How to Build a Mold-Safe
Home or Commercial Building
February 14, 2005 — By Phillip
Fry
VANCOUVER, CANADA. Mold
infestation in a new home or commercial building is common. The mold
problem can cause severe health problems for occupants as well as
substantially reduce the fair market value of the structure because moldy
homes and buildings are now more difficult to sell or rent.
To build a mold-safe house
or commercial building, follow these twenty mold prevention
recommendations from Phillip Fry, Certified Mold Inspector, Certified Mold
Remediator, and author of the mold advice book Do-It-Best-Yourself Mold
Prevention, Inspection, Testing, and Remediation.
1. Prior to blueprint
drafting, obtain the advice and suggestions of a mold prevention
consultant to include the most effective water intrusion and mold
prevention strategies in building design, selection of building materials,
and construction techniques. “The key to mold control is moisture
control,” advises the U.S. Environmental Protection Agency (EPA).
2. Make sure that the
building lot and its landscaping grading are downward and away from the
building to keep rain and surface water from entering the building
foundations, basement walls, concrete floors, and crawl space areas.
3. Install a thick, high
quality moisture barrier (with no holes from negligent installation)
beneath any concrete floor slab or basement concrete floor to stop water
from wicking up from the ground into the concrete, and thus into flooring
materials and walls resting on the wet concrete.
Do not use regular plastic
sheeting as a moisture barrier because such sheeting is easily damaged in
installation, and it usually suffers physical degradation over time---thus
allowing water penetration into the concrete.
4. Add adequate amounts of
top-quality waterproofing compound into the concrete mix to transform the
entire concrete floor or slab into an effective water barrier. Also,
thoroughly waterproof the exterior of basement walls and of the building
foundations.
5. Dry thoroughly (30 days)
the concrete floors and concrete/masonry walls prior to adding wood
building components. New concrete holds thousands of pounds of water. Most
of this water usually dries to the inside of the house or building if the
wood building components are installed prior to complete concrete drying,
according to the Nova Scotia (Canada) Department of Energy.
6. Do not install plumbing
supply lines into concrete slabs or floors, wherein the lines usually
degrade and start leaking in twenty years or less. Hire the most capable
plumber to install the best quality plumbing lines, fittings, and
equipment.
Concentrate all plumbing
lines and sewer drain lines in as few areas as possible, with large, easy
access panels for the monitoring, maintenance, and repair of plumbing
components.
7. Minimize the potential
for water damage from frozen, broken pipes by insulating water supply
lines (in the attic, crawlspaces, garage, and exterior walls), protecting
exposed outdoor faucets, and sealing gaps in exterior walls.
8. Use a hidden moisture
meter to scan the ceilings, walls, and floors of all plumbing areas for
water leaks prior to building occupancy, and on a regular basis
thereafter.
9. Use steel framing
components instead of wood [delicious food for mold growth] to build the
walls, second floor, attic, and roof of the building. Although steel
framing is a little more expensive than wood, it is very affordable
long-term, especially in consideration of steel’s water damage and mold
prevention qualities, as well as fire resistance.
10. Alternatively, build
the walls out of poured concrete, concrete blocks, or insulated concrete
building components. Use adequate amounts of waterproofing compound in
both the concrete and in cement stucco interior and exterior finishes.
Build weep holes into the
exterior masonry walls. Weep holes are openings at the foundation level of
a brick or concrete block wall that allow moisture to escape from behind
and inside the wall. Do not close or block these openings.
11. If the owner or builder
uses any wood timