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Flood and Leak Preparation/Remediation Guide

Flood and Leak Preparation/ Remediation Guide

Water damage (including damage from freezing) is one of the most common and most costly types of homeowners insurance claims. Every year, about one in 50 homeowners files a water damage or freezing claim, accounting for 29% of all homeowners insurance claims, according to the Insurance Information Institute. (forbes.com) With the right knowledge and preparation, we hope that you can avoid very costly damage even if you experience a flood event.  That’s the purpose of this guide and kit. 

Before: secure lawn furniture, vehicles, and windows and doors

Flash Floods can happen with no notice, but if you have time, try to do as much of the following as possible to keep water and wind out.

  • Park your vehicle in a garage above street level if possible  

  • If high winds are forecasted, install hurricane shutters or plywood over windows and glass doors if possible. Store lawn furniture and bikes in a garage and roll or move heavy decor like pots to sheltered places.

Before the storm/flood: Take photos of your property inside and out for documentation (which hopefully will not be needed!).  Move valuables like photos and jewelry to a high, safe place in the home.

Before: prepare a basic survival kit for weathering the storm at home, as many times floods cause power outages.  

  • Drinking water (one gallon per person per day for several days, for drinking and sanitation)

  • Food (at least a several-day supply of non-perishable food) 

  • Manual can opener (for food)

  • Battery-powered or hand crank radio and a NOAA Weather Radio with tone alert

  • Flashlight

  • First aid kit

  • Extra batteries

  • Whistle (to signal for help)

  • Dust masks (N-95 if possible) (to help filter contaminated air)

  • Plastic sheeting and duct tape to protect furniture from water

  • Hand sanitizer

  • Moist towelettes, garbage bags and plastic ties (for personal sanitation)

  • Wrench or pliers (to turn off utilities)

  • Local maps

  • Cell phone with chargers and a backup battery

  • Various buckets for leaks

Minimum Tools for Clean-Up:

  • Utility knife with extra blades for cutting drywall

  • Pry bar and hammer

  • Heavy duty gloves

  • Heavier plastic tarp(s) for temporary repairs and drywall disposal

  • Heavy duty “contractor” bags for disposing of wet drywall, carpeting and water-damaged items

  • Flat shovel for removing debris from floor

  • Wet-dry HEPA vacuum

During the storm/flood: 

  • Don’t open windows or doors during the storm, as flying debris can cause serious injury!  Contrary to urban legends, you shouldn’t open them to “equalize pressure” during a tornado situation, either.  

  • Keep your weather radio tuned and cell phone on for local updates and take shelter in an interior room or the basement if advised against tornadoes. 

  • Occasionally tour the house and peek at attic space (if you have one) to check for leaks. Use buckets to contain water and if a steady drip of water starts to come from one area, use a utility knife to cut through the ceiling drywall to let the water run out faster and avoid blowout of the ceiling.  

  • Don’t stand in or walk through water to avoid risk of electrocution


  • Venture outside only when it’s safe to do so (the storm has passed). 

  • Alert authorities if your power is out or there are downed power lines near your property

  • Don’t drink tap water unless it’s deemed safe to do so

  • Take “after” photos inside and out

  • Be aware of displaced wildlife like snakes, alligators and the like!

  • Make repairs as you are safely able to do so.

  • If you have to leave your home for safety, write the date, your name(s), destination and phone number on a prominent wall as information for rescue teams

The Clean-Up:

When flooded by a hurricane or flash flood, the waters invading your home contain a variety of pathogens such as E. coli, Salmonella, and Shigella; Hepatitis A Virus, agents of typhoid, paratyphoid and tetanus, as well as agricultural or industrial chemicals (OSHA.gov).  This means that contents and surfaces that came in contact with floodwater from outside must be sanitized and completely dried within 48 hours or disposed of; do not let them just “dry out”.  Then after cleaning and drying, mold prevention treatment can be applied. 

Tips for salvaging household items (adapted from haywardscore.com):

Papers and clothing 

  • Move outside and spread out in sun

  • May wash clothing in washer

  • Papers and clothing soaked in contaminated water should be disposed (clothing will contaminate washing machine)

Solid wood furniture

  • Move outside to dry thoroughly

  • Remove drawers

  • Tip back to expose underside

  • Wipe down with clean rags

Area rugs

  • Can be professionally cleaned with extraction method

  • Washing them in your machine may contaminate the machine

  • Rugs with foam backings should be disposed

Wall-to-wall carpeting

  • Since it must be cleaned and thoroughly dried within 48 hours, and this is hard to do in the case of large areas of carpet, disposal is most common.

Padding under wall-to-wall carpet

  • Dispose because it is difficult to completely dry.

