Mold 1. Problems

What About Mold from Moisture Problems in Buildings

We expect that molds growing on damp surfaces indoors can get airborne.

COMMON PROBLEMS:

We find these moldy or conducive conditions indoors:

  • Moldy window sills, from moisture condensation on glass or on metal frames.
  • Moldy bathroom or bedroom walls, more on exterior, or behind furniture.
  • Moldy, water stained, or wavy walls or ceilings below leaks.
  • Moldy attics, often on large areas under the roof, from condensation.
  • Moldy odor in basements (damp? carpet?) or in cabinets below sinks.
  • Mold or water stains with white “efflorescence” salt crystals deposited on masonry.
  • Moldy crawl spaces from poor drainage, bare soil, poor ventilation.
  • Rotted wood from slow leaks around tubs, showers, toilets, or roof eaves.

MOLD GROWTH:

We see spots or fuzzy growth on surfaces.

  • Mold spores land on surfaces everywhere, just waiting for moisture to grow.
  • Mold growth indicates excessive moisture that permits amplification.
  • Mold indoors is usually limited by water availability (also needs food & light).
  • More mold grows inside windward S & W walls near Puget Sound from rain & leaks.
  • More mold grows on the N side walls and attics near Puget Sound (away from the sun, so cooler, more condensation; and driven by the prevailing wind).
  • Mold colonies start from seedlike “spores” or fragments, and grow out rootlike threads to form circular spots, then a mat of “mycelia” or “mildew”.
  • Outdoor molds grow on living and dead matter, and in soil.

MOLD CONCERN:

We should fix moisture or mold problems, and avoid airborne mold.

  • Mold growth indicates a problem with moisture, and maybe other wood destroying organisms (WDOs) such as wood rot fungus or insects (beetles, termites, ants).
  • Breathing airborne allergenic mold particles can cause health problems.
  • Other fungi are less of an air concern: mushrooms, yeasts, rusts, smuts.

MOISTURE SOURCES:

We have moisture and water intrusion from indoors and outdoors from many sources.

CONDUCIVE CONDITIONS:

We must avoid conditions conducive to moisture, surface molds, or WDOs, such as:

  • Damp materials.
  • Moisture condensation.
  • High humidity.
  • Inadequate ventilation.

MOISTURE & MOLD INSPECTIONS:

We inspect a structure to find or evaluate if and why it might have problems.

  • Purpose: to find signs of water damage and mold growth, to guess possible sources/causes, to decide if it’s a past problem, or significant, active, and increasing.
  • Mold odor is useful evidence of damp mold, pointing to a source or a pathway.
  • Moisture can be measured within building materials using conductivity meters.
  • Water stains or rust are important flags and evidence of conducive conditions.
  • Inspectors reporting on conducive conditions in real estate transactions must have a License as a Structural Pest Inspector from the State Department of Agriculture.
  • Our inspections are limited to surface mold and conducive conditons (not a complete WDO inspection that includes wood rot or insects).
  • Wood rot fungus often has stringy white mats or “brown cubical rot”, and soft wood.

MOLD TYPES:

We find a few of the many natural molds growing indoors.

  • “Mold” includes thousands of species of filamentous mycelial fungi like mildew.
  • Molds are a normal component of house dust (less than 1%).
  • Molds are the microscopic plantlike version of mushrooms.
  • Some types grow mostly outdoors; their spores are often found indoors.
  • Mold types that grow in the wettest conditions may be worse for humans.
  • The type of mold usually does not change how we deal with it. It’s “just mold”.
  • These surface molds are not the structural wood destroying organisms (WDOs).

AIRBORNE MOLD:

  • Mold throws out spores when mature, when humidity is high enough.
  • Mold particles (spores and mycelial fragments) get airborne when disturbed.
  • Disturbing dry mold can release much of it into the breathing air.

MOLD TESTING:

We test to confirm some hypotheses we have guessed after inspection.

  • Mold odor can indicate the presence of hidden damp growth.
  • Test the air (at least 3 locations, including outdoors) to find what we are breathing.
  • Test. before/after cleanup, or for reassurance even though no mold was found.
  • Test the growth to confirm it is mold, if it is uncertain (stain?).

NEXT:  2. Mold Inspections

©2004-2016 Richard Knights, Blue Sky Testing Labs, Seattle, blueskylab@pobox.com