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Shop Vac for mold in crawlspace?

Hi everyone! We have a serious issue in my home right now. I live with a roommate and her elderly mother, and we share this large and old house with a crawlspace. We have a mold problem. It seems to be coming from a couple places. One being the attic, from a leaky roof section and the other being from the crawlspace, from the exterior cement block walls. The roof problem will be fixed very soon but not right now (today's Thanksgiving), and then we can clean up the visible mold inside the attic. The crawlspace is a different story. We insulated it last year when we installed a new furnace down there in the crawlspace. We put down a thick vapor barrier on the dirt floor AND covered the floor above with another vapor barrier. We did not cover the side walls nor the vents. I went down there tonight to replace the filter in the furnace and almost flipped out when I saw and smelled the mold on the insides of the exterior cement block walls. I'm a little worried and very upset, so I'm posting here for the first time hoping to get some help with my plan. First of all, where do I start with cleaning up the crawlspace? Rip it all out and do it right with brand new vapor barrier material and new insulation? If that's the case, I would need to clean first because of the dirt and dust. That's my preference. That being said, I wonder if a shop vac will work in order to get started? I have a tendency to overdo things, so this project is not too much for me. Has anyone else had to do this? Fixing a bad insulation job that cause such a problem? The shop vac we have is the hardest working machine in our house, but I don't know if we have a HEPA filter. Note: the moisture is from the mega rain storm we had a couple days ago. Thanks for any ideas!!

Re: Shop Vac for mold in crawlspace?

Check out this episode of Ask This Old House, where they deal with mold removal in a viewer's attic.

Granted, it's done by a professional, but the technology that's used is pretty cool. They sandblast it with dry ice pellets, and "vacuum" up the dust with a negative air pressure machine and HEPA filters.

If you do anything yourself, be sure you install a HEPA filter in your shop vac such as the ones from CleanStream; otherwise you'll just end up blowing the mold spores around.

Re: Shop Vac for mold in crawlspace?

If you insulated your floor, then open the foundation vents year-round. Probably put a humidistat-controlled fan in one of them. That is, after you have killed the mold. Gotta keep air moving.

A. Spruce
Re: Shop Vac for mold in crawlspace?

The typical filter in a shop vac is lacking, let alone not being a HEPA filter, which is what you're going to need if you're going to vacuum mold.

I would instead recommend getting yourself some good respirator masks that will protect you from the mold and just get in there and remove the mold covered plastic and insulation, spray and scrub the whole area down well with a bleach solution to kill the mold. DO NOT get bleach on the furnace or you'll rust out the case.

As earlier suggested, keep the vents open and get some air circulation under there. Mold grows in damp environments, getting air movement will go a long way to diminish the amount of mold you have down there.

The foundation walls are porous and will continue to wick moisture whenever the dirt touching it is wet from seasonal rains, snow melt, or even irrigation, so unless you find a way to dry out the crawl space, mold will be a constant issue.

Re: Shop Vac for mold in crawlspace?

I'm old school and therefore I'd do like Spruce. Bleach the mold then s c r a p e it off. Keep the place well ventilated and it won't come back.

Simple? not really.

You will have to exercise caution every step of the way, unless you get a professional to do it. If you don't you will pay with your health. No joke.

Re: Shop Vac for mold in crawlspace?

Thanks everyone for your replies. Since my 1st post, we spent yesterday and good money at home depot getting supplies. The Hepa filter was not as expensive as I thought, but the 25 pint soleus air dehumidifier was expensive. We got a good price on it though...around $120, and it works great especially in the upstairs bathroom that has no fan right now. We also bought a mold test kit to verify whether it is mold or mildew. I saw that TOH episode last night with the dry ice blaster btw. Pretty cool technology! Also, I am starting to look in our upper attic to see if I can find some leaks. Meanwhile my roommate is in charge of the crawl space. This old house of ours is so big and complex. It has been remodeled over the years so it is not easy calculating roof dimensions and all; we have 3 attics, 2 types of roofs, and 2 crawl spaces to inspect! We are always working on this house, but we love it. Thanks again all. I am off to the roof...

Re: Shop Vac for mold in crawlspace?

See you're in the SouthEast US... so you're in a humid environment.
A couple of things:
1. shop vac = bad. it will just blow any spores all over the place. Get a mask and gloves, and wipe the mold/fungi off. If you're going to get the Hepa filter, vacuum and then wipe off.
2. NEVER use bleach to remove mold in a crawl! The active ingredient in bleach is effective - on tile or grout or other impervious surfaces. However, since household bleach is about 99% water, you may wipe away the fruiting bodies exposed, but the main portion of the fungi will still be in the wood and you just gave it more moisture. 'spray it with bleach' is a typical 'good old boy' solution which can often backfire on you!
3. you need to identify why you're having the problem - is the ground beneath the poly dry? do you have a humidity meter and taken readings down there? Be Careful - more vents or fans does NOT always solve humidity issues. The humidistat controlled fan is better than a traditional fan... most of the time.
If the problem is circulation alone, this might help. But often fans merely push or pull more moisture/humidity into a space that needs less.
Good luck, keep us posted.

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