Upholstered furniture like couches and recliners

  • Must be cleaned and thoroughly dried within 48 hours.  

  • Move them outside if the weather is dry

  • Tip back so that the underside is exposed

  • Remove cushions and covers if possible to dry faster. 

  • Use a wet-dry shop vac to remove as much water as possible, then use fans to circulate air over them continually.

  • Thoroughly soaked furniture is unlikely to be completely cleaned and dried: disposal is recommended.

Drywall:  If any water pooled on the floor near walls, then it likely contacted the bottom of the drywall and insulation and needs immediate attention to get the walls dry.  The following is adapted from PopularMechanics.com:

  1. Wearing a respirator mask, safety glasses and gloves, remove baseboard with a prybar or hammer claw.

  2. Place a tarp under the area you will start to cut to catch drywall debris.

  3. Mark walls 6-12” above the high water line (use a chalkline or laser if possible) and cut using a utility knife, drywall saw or light circular saw set at ½” depth.

  4. Punch out the drywall under the cut with a hammer and remove it from the studs.

  5. Cut away insulation using a utility knife, making sure that you remove all damp insulation.

  6. Haul out debris on the tarp and repeat until all affected walls are open.  

  7. Use a wet-dry HEPA vacuum throughout the process to keep dust down

  8. Remove electrical plates to promote drying within the wall.

  9. Disinfect floors and cavities with a degreaser/cleaner and pressure washing to clean out all the bacteria from floodwater (not necessary if it was clean water) (moldfreeliving.com)

  10. Use drying equipment (see below) to expedite drying.

If entire ceiling areas and walls are soaked (from roof damage), remove all items you wish to salvage in the room before tearing out drywall and insulation (best done by professionals).  Unfortunately, all wood, tile, and vinyl flooring must be removed eventually because incomplete drying in-between and under the floor will cause mold to grow (also best left to professionals).  

How to use Drying Equipment: Drying out a house is actually an art.  Remediation companies use their equipment to get the right humidity, airflow, and temperature (HAT), the elements necessary for evaporation, during different stages of drying. The following advice is from the article Expediting the Drying Cycle:

  • Low relative humidity (RH) is necessary for drying, as moisture in materials and air seek equilibrium. The lower the RH of the air, the quicker the wet materials will give up their moisture to become equal with the moisture in the air.  Use any dehumidifier available from the first day, in order to get the RH as low as possible and keep it there.  It’s important to use the wet-dry HEPA vacuum as much as possible before switching on fans, as dust can plug filters on the dehumidifiers and reduce their drying capabilities. 

  • Airflow measured in feet per minute (FPM) is more important than cubic feet per minute (CFM).  Airflow speed at the beginning must be aggressive, preferably 600 FPM or more.   This is why professional blowers sit low on the floor to move air directly across flooring surfaces.  Alternate the blower between rooms if you only have one blower. 

  • Heat is needed when rates of evaporation begin to slow down, usually on the second day of drying.  At this time, if you have a room heater, turn it on and slow down fan speeds to 150 FPM.

  • Consistently low RH is the most important goal, because RH drives drying. Toward the end of the drying job, it’s possible that only one airmover is needed in each room (where the drying goal has not been met) with all available dehumidifiers running.

Wait until everything completely dries in the walls (consistently low RH can indicate this) before applying any anti-mold products.  Here are some recommended mold preventatives:

  • For a large area, consider having it soda blasted by professionals to remove remaining debris and mold from the structure in hard-to-reach places. 

  • DIY Fogging to prevent mold growth:  EC3 Mold Solution Concentrate and Fogger, $495

  • Laundry: EC3 Laundry Additive, $23

  • Use the Mold Guard and Air Angels after drying to continue elimination of mold in all areas.

  • Use TotalClean to wipe down surfaces like countertops, windows, cabinets, mirrors

Consider using an Ozone Generator to kill mold and remove odors:

  • Ozone generators should only be used once all surfaces that can be cleaned are thoroughly cleaned (walls, floors and ceilings too!).  

  • Ozone is not as effective in areas of high humidity, so running the air conditioner or a dehumidifier in the space to get the humidity down (60% or less) is advisable.  Central air conditioning and any exhaust fans must be shut down when using the ozone generator, though, because you’ll want the ozone to stay in the space. 

  • Use fan(s) within the space to circulate the ozone.

  • Ozone generators cannot be used in the presence of people, pets or plants, but once these are removed, they can be quite effective in removing smoke.  Follow all instructions to seal up the space and allow it to work for the full time advised before ventilating.  Contact HypoAir regarding rental, or local restoration companies may rent ozone generators.