IS NH ATTIC MOLD A PROBLEM ? – Is attic mold in NH a health risk or indoor air quality problem?
Toxic attic mold NH: Toxic mold should be removed, although the ease of movement of mold spores from an attic down into a living area varies widely from building to building.
Unknown NH attic mold: You may occasionally find mold growing on the attic side of a ceilings drywall, specifically if there were roof leaks or areas of ice dam leaks found at a buildings eaves.
Fiberglass insulation is mold resistant, but the paper backing that holds it on is not!! We pull back the fiberglass insulation to expose potential areas of mold growth. What about the white mold-like stuff visible on the rafters? Is that mold? If it is mold, is it a problem?
Our response is, it depends. In addition to mold testing to see what type of mold it is (presuming there is a large area of it), We Kill Molds mold inspection would also evaluate the likelihood of particles traveling from your NH attic to your living space before deciding on an appropriate approach to this moldy attic.
MOLD FACT: It is simply not true that all NH attic mold is toxic. Nor is it true that all NH attic mold is even harmful.
MOLD FACT: Not all attic mold in New Hampshire needs to be remediated or removed.Not all attic mold is necessarily going to enter your living space or be an issue for the buildings residents.
It is however important to note that attic mold in a New Hampshire home indicates moist conditions and possible leaks and therefore further mold inspections and mold tests are in order.
Here is some information about airflow in NH buildings and the chances that attic mold spores will make their way from your attic into your living quarters.
• Air and particle movement in buildings tends to be up and out: i.e lowest floors to the upper floors to the attic.
• Mold spore movement downwards from an attic into a building is difficult and somewhat unlikely.
• Attic mold is far less likely to be the significant source of a mold problem in a New Hampshire home than moldy lower areas such as crawl spaces or basements.
• Exceptions to this upwards movement of indoor air flow do occur :
• Attic or whole house fans: When a whole house vent fan is used and the attic venting is inadequate – resulting in a pressurized attic. When the fan is operated, attic particulates, including mold, insect allergens, rodent fecal matter, mite fecal matter, bird droppings, dust, particles may be blown downwards into the living area or into attic-mounted HVAC equipment.
• Moldy NH attic knee wall areas: A moldy attic kneewall space adjacent to a bedroom on the upper floor of a cape cod or similar house.
• Pine roof sheathing: Older NH homes using pine boards as roof sheathing use a material which more readily supports growth of Aspergillus and Trichoderma viride as well as other more problematic molds than found in plywood sheathed roofs.
Is Mold sealed within building cavities hazardous?
When NH attics or insulation contain a large reservoir of potentially toxic or allergenic mold, & if the attic area was not readily accessible (if for instance the space is too small to enter) then it may be necessary to remove a portion of the roof to give access for mold remediation,especially if there is evidence of the problem mold found in the living area.
While some experts claim there is no relevant toxic mold spore movement from these sealed cavities into living space, and therefore mold found in these building cavities isn’t problematic, our NH mold inspections and test results prove that in at least some buildings, certain easily airborne mold species such as Aspergillus may make their way throughout the structure and may be still be a health concern for some building occupants.
The movement of mold-spore laden air in and out of building cavities and between building areas is not reliably predicable from a visual inspection, nor from simple air tests.
Simply turning a building fan on or off, opening or closing a window, turning up the thermostat, and many other conditions can change how air is moving in buildings.
Air Does Not Always Move Up and Out of a Structure as Building Science Would Suggest
Finally, building air sometimes moves contrary to what building science would lead us to expect. For example we assume that warm air rises up through buildings, passing out through roof ventilation. But direct measurement in some buildings has shown that warm air (including from a moldy attic) can sometimes flow downwards into the occupied space. Two examples that we have frequently observed in the field:
1. Air conditioning the upper floors of a hot building can cause a sufficient volume of chilled air to flow downwards (by gravity, through stairwells) at a rate that draws warm air down into the occupied space from an attic.
2. Use of a ceiling-mounted whole house fan to attempt to exhaust hot building air, combined with inadequate exit ventilation out through the attic or roof space can pressurize the building attic, blowing attic air (possibly warm or moldy) downwards into some building areas, air passing through openings cut for ceiling light fixtures, wiring, plumbing, or duct work.