that have been flooded from above, regardless of material such as plaster, drywall, or ceiling tiles. Suspended ceiling tiles which have been wet should also be discarded, and the remaining suspended ceiling tiles removed to permit inspection and drying as well as to inspect for evidence of water overhead.
    
    
12. Remove wet materials (such as areas listed above) until you find a 12" or greater area of dry clean margin.
    
    
13. If mold is already visible or suspected, use containment to avoid air movement from the damaged (moldy) area to other building areas.
    
    Containment (of moldy dust or demolition dust and debris) generally means negative air and poly plastic barriers. "Negative air" in a moldy or dusty work area: by use of fans blowing outdoors from the work area and plastic barriers at its entry keep the work area at negative air pressure with respect to the rest of the building. So dust in the work area does not tend to escape to other building areas."Containment" means that plastic barriers are set up and other steps are taken to isolate a moldy or dusty work area from the rest of a building.
    
    
14. Moldy Surface Cleaning: after rough demolition to remove wet and porous or visibly moldy materials and other items listed above, all remaining loose dirt and debris should be removed, and the remaining exposed surfaces such as wall studs and framing, masonry walls, floors, plywood sheathing, should be cleaned to remove all loose and surface debris. Stains in wood do not have to be removed provided there is no remaining surface mold or debris.
    
    
15. Mold-contaminated Surface Disinfection: after area flooding it is safe practice to assume that septic or sewage contaminants accompanied the floodwaters, so disinfection of all building surfaces should be part of the cleaning process. However as emphasized above, do not permit the use of disinfectant or fungicidal sprays to serve as a substitute for removal of all debris and the physical cleaning of dirty or moldy surfaces.
    
    Surface cleaning and disinfection can proceed before the building has been fully dried, but this process cannot be reliably completed until the building has been dried. Cleaning debris while it is still wet has the advantage of less spreading of mold and pathogens by airborne dust. Cleaning workers should still be careful to avoid being splashed by dirty water or cleaning fluids.
    
    
16. Building dryout using dehumidifiers, fans, heaters, to dry the exposed building areas and surfaces. We find that adding simple fans such as box fans or window fans set on floors indoors, and particularly, pointed at wet surfaces, will significantly speed the dryout process far beyond what an indoor dehumidifier can do if used alone. A comparison of the effectiveness of various building dryout procedures is at WATER ENTRY in BUILDINGS .
    
    
17. Inspect upper building areas and dry or ventilate them. Depending on weather conditions ventilation may mean simply opening windows or use of fans to dry an area. Beware of blowing moist air into a cool building however as that will increase building moisture. A building attic over a flooded basement is likely to have an excessive moisture level so that area needs inspection and may need venting too.
    
    
18. Disaster Aid for flood damage: check with your local and state officials, FEMA (Federal Emergency Management Association), and your local chapter of the American Red Cross to determine if special disaster aid has been made available for people in your area. Your local or state department of health may also know if assistance is available. The American Red Cross is often on the scene of floods and other disasters to provide emergency assistance such as clothing, food, and housing.

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Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP A Guide to Mold Cleanup Procedures
  FLOODS & MOLD CLEAN/PREVENT A Guide to Dealing with Flood Damage & Mold Prevention &r Cleanup of Flooded Homes
  FIRST PRIORITIES When Responding to a Flooded Building
  BUILDING ENTRY PROCEDURE How to Enter a Building After a Building Flood
  DRINKING WATER - EMERGENCY PURIFICATION How to purify emergency drinking water, how to remove odors
  DRINKING WATER - EMERGENCY SOURCES Where to find drinking water in an emergency
  ELECTRICAL SAFETY for Flood Damage Inspectors
  Foundation Inspection for Flood Damage
  FLOOD RESPONSE CHECKLIST Checklist of Key Steps to Minimize Mold Damage After a Building Flood
  INEFFECTIVE MOLD PRODUCTS Ineffective Mold Products and Procedures to Avoid in Mold Cleanup/Prevention
  FURTHER STEPS PREVENT MOLD Further Steps to Avoid Mold Damage After a Building Flood
  WHEN TO STOP LOOKING FOR MOLD after Flooding: When is a Mold Cleanup Job Complete?
  GENERAL MOLD PREVENTION Preventing Future Mold After a Flooded Building Cleanup
  FLOOD DAMAGE RFERENCES References on Mold Prevention and Flood Damage
  FLOOD VENTS How to Use Flood Vents for Structural Protection from Flooding - Flood Venting in Foundations and Enclosures Below Design Flood Elevation
  SEPTIC SYSTEMS & FLOODS What to Do after a Flood - Septic Flood Response, Safety, Health, Maintenance, Repair Advice
  SEWAGE CONTAMINATION IN BUILDINGS how to detect and respond to sewage backups
  SEWAGE PATHOGENS in SEPTIC SLUDGE what are the contaminants in sewage
  Wind Damage to Roofs how to assess and identify wind damage to roofs

• ark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. (727) 595-4211 mark@BestTampaInspector.com 11/06
• Hankey and Brown home inspectors, Eden Prairie, MN, technical review by Roger Hankey, prior chairman, Standards Committee, American Society of Home Inspectors - ASHI. 952 829-0044 - hankeyandbrown.com 11/06
• Arlene Puentes, a licensed home inspector, educator, and building failures researcher in Kingston, NY. 11/29/06
• Repairing Your Flooded Home American Red Cross and FEMA - PDF - English
• Como Reparar su Hogar Inundado American Red Cross and FEMA - PDF - espanol
• Flood Cleanup - Avoiding Indoor Air Quality Problems US EPA Fact Sheet
• Cleaning Up After a Flood Texas Department of State Health Services.

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