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Building Entry, Cleanup & Repair After a Flood or other Disaster
Procedures & Checklist Assess, Respond & Minimize Flooded Building Damage, Repair Advice, Mold Prevention
POST a QUESTION or COMMENT about inspecting, cleaning & repairing buildings after flooding from fires, floods, hurricanes, burst pipes, sewer backups, other disasters
Flood damage control procedures & checklist: if your building has been flooded, this article series 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.
This Building Flood Response Checklist sets priorities for what to do to protect your building from mold contamination 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.
This is the first in our series of building flood damage articles on steps to take to safely enter and repair homes or other buildings after area flooding due to
hurricanes, rising floodwaters, burst pipes, or other water flooding.
We discuss safety for people entering flooded buildings, steps to preserve and protect the building from further damage after it has been flooded, how to get mechanical systems up and running again, evaluating for the need for structural repairs, demolition, and cleaning, and avoid mold in a flooded building. Our photograph above shows the authors examining flood conditions in Comonfort, Guanajuato, Mexico.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
FIRST PRIORITIES: What to Do After a Building Has Been Flooded
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.
[Click to enlarge any image]
Listed just below are quick, simple steps to minimize damage in a flooded building. These are the key actions you should take after building flooding to protect life and property and then to minimize flood damage, mold damage, and other safety hazards.
We discuss here: How to get electrical, heating, air conditioning, water piping, drain piping, septic systems working again after building floods. Mold prevention for flood-damaged buildings & homes & burst pipe response to minimize mold damage.
How to minimize mold damage after building leaks or flooding: "Anti mold" procedures that work and ones that don't work or are unsafe. How to clean up, repair & restore a building after flooding, wetting, or other disaster.
If You Have Been Injured
seek medical care at the nearest hospital or emergency facility. Floodwaters are often contaminated by sewage and there
is risk of serious infection if wounds are not cleaned and treated.
Emergency Assistance Telephone Numbers - U.S.A. or in CANADA: call 911 for most U.S. or Canadian communities or from a cell phone: call 112
Emergency assistance numbers for other countries are
to see if there are elderly or infant neighbors who are trapped, injured, or otherwise need assistance.
Help a neighbor who may require special assistance--infants, elderly people, and people with disabilities.
Elderly people and people with disabilities may require additional assistance.
People who care for them or who have large families may need additional assistance in emergency situations.
Check on the condition of and safety of your building, home or business to begin planning for damage control, flood or other damage cleanup, and building or business restoration
Watch out: Do Not Enter a Flooded, Storm Damaged, or Earthquake or Hurricane Damaged Building if the Following Conditions or Hazards are Present:
Flood waters often undermine foundations, causing sinking, floors can crack or break and buildings can collapse.
Collapse hazards:
Watch out: If the building is damaged or has moved off of its foundation: Damage to the building may mean that there is a risk of collapse.
buildings which have moved off of their foundation - ruptured gas or electrical lines are extremely dangerous.
Even the smallest shift of a building on or off of its foundation, possibly less than an inch, can rupture gas piping or electrical wiring, creating a dangerous condition.
Electrocution hazards: If there are live electrical systems or wires: Where electrical wiring is live and wet or under water or even simply
standing in water or on a wet surface without special protection can lead to a fatal electrical shock.
Gas explosion hazards: If there there are damaged, loose, or broken gas piping or other fuel spills that could result in a fire or explosion.
Watch out:Make sure that all of the utilities, electricity, gas, even water, have been safely shut down. Turning off gas to a building is also discussed at Step2.
Buildings that have not been declared safe:
Watch out:
Avoid entering ANY building (home, business, or other) before local officials have said it is safe to do so. buildings may have hidden damage that makes them unsafe.
Avoid disaster areas:
Your presence might hamper rescue and other emergency operations, and put you at further risk from the residual effects of floods, such as contaminated waters, crumbled roads, landslides, mud flows, and other hazards.
Crawl spaces (or flooded basements) that are unsafe -
Flooded crawl spaces may be contaminated with sewage bacteria, mold, rodents, or chemicals.
