mold and mildew effects on wood

huangyhg

mold and mildew effects on wood?
are there structural effects on untreated wood by mold and mildew?
is there an effective means to remove the growths?
effective way is dryness.  to kill it right away, use bleach and keep it dry after that.
never, but never question engineer's judgement
yes.  mold and mildew can evolve into "wood destroying organisms", if left without treatment.
the conditions that allow mold growth (high moisture, food supply (the wood))will cause wood to deteriorate at the cellular level.  this will, obviously, affect the structural integrity of the wood.
you can remove the mold/mildew with chlorine bleach, but you need to be sure you have stopped any moisture intrusion or accumulation on the wood, as mold and mildew will return.
check the vapor drive through the wall.  make sure you don't have a vapor barrier in the wrong place.  there are lots of myths considering moisture intrusion, vapor drive and permeance of the materials.  even though theoretically materials may be designed to "breathe" and release moisture accumulations, in reality that doesn't work well at all.  if water gets into a wall cavity, there is nothing that will drive it back out in any reasonable time frame.  it stays and does huge amounts of damage.
this would be for an abandoned building with leaks through the roof, wetting the 2 floor levels of framing and obvious moisture issues in the crawlspace.
other than feeling obvious softness in the wood when probed, what other ways are there to access if the organisms are destroying the material?  
check the staining.  wdo in an advanced stage will present a black stain.  if you still have brown wood color, though wet staining is obvious, just probe with a pick. if you meet resistance with the pick within 1/4 to 1/2 inch, you're probably ok...just clean it and dry it.
if you are showing any white staining in a black background, you probably need to look at replacing the   
current recommendations for removal of mold and mildew is to use a detergent and not necessarily chlorine bleach. some molds and mildews produce a toxic byproduct when oxidised.
as noted above, the conditions for mold and mildew is the same to produce 'dry rot', or more correctly brown rot.  moisture conditions upwards of 20% will cause this.
the problem with dry rot is that by the time it is noticed, you may have lost 20-25% of the material strength.
dik
loss of structural strength is important, but loss of "building useability" (staining, odors, mildew growth inside walls and behind enclosures, mildow and mold growing unchecked near hvac and attic entrances) are also a money-loser.
ripping out the bad wood, mildewed inside walls and sheetrock, loss of use of building, allergies and lawsuits due to "loss of diligence in protecting the building from water" ....   those will be expenses coming back across your desk.
in the long run, you can't afford to just paint over the bad wood.
structural restoration is the goal.
"inspection of wood beams & trusses"
you have to stop all mold and mildew action asap; it is progressive deterioration.  you have to remove the source of moisture then you have to 'kill' the little beggers.
if it is structure, you have to provide temporary support if required.  it is then a matter of reinforcing the damage in a manner that is cosmetically acceptable.
reinforcing can be done with rfp, epoxied steel dowels, etc.
dik
navfac has some good publications, don't they?