Author Topic: Anyone have experience preventing/abating mould growth after a flood?  (Read 2715 times)


  • Handlebar Stache
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Hello all,

As some of you may have heard, Alberta has had some widespread flooding, and unfortunately, my Dad's house has been flooded.  We haven't been allowed back to do anything yet, but my sister snuck in to get some pictures, and check on the cat.  (The police escorted her back out of town, before she could catch the cat).

There was about 4 feet of water in the basement, but it has drained down to about 4 inches now.

This happened Thursday, and they are saying it will be at least Wednesday before we can get in, to do anything.

I know we'll have to gut everything back to the studs, to about a foot above the water line, but past that, we aren't sure what to do?  The whole town of 12,000 people has been flooded, so contractors/services will be hard to book, and very expensive (our insurance here doesn't cover overland flooding, so this will all be coming out of my Dad's pocket).

Also, does anyone have experience with trying to salvage electronics/tools after a flood?  His (brand new) furnace was likely submerged about a foot (in the back of the garage) along with the hot water tank, his power tools, and the washer/dryer.   I think the town had the power turned off, before things flooded, but we don't know for sure.

The town will be without power for an undetermined amount of time, but he has his girlfriend's generator, to power some things.  I have also reserved a water pump (we thought it would have 3-4 feet of water left) but now I'm not sure if we need to buy the pump, or not.

Any tips or advice is welcome.

« Last Edit: June 24, 2013, 10:21:37 AM by Self-employed-swami »


  • 5 O'Clock Shadow
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I'm sorry you have to deal with this. I had recurring water in my basement and I know how stressful it can be. My situation was never as bad as this, but I did learn a few things.

In general, mold needs moisture. So your first task is to dry everything that can be dried, and trash everything that can't dry fast enough before too much mold begins to grow. Since the house itself was soaked, that means removing everything that got wet as quickly as possible. The house (floor, walls, etc.) will not dry quickly if the humidity is high.

When you have electricity, buy/borrow/rent fans. Special floor-drying fans work really well, but even a few large box fans will make a huge difference in the speed of drying. Run them continuously, and if the outside air is dry, try to set up a flow to bring fresh air into the flooded space.

Bleach is your friend. A 10:1 diluted solution will help stop mold from growing. (Stronger solutions aren't needed and are more likely to damage surfaces.) Once you get the muck and debris cleared out, bleach the areas that aren't drying quickly.

As for tools, they might be OK or might need minor repairs. Anything with electronics may be damaged beyond repair, or the cost of repair may be so high that it's not worth it. Circuit boards do not like water, and often the "repair" is simply a replacement. I hope someone else on the boards can be more helpful.

Set up a staging area for cleaning and drying articles that you want to save, and make a place to store trashed items (preferably far from the house, but keep in mind that trash pickup may not resume for quite a while).

When you work on the site, be safe. Heavy boots or shoes and work gloves that fit well are a must. If you want to be very safe, make sure everyone's tetanus vaccinations are still valid (they only work for 10 years). Bring enough water to drink and to clean your hands before eating or leaving the site.

If you have paper-based mementos that you'd like to salvage (photographs, for example), there are procedures that can really help. If documents or photos are completely water-logged, put them in sealed plastic bags and freeze them. That will keep them stable until you figure out how to handle them. Conservators can do wondrous things with soaked photographs, but it takes the right equipment and skill. It can be expensive, but by freezing them, you can explore your options.

As for the cat, try to contact local animal groups. I know that in the US, the ASPCA and other organizations mobilize after such events. They can often work with police and gain access to houses to care for animals when the general public cannot. Cats can survive long periods without food, but they do need access to safe drinking water. Once you're reunited, if you're sure the cat hasn't eaten in over a week, watch it carefully when you begin to re-feed it. If you think anything is wrong, don't hesitate to take it to a vet immediately. Though rare, hepatic lipidosis (fatty liver) can be brought on by abrupt starvation and can quickly kill a cat. The good news is that with quick access to proper nutrition, it can be reversed.

