ugh--black mold in attic/bathroom drywall--help!

16 years ago

We had mold detectives come out and take pics and samples of mold we discovered in the wall of the upstairs bath today. They're thinking it's stachybotris (or whatever the worst one is)--we have to plastic-sheet it off for now until we can remove the drywall, some of the insulation in the attic to the side of the bath (A-frame house), etc...

HELLLLPP!!!

There's some potential issue with one of the skylights over the bath too--we need to inspect the flashing up there again to see if it allows leaks.

At this point, at the end of a protracted remodel in which we had to spend thousands more than we'd anticipated because of shoddy remuddling by the previous owner (dangerous stuff, some of it, actually, nothing done with inspections/permits), we just don't have the $$$ to have this done professionally. We're pretty competetent DIYers--we've done a kitchen and a first floor remodel (not the electric or plumbing rough-ins, but everything else)...I read the below info on another thread on this forum--are there experts here who could point us in the right direction to do this ourselves? We have goggles, hazmat kind of masks with the big canister filters, we can get the protective suits...can we do this ourselves? We have a garden sprayer, of course...two, actually. What else do we need?

Here's the info I found so far from g'web (thanks, handymac):

"A solution of 1/2 gallon white vinegar, 1/2 gallon hydrogen peroxide, and 1 cup boric acid will kill mold and the mold spores. Bleach will clean mold, but not kill the spores.

That mix will not store well, as the hydrogen peroxide turns to water when let open.

Wear a protective mask---the kind that seal to the face and has replaceable filters. You can use a garden sprayer---the pump up kind----to spray any areas you find that had mildew/mold.

The problem may have gotten into the wall. If so, you will have to remove the drywall on the garage side to kill/clean all the mold. Replacing the drywall can be a two person DIY job with a book explaining the procedure and some work."

Does this sound good? We've put up drywall too, so we can do that. (We did job some of it out, after DH threw his back out midway, but we can do this much) What are the recommended books to read concerning mold remediation?

Thanks so much...the mold inspectors just left...I feel like we got hit with a 2x10 and I'm still reeling from it :(

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Comments (8)

homebound
16 years ago
Here's some info:

http://www.askthebuilder.com/556_Black_Mold.shtml
doobzz
16 years ago
Do you have a correctly sized bath exhaust fan that vents to the outside? Have you ever checked humidity levels in your home? If you dont keep it below 50 percent and vent the bath properly after showers etc it might happen again. Good luck.
mahatmacat1
Original Author
16 years ago
Thanks, homebound & doobzz. We found that link today and are using it, among others.

doobzz, we discovered just recently that our lovely POs *and* the person who installed the vent fans in our new downstairs master suite bath (two fans) just last year (we're still not using them--this remodel has taken so long), ran the ducts out to the soffit vents! Not up through the roof. We had the inspectors here today and the highest humidity level I saw on his sheet was 46%. But we'd had a huge fan in the bathroom for the last few days, so it was probably pretty dried out. Darling DD, it turns out, was regularly taking showers and keeping the door shut on purpose so she could write on the freakin' mirror...o.k., breathe in, breathe out...

We'll be getting the full report soon so I can learn more about the humidity and dewpoint in the room and other rooms in the house.

I'm so sick about this.
davidandkasie
16 years ago
flyleft, at least yours vented outside. the fans in both baths at my house never had any duct hooked to them. then just exhausted BETWEEN the insulation vapor barrier and the ceiling, since 1978-9! the only nice thing i can say is that we had no mold. i have no clue how we did not, but we didn't. i found this when i changed the vent lights out to heat/vent/lights.
mahatmacat1
Original Author
16 years ago
Maybe because your fans were used? We've had them this way too, and no mold until our DD decided that turning on the vent fan when she showered was too much trouble. Even after we explained what could happen and asked her specifically to do it.

You can imagine how I feel about that.
rogerv_gw
16 years ago
Skylights over the bath, now there's a recipe for disaster. We used to have skylights over our bed in our bedroom and just the water vapor given off by our bodies over night caused condensation problems. I can imagine what could happen with the added condensation from a shower or a tub full of hot water.

This sounds like a really bad idea to me.

You have all my sympathy on the mold issues, of course. We just had a similar issue, but it didn't get really bad. The sheetrock had to be pulled out, and I cleaned out the inside of the walls with a water/bleach solution. We left it open for over a year to see if it would get wet again, but ended up finding out that it was a condensation inside the wall thing due to temperature differences.

-Roger
mahatmacat1
Original Author
16 years ago
Hm...they were here when we moved here, and I confess I do love showering and looking up at the tall Doug Firs around our house, and the stars at night, but I wonder if we should get them walled and roofed over. That might be the smartest idea, longterm. You just put it into my head. I will look into it.
energy_rater_la
16 years ago
So what advice did your mold experts give you?

Certainly not peroxide, baking soda & boric acid??
Have you heard of a product called Boracare? It is a mold inhibitor that sprays on & will keep mold in an inactive state.

Understand that you can't kill mold, just keep it inactive. If Relative Humidity (RH) gets above 50% mold growth will be activated again.
You can bleach it, kiltz it...but it is just covering the mold up for alimited time.

I would first look for the moisture intrusion that caused the mold growth. Get a roofer with a good reputation & good flashing education to take a look at the flashing of the skylights.
Is this where the moisture intrusion began?
Also look at the wall covering in your bathroom.
If you have vinyl wall paper this is a source of mold as it traps moisture behind it. Oil based paintd also make a vapor barrer on top of your walls.

The paper backing on the back of sheetrock is an issue. There is a brand called Densearmor or Denseguard
that has no paper backing..

For mold to grow it has to have moisture and a food source
eliminate the moisture first and then determine if the food source needs replacing.

Have an electrician hard wire the fan to come on when the light is turned on. Bath fans should run at least 20 minutes after shower/bath is finished to remove the additoinal humidity that has been introduced into the home.

Best of luck to you.