Flooded crawl spaces may be in danger from collapse of the structure overhead.
Watch out:There may be a danger of electrocution in crawl spaces, especially wet ones, if electrical power remains on.
Continue to listen to a NOAA Weather Radio:
or local radio or television stations and return home only when authorities indicate it is safe to do so. Flood dangers do not end when the water begins to recede; there may be flood-related hazards within your community, which you could hear about from local broadcasts.
Do not work alone:
Watch out: if you fall or are injured and are alone you may not receive prompt assistance. If you must work alone despite this advice, be sure you have a working radio or cell phone to use to summons assistance
Drinking water
may be unavailable or it may be contaminated. Do not assume that municipal water or water from private wells is safe to drink.
When leaving a building because of impending flooding, leave the electricity turned OFF. Do not turn electricity back on until the building is dry and safe.
Watch out: Using a portable electricity generator
in a waterlogged or damaged home in a disaster area after hurricanes, earthquakes, floods can be very dangerous, risking death by electrocution, gas explosion, or by carbon monoxide poisoning. Above we also warned about electrocution hazards in buildings where the electricity has not been shut off.
Gas leak risks:
Watch out: for gas leaks in flooded buildings - flooding moves buildings & causes gas line leaks.
Do not Smoke Near or Inside Buildings that Have not Been Declared Safe -
a ruptured gas line or leaking gas from appliances could cause a gas explosion and fire.
Do not smoke inside buildings. Smoking in a confined area can cause a fire or gas explosion. Do not turn electricity back on in a building where gas leaks could be present. Use a sealed flashlight for inspection, not a plug-in light.
exist in flooded or storm damaged buildings - a mixture of household chemicals, paints, stored gasoline, lead, sewer or septic system backup, debris and possibly asbestos.
Watch out:Do not begin cleanup efforts without understanding the hazards that may be present and be sure to use the necessary protective clothing and equipment.
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.
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.
How to Prevent Mold Growth After a Building Flood or Burst Pipe
If your building has just been flooded by rising flood waters, a burst pipe, a waste line leak, a sewer backup, or other event, immediate action may prevent a very costly mold cleanup.
Review this checklist. If your building already has an actual or suspected mold problem,
See details at BUILDING FLOOD STEPS TO PREVENT MOLD - How to respond quickly to building floods to avoid a mold problem: what steps to take, in what priority
If you did not take the steps in "Building Floods" below and are reading this section days or weeks after the flooding event, a comprehensive building survey for hidden mold or other contaminants may be needed before a full building cleanup plan can be made.
Extensive, technically detailed in-depth articles on other mold detection, testing, and prevention methods are organized at
such as electrical, gas, water or sewer piping to the appropriate authorities.
Reporting potential hazards will get the utilities turned off as quickly as possible, preventing further hazard and injury.
Check with your utility company now about where broken lines should be reported.
Septic system flood hazards:
include sewage-contaminated floods in buildings and risk of collapsing septic systems.
See SEPTIC & CESSPOOL SAFETY; rope off and prevent access to areas over or close to the septic tank until its condition has been investigated.
See SEPTIC SYSTEM FLOOD DAMAGE REPAIR for advice on repairing septic systems that have been flooded. If your septic system has been flooded.
This article series gives action & repair priorities if your building has been flooded, or damaged by another disaster in an easy to understand guide. We describe procedures for for flood damage assessment, setting
priorities of action, safe entry procedures for damaged buildings, first steps to protect a building from further damage, how to dry out the building, how to return the utilities to operation, how to clean up a flooded or damaged basement or building, how to rebuild a damaged building, and how to prepare to minimize danger and damage hazards from future disasters.
We also provide special information about avoiding or minimizing mold damage in wet or flooded basements or buildings.
Flood or Disaster Damage Response Checklist for Building Damage Control
This document lists key actions you should take after building flooding to protect the building from further damage, to get things working again, and to minimize mold damage. We include safety warnings about entering and repairing buildings that have been flooded by storms, hurricanes, burst pipes, or other sources.
As soon as it is safe to do so, respond quickly to building leaks and floods in order to minimize damage to the building.
