Mold in the Craw space

[hdyankee]

My mold problem is similar to bedazzle in some ways. I would like to stop the mold problem before it gets worse and I don’t know smack about HVAC.

Back ground:
My home is in Fredericksburg Virginia, seven years old (2200 square feet), two story, and the craw space is over 36” clearance for the most part. Air is conditioned by York system Diamond 80 - HDQ24SC (in the craw), Heat Pump Model - E1FDQ24SQ6E (Outside), AC/Unit outside - H1RA024S06A, I have another unit in the attic.

I was in the craw and noticed the mold during a pest inspection. The mold is on the bottom of the rafters, in some places on the rafters where the wood is exposed and mold on some of the insulation between the rafters. The insulation is the fiberglass role type. There is also some mold on the AC pipes and the unit itself.

The vapor barrier is terrible. It is not snug against the load bearing columns and it does not meet the cinder block wall in all locations. Not to mention the thousand holes in it from my dog running around and there is nothing under the Diamond 80.

There is condensation coming off the unit under the house. The technician told me to insulate the bare metal on the unit to reduce condensation and to insulate the pipes from the unit. It looks like whoever installed the unit did not insulate part of the air handler. I used some towels and got up about 2 quarts of water.

I am monitoring the RH level in the craw and it is consistently over 60 percent. I closed the vents around the craw and it seems like the RH is worse. My question here is should leave the vents open for now. Also should I buy a dehumidifier and what kind. They vents are not air tight and I wont be done with the project for about a month. My other question is the main square air pipes that run the length of the house have a lot of condensation coming off them and is that normal

Plan:
First I plan on cleaning and insulating the unit and pipes under the house first. Second step is to clean the rafters and insulation. Does anyone recommend this mold killing product (BenzaRid) http://www.traskresearch.com/mold.htm. Or a product called Microbe guard http://www.microbeguardinc.com/detail.php?PID=2; Or is there another alternative? I thought about Clorox but I don’t want to stink up the house. Plus I read that Clorox does not penetrate wood to kill the mold on the inside. Lastly I think I need to put up another vapor barrier, close the vents and insulate over them to block all the holes etc.

Any suggestions are welcome.

[drk]

Never heard of those products Also if their is mold on the out side of the unit their will be mold on the inside.

[teddy bear]

Originally posted by hdyankee


The vapor barrier is terrible. It is not snug against the load bearing columns and it does not meet the cinder block wall in all locations. Not to mention the thousand holes in it from my dog running around and there is nothing under the Diamond 80.

There is condensation coming off the unit under the house. The technician told me to insulate the bare metal on the unit to reduce condensation and to insulate the pipes from the unit. It looks like whoever installed the unit did not insulate part of the air handler. I used some towels and got up about 2 quarts of water.

I am monitoring the RH level in the craw and it is consistently over 60 percent. I closed the vents around the craw and it seems like the RH is worse. My question here is should leave the vents open for now. Also should I buy a dehumidifier and what kind. They vents are not air tight and I wont be done with the project for about a month. My other question is the main square air pipes that run the length of the house have a lot of condensation coming off them and is that normal

Plan:
First I plan on cleaning and insulating the unit and pipes under the house first. Second step is to clean the rafters and insulation. Does anyone recommend this mold killing product (BenzaRid) http://www.traskresearch.com/mold.htm. Or a product called Microbe guard http://www.microbeguardinc.com/detail.php?PID=2; Or is there another alternative? I thought about Clorox but I don’t want to stink up the house. Plus I read that Clorox does not penetrate wood to kill the mold on the inside. Lastly I think I need to put up another vapor barrier, close the vents and insulate over them to block all the holes etc.

Any suggestions are welcome.

Closing vents will not work without a good vapor retarder on the earth. Recover the earth with plastic with snug fit to pier/walls. Cover with enough gravel to stop air flow under plastic. Now closing vents will stop outdoor moisture from entering the crawlspace. Use a 100 pints of dehumidification per 2,500 sqft. to maintain less the 50%RH. This will stop ducts sweating with needing insulation. Removing visible surface mold is recommended. EPA has good recommendations mainly soap and water. Check Santa Fe HC on web. 135 pints per day with low electrical use and low temperatures.

[teddy bear]

Originally posted by teddy bear

per 2,500 sqft. to maintain less the 50%RH. This will stop ducts sweating with needing insulation. [/B]

Should have stated " This will stop ducts sweating without needing insulation."

[hdyankee]

Thanks for the reply Teddybear; I was hoping you would reply based on other threads. I opened all my vents last night. I read the EPA recommendations for mold cleanup. It states as you posted - soapy water and wood cleaner for my problem. That is pretty strait forward. What mil plastic do you recommend for the vapor barrier and where do you recommend buying it from? I guess what I am asking - is the Vapor barrier plastic anything special? Price is always the issue. Lastly should I remove the old barrier or go over it? I looked at the Dehumidifier from Check Santa Fe – WOW. 1500 hundred smacks, not cheap – but as the saying goes.

[teddy bear]

Six mil plastic over the old plastic is OK. Get it from any building supply. Any a/c contractors could supply the Santa Fe 100 pint as a pickup for twelve hundred. New horizontial Santa Fe 90 for three hundred less available in 30 days.

[wmcarlson]

I am a professional mold remediation contractor who uses BenzaRid and Impact to treat mold in HVAC systems. It works very well with a mold fogger.

You should fog your crawl space. It is the best way to treat mold in there and completely cover the are.

BTW always ventiallate the space, never close it up or the miold will return no matter what you do.

Bill

[uktra]

Wmcarlson--opening up vents to let warm moist air into a dew point crawl in Virginia is bad advice. Teddy bear is correct, seal the ground completely, close off the vents, and use a high capacity unit.

[cem-bsee]

read at BUILDINGSCIENCE.com
CDC.gov
EPA.gov