When you begin feeding the cat again, feed it high-quality wet food. None of the cheap mass-market stuff; this is the time to go for the expensive brands (if you don't already feed this type of food already). (A high protein diet will help avoid hepatic lipidosis.) The can's label should have chicken/fish/etc. as the first ingredient, not "chicken meal" or "fish meal" and should not contain plant-derived proteins (if possible; it can be hard to avoid corn gluten). If the cat gets too much carbohydrate (usually a by-product of eating food with too much hard-to-digest protein), hepatic lipidosis is more likely to occur.

Good luck!


  • Handlebar Stache
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We will hopefully have someone retrieving the cat today (he is on contract with the town, and will try to motor on over to the house, and catch her).  She had a full dish of food when my Dad left, and she still had food when my sister saw her.  I'm planning on taking her to the vet for a check up, as she might need some preventative antibiotics, after spending so much time around that yucky water.  She should also have relatively clean (toilet) water to drink, as that seems to be her preferred place to drink, over the water dish anyway.

I just hope we can get in there soon, before the whole house becomes toxic!  My Dad would like to be able to move back in, as soon as we've gutted the basement.

It was concrete, with carpet, so we'll be throwing away the carpet, and just cleaning the concrete, along with gutting back to the studs.

I've gone ahead and ordered the water pump as well, because 4 inches of water, over 600 square feet, is still a lot of water to get out, with a shop-vac.  And I'm sure my Dad's neighbours will also want to pump out their basements. 


  • Handlebar Stache
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Also portable dehumidifier will work wonders on getting every last bit of moisture out.


  • Senior Mustachian
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If the electronics weren't powered on when they got wet, and you let them dry completely before trying to turn them on you might be OK.  Water doesn't necessarily do damage to circuitry outright, it's often sparking and arcing that's caused when power goes into wet circuits that causes the problems.

If the power is off to your house, the first thing I'd do is turn off the main circuit breaker.  (Don't want any shorts happening and causing fires whenever they do turn the power to your neighbourhood back on).

I'd run a dehumidifier and as many fans as you can get a hold of constantly to try and dry things out.  Flood waters are dirty (bacteria and sewage) so you're going to want to clean what can be cleaned as quickly as possible with some bleach. 

Rip your carpets/underpadding out ASAP, they're garbage and will just keep things from drying out.  Rip out all of your drwall (to a foot above the flood mark or so) as soon as possible (it's going to be full of mold after a couple days of being wet).  You're going to want to hit all the walls (and ceilings) that haven't been soaked with some bleach solution as well . . . because they'll start growing mold just from all the humidity they've been exposed to from the flooded lower section.  Don't forget to open up every wall cavity you can think of that might have become wet . . . you don't want to forget about a pool of water that's trapped between a wall somewhere.

Pink fluffy insulation is also toast.  It's going to trap a lot of moisture and debris, so the faster you can rip it out, the less overall house mold you'll be looking at.  Upholstered stuff, pillows, beds, anything of that sort is toast.

Home depot sells something called 'Concrobium' which is an anti-mold spray.  Once you've got everything dried out and you start replacing everything, spray all the studs and anything in wall voids thoroughly with this stuff.  It makes a coating that will prevent any mold that's started on the materials from continuing to grow and release spores into your Dad's house.


  • Handlebar Stache
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I'll simply add to what has been said that once you're dried out, relax a bit.  Take your time with the repairs since you'll be paying out of pocket.  Usually events like this attract fly-by-night contractors so be sure you hire someone licensed and bonded, or what ever the professionals usually are in your area.

And, mold needs 3 things to grow.  Moisture, food and the right temperature.  For this reason, air movement is probably better than heated air.  So, lost of fans and fresh air.  Hope the cat is ok.


  • Handlebar Stache
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Thanks guys.  I'll go look for that mould spray stuff as well, before it sells out.