While it may be impossible to safely enter or even inspect a building before waters have receded in areas of major flooding, hurricane or storm damage, as soon as possible the building should be inspected and the steps below begun.
Watch out:
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, loose or broken gas piping and gas leaks, toxic sludge and materials containing waterborne bacteria, such as the E. coli and Enterococci bacteria, toxic mold growth indoors.
Stop the water entry or other ongoing damage.
Obviously if flood waters are still rising or if a building has already become partly submerged you cannot easily stop water entry. But in other circumstances there are important steps you can take.
For example: turn off the main water shutoff valve, nail down tarps to cover openings or leaks in storm-damaged roofing, direct surface runoff away from the building.
Salvage or protect furnishings or possessions
which have not yet gotten wet by moving them to dry areas.
Remove standing water
this may mean calling the local fire department or other agencies who have special pumping equipment.
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.
Inspect the building more thoroughly for structural damage and safe entry.
Watch out:Temporary structural reinforcement may be necessary to prevent building collapse before entering some buildings for further inspection or for salvaging contents.
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.
Watch out: for contaminated floodwaters or mud: water and mud in flooded buildings may be unsafe to enter due to chemical or bacterial contamination.
Unfortunately, significant mold growth in flooded buildings is likely
unless the flood event is small (perhaps a burst pipe) and the damage is discovered and responded-to quickly. 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. In freezing or very cold weather you may have a bit more time.
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.
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.
Don't forget to check for damaged fuel storage tanks that may float or move during flooding, risking leaky oil or gas piping. Outdoor tanks that are buried may also be damaged by floating.
(such as drywall or paneling) (at least 12") and any wall insulation
See FIBERGLASS INSULATION MOLD , 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.
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.
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.
Remove ceilings
that have been flooded from above, along with ceiling insulation
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.
Remove wet materials
(such as areas listed above) until you find a 12" or greater area of dry clean margin.
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.
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.
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.
Watch out: Cleaning
workers should still be careful to avoid being splashed by dirty water or cleaning fluids.
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
for safety advice and equipment inspection/repair procedures for heating equipment.
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.
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.
...
Continue reading at FLOOD DAMAGE CLEANUP & REPAIR GUIDE for detailed procedures for wet or flooding basement or building dryout & salvage & cleaning procedures.
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In addition to any citations in the article above, a full list is available on request.
[1] REPAIRING YOUR FLOODED HOME [PDF], American Red Cross & FEMA: Federal Emergency Management Agency, FEMA PO Box 2012, Jessup MD 20794-2012. Printed copies of this book are available from the American Red Cross, from your local Red Cross chapter, or by writing to the address above. Web search 10/4/2010, original source: http://www.redcross.org/www-files/Documents
/pdf/Preparedness/file_cont333_lang0_150.pdf
[2] The following are available free from:
Federal Emergency
Management Agency
Attn: Publications
P. O. Box 2012
Jessup, MD 20794-2012
Design Manual for Retrofitting
Flood-prone Residential
Structures, FEMA-114. This
detailed manual explains all the
floodproofing options in language a homeowner can understand.
Manufactured Home Installation
in Flood Hazard Areas, FEMA
85.
[3] The following are available for
free from:
U.S. Army Corps of Engineers
Attn: CECW-PF
20 Massachusetts Avenue, NW
Washington, D.C. 20314
Introduction to Flood Proofing,
John R. Sheaffer, 1967
Flood-Proofing Regulations, U.S.
Army Corps of Engineers,
Pittsburgh District, 1990, 80
pages (Corps publication EP
1165 3 314).
Flood Proofing Systems &
Techniques, L.N. Flanagan,
editor, 1984
Flood Proofing Tests, Tests of
Materials and Systems for Flood
Proofing Structures, Corps of
Engineers, National Flood
Proofing Committee, August,
1988.
Raising and Moving the Slab-
On-Grade House, Corps of
Engineers National Flood
Proofing Committee, 1990.
