O.K., How Dangerous is Mold to a Home's Survival/Market Value?

I'm the poster with the "Bleach Bombs" thread going, so I'll make this short, because a local contractor whose trustworthiness I don't doubt told me this afternoon "Your home is rotting from the inside out [because of mold in the attic plywood]."
This isn't my home; it's my Mom's. I'm sick to my stomach thinking this guy is right. Once mold starts--and of course it starts in every home the minute the home is built--does it ALWAYS mean a death sentence?
Not to carry the analogy too far, but it almost feels as if someone told me I had cancer. (I've busted butt and almost killed myself in a freak accident last year working on this place.)
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snipped-for-privacy@yahoo.com wrote:

No. You've been listening to too many hysterical "investigative" news reports, and the people who've sprouted up a brand new industry to capitalize on the hysteria.

You need to dry the place out and see what you have. If you get rid of the moisture problems, the mold will die on it's own. If you have wet insulation or chipboard, it might need to be torn out and replaced because you can't dry that stuff out. If the mold is Stachybotris (sp?), you might need to do a little more extensive cleanup, -- washing it, drying again, and painting with a fungicidal paint like you use in bathrooms ought to do it.
Bob
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It does not start in every home the minute they are built, only in improper building practices. Yes your moms home roof deck will rot. That is why proper venting now is important, vent it right and the mold will die. Mold needs the right environment to live, your underventing is giving it the moisture it needs to flourish, vent and the moisture will be removed and the mold will not survive. Mold is everywhere, but needs moisture to live. It is good you worry but dont worry to much, if damage has ocured you will find out, it may not have yet. Just get proper venting done now. There are specific guidlines for minimum venting needed, you can`t have to much, but you obviously have way to little. After you vent in a few months you can look into any damage that may have occured.
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Well, it;s not GOOD news, but if you (A) fix the water problems, (B) treat the affected and any other wood with boracare or permethrin or someother preservative, and (C) dig out any wood that's actually started to rot, and fill with epoxy.
then it should last as long as you will.
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Sounds like two problems? 1) Warm damp house air is getting into the attic, and condensing into moisture, possibly due to lack of proper vapour barriers in the ceiling? In certain cases a non permeable (usually oil paint) can partially act as a vapour barrier. 2) Proper venting to the outside of the roof/attic space. Absolute minimum in our climate is 3 square feet per 1000 square feet of area; distributed so as to ensure cross ventilation of the roof space in all conditions. In some cases a venting fan can be used. Also any insulation in the ceiling should not obstruct/interfere with airflow into through the soffits/overhangs of the roof space.
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Terry wrote:

More than two. "Doomsday roofer" (the second contractor to visit to give an estimate) told me mom's BATHROOM FAN vented into a HIP ROOF--I'm highlighting the liabilities--was nuttin' honey compared to the fact years ago mom used an unvented fireplace insert for extra heat. (We live in one of the damn-ed states in this country where unvented propane inserts are allowed.) The heat it generated, plus the fact mom turns the thermostat up to 115 until mid-June, is mixing with the cool attic air to create the moisture. Needless to say, this time I want an electric fan.

ceiling?
act as a

And there is loose insulation in the attic, nothing with a vapor barrier. I asked the roofer if he should vacuum the loose insulation and lay regular down; he said No. That seems strange.

minimum
distributed so

In some

should
soffits/overhangs of

Both contractors gave us estimates in the mid 9Ks for total removal of old roof (two layers) and replacement of plywood. If any of you live in small towns in the Northeast, can you tell me if this is the norm?
Can't thank you guys (and gals?) enough. I'm getting a crash course in House Geology.
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You don`t Need a fan, in fact a fan will draw up downstairs heated moist air increasing your utility bill, and bring moisture up, possibly making different problems. You need passive venting of proper Cu ft for attic volume , to keep attic nearly at outside temps, above dew point. What is your attic temp vs outside temp . It should be close together.
You have no moisture barrier? Have minimal insulation ? How many inches do you have ? where do you live , how cold does it get? What Zone are you in? It sounds like you are underinsulated with minimal moisture resistance as well as under vented and bath- sewer not exited.
No moisture barrier means you are bringing up lower level heat-moisture, in a relativly closed space. Sounds like the attic is a mold pit, Is roof leaking, if not proper static venting, terminating bath-sewer vents outside, moisture barrier and insulation are needed. Who designed , built, this unvented dump, who terminated bath and sewer vents inside? A real hack for sure.
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