moldy construction and alternitives to them

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Subject: Mold in New Housesfrom the IAQ List - an excellent, thought-provoking post by Steve Temes. Iunderstand that Dr. Craner is involved in helping educate buildersabout this problem. There is also some research available where theresearcher actually followed the storage of the building components andobserved moldy lumber being used in construction.From: Temes <AirwaysEnv@...>Subject: Mold in New HousesMold in new construction has been one of my pet peeves for many years.In the last few weeks, a mold remediation project I am familiar withinvolved the removal of a length of triple 2x10 span girder at greatexpense. The costs were for an engineering study to design support for thefloor in order to replace the girder. The subfloor for the room above thegirder had to be removed in the process, with all sorts of complications.As any good framing contractor knows, you install the moldiest pieces oflumber where they won't show. So the center piece of 2x10 in the girderwas the moldiest and precluded the consideration of treatment in place.Several floor joists were also heavily contaminated with visible blackmold.The project had to do with a sewer waste line that leaked onto a gypsumfirewall and the floor. No water directly impacted the moldy framingmembers on the basement ceiling. However, the elevated relative humidityin the basement had caused the mold to grow extensively off of the surfaceof the lumber. In other words, the mold was in the grain when it came outof the lumber mill but was raised well off of the milled surface after ithad been in the damp basement.The remediation contractor would not even propose the job unless he couldremove the moldy floor joists and girder for fear that he would not passclearance testing (another necessary topic of discussion for our group).The point is that mold spores, when placed in a damp environment, willgerminate. When they grow into a 3-D patch of fuzz rather than remaininside the wood grain, the spores can become airborne and occupant exposurewill occur and new spores will find new amplification sites, ad infinitum.If these moldy pieces of lumber were flagged in the new construction, itwould have saved thousands of dollars in the remediation as well asprevented occupant exposure to spores.Ironically, the contractor actually had to "remediate" the new pieces oflumber he had purchased to replace the contaminated joists before heinstalled them. No kidding. And these were the best hand-picked piecesthat the local lumber yard had available.I have posted on this topic before. I would like to see local constructioncode enforcement officers fail framing inspections when they find"excessively" moldy lumber. Wood comes from the forest with mold on and init. It comes out of the mill with mold on it - some grades of lumber moreso than others. Then it is sometimes transported and stored wet before itgets to a job site where it can sit in a mud puddle for weeks. I think theframed house that gets wet in the rain until it is sided is only a verysmall part of the problem.This post is in no way intended to be in support of Kenn's borate treatmentprocedures, which I am not familiar with, but it does point out a scenariothat could have been avoided if the "new" lumber didn't already containviable mold spores. I would prefer to see moldy wood not leave the lumbermill rather than install it and spray it with something. But once it is onthe job site and being used, maybe that is all you can do to help thesituation.Steve Temes, CHMMIndustrial HygienistAirWays Environmental ServicesDear group;

It is for this reason that our next home will be of steel frame construction with MR drywall throughout. It will also be built on a concrete slab (no wooden subfloor to grow mold when the plumbing does leak) and the flooring will be decorated concrete or ceramic, non porous tile. The exterior cladding and finish will have no cellulose to aid fungal growth (vinyl or brick over concrete panels maybe?) Cherry and I will be battling this fungal syndrome for quite a while, it seems, and are trying to take an active response to getting and staying better. It seems that the longer we can go between exposures, the better we feel! Thus, limiting your exposures is a big part of the cure.

Just last week it was mentioned that when the AC ductwork in the crawl space was "remediated" in a home in Tallahasse a major relapse occurred. Crawl space homes, by nature are death traps for us mold sufferers. AC ductwork by nature leaks. That is why I think it would be much healthier for us to have it in an attic built of steel framing and a fairly dry (low humidity) environment instead of in the crawlspace sucking in those spores!

Those of you with knowledge of this need to expand on this thread and maybe we could set up some guidelines for truly mold free construction for us really sensitive types. I realize that the costs would be higher, but the benefits clearly outweigh the costs.