[4] The following publications are
available from the American Red
Cross. Contact your Red Cross
chapter for more information:
Your Family Disaster Plan
(ARC 4466)
Su plan para el hogar en caso de
desastres (ARC 4466S)
Your Family Disaster Supplies
Kit (ARC 4463)
Su Equipo de suministros para la
familia en caso de desastres (ARC
4463S)
Safe Living in Your
Manufactured Home (ARC
4465)
Are You Ready for a Flood or
Flash Flood? (ARC 4458)
¿Está preparado para una inundación or inundación súbita?
(ARC 4458S)
Are You Ready for a Hurricane?
(ARC 4454)
¿Está preparado para un
huracán? (ARC 4454S)
[5] Clean up References
Many Cooperative Extension
Service offices have home economists and food and farm experts.
Check your telephone book under
the county name. For example, if
you live in Pittsburg County,
check under “Pittsburg County
Cooperative Extension Service”.
[6] Questions on cleaning or disinfecting of specific materials can be
answered by manufacturers of
cleaning products. Check the
product labels for toll free telephone numbers.
[7] References on technical aspects
of floodproofing can be located
through the Floodplain
Management Resource Center, a
free service provided by the
Association of State Floodplain
Managers. Call 303/492-6818
[8] CMHC, Canadian Mortgage and Housing Corporation, "After the Flood — A Homeowner’s Checklist", retrieved 10/21/2012, original source http://www.cmhc-schl.gc.ca/en/co/maho/em/em_001.cfm [copy on file as After_The_Flood_CMHC.pdf]
Mark 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 [Website: www.octoberhome.com ] , a licensed home inspector, educator, and building failures researcher in Kingston, NY. 11/29/06
"Hurricane Damage to Residential Structures: Risk and Mitigation", Jon K. Ayscue, The Johns Hopkins University, Baltimore, Maryland, published by the Natural Hazards Research and Applications Information Center, Institute of Behavioral Science, University of Colorado, November 1996. Abstract: "Property damage and loss from hurricanes have increased with population growth in coastal areas, and climatic factors point to more frequent and intense hurricanes in the future. This paper describes potential hurricane hazards from wind and water. Damage to residential structures from three recent intense hurricanes - Hugo, Andrew, and Iniki - shows that wind is responsible for greater property loss than water. The current state-of-the-art building technology is sufficient to reduce damage from hurricanes when properly applied, and this paper discusses those building techniques that can mitigate hurricane damage and recommends measures for mitigating future hurricane damage to homes." - online at www.colorado.edu/hazards/publications/wp/wp94/wp94.html
Living in the Danger Zone: Realities about Hurricanes, Fran Marscher, IUniverse; illustrated edition edition (April 25, 2001), ISBN-10: 0595170420, ISBN-13: 978-0595170425
American Red Cross - how to contact the Red Cross - for emergency relief: food, clothing, shelter. If you are in need of a shelter during a disaster, contact your local Red Cross chapter - enter your zip code on this web page. - web search 05/31/2010
FEMA - how to contact FEMA - the Federal Emergency Management Agency - Telephone: 1 (800) 621-FEMA (3362), TDD: 1 (800) 462-7585, Fax: 1 (800) 827-8112 or http://www.disasterassistance.gov/daip_en.portal for online disaster relief application - Web search 05/31/2010
Hurricane advice original source - http://www.fema.gov/hazard/hurricane/hu_during.shtm
"Repairing your Flooded Home", American Red Cross & FEMA: Federal Emergency Management Agency, FEMA PO Box 2012, Jessup MD 20794-2012. Printed copies of this book are available from the American Red Cross, from your local Red Cross chapter, or by writing to the address above. Web search 10/4/2010, original source: http://www.redcross.org/www-files/Documents
/pdf/Preparedness/file_cont333_lang0_150.pdf Same document from FEMA in raw text form:
A BRIEF GUIDE to MOLD, MOISTURE, and YOUR HOME, [PDF] U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. - the original source is no longer available at EPA: http://www.epa.gov/mold/moldguide.htm
In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Carson Dunlop Associates provides extensive home inspection education and report writing material. In gratitude we provide links to tsome Carson Dunlop Associates products and services.