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MOLD - FREQUENTLY ASKED QUESTIONS

Q:  What causes mold growth?

A:  A combination of low light, warmth, moisture and a host material are required for mold to grow.

Q:  Where is mold most commonly found?

A:  In today's office buildings, mold growth when it occurs is most often found on inner wall spaces.  Mold can begin to grow within days of a moisture intrusion event, but usually becomes noticeable in 3 to 5 weeks after the intrusion event.

Q:  What is a "water intrusion event?"

A: Any episode during which unwanted and uncontrolled water enters an occupied space is a "water intrusion event."  It could be a leaking roof,  a poorly-applied foundation sealant or inadequate drainage alongside outer foundation walls.  Water can enter through poor window seals during heavy rains.  Leaking pipes in interior walls are also a common source of unwanted moisture.

Q:  What should be done if water enters my building?

A:  The worst action is no action.  Wallboard acts as an excellent host for mold growth.  Whenever wallboard gets wet, it should be stripped out immediately - ideally within 3 to 4 days following the water intrusion event but in no case more than one week.  If the removal can be performed quickly, and if the inner wall space is allowed to dry thoroughly,  mold growth is unlikely. 

Water will typically collect along the base of a wall, then "wick" up through the wallbaord paper layer.  Left alone, this is where mold will begin to grow.  Therefore you should remove that wet material - quickly - to at least one foot above the soaked wallboard's highest point.  A moisture meter can help to define these limits, but if you don't have one, take out the wallboard to a height of  4 feet plus one-half-inch  (4'- 0 1/2").  This will ease reinstallation of new material once the wall space is thoroughly dried with fans and time.  

Q:  Is that all I need to do?

A:  No.  The most important thing is to positively identify the source of the water intrusion and correct it, during or prior to repair and drying efforts but always before installing new materials. 

Q:  Can mold grow anywhere else besides the inner wall spaces?

A:  Today's modern carpets are constructed of man-made, non-organic products, and are often laid onto a concrete substrate.  These materials do not provide a ready host for mold growth.   Occasionally, we'll see slight mold growth under wet carpet, especially if the floor was dirty when the carpet was installed, or if it is installed on a wooden substrate.  But more often, wet carpet may be dried (lifted if necessary) and left in place.

All buildings are different.  When water enters yours, try to identify any organic materials that may have become wet.  They're your targets. 

Q:  We didn't notice the water leak until weeks afterward, well after mold growth had occurred.  What do we do now?

A:  The fix - i.e. removing the impacted wallboard - is still the same.  Unfortunately, you now also have the potential hazard of airborne mold to deal with.  Removal of mold-infected materials is best performed by a licensed hazmat contractor.  While that may be more expensive than the services of a general contractor, a licensed, reputable abatement contractor has the tools and experience to remove moldy materials without increasing (or creating) a hazard to the building's occupants.  If the mold growth is widespread, a testing agency/consultant should be retained in order to (a) establish a sensible removal work plan and procure bids for the work on your behalf; (b) monitor the contractor's efforts during removal, and (c) provide air monitoring and a written clearance notice prior to re-occupation of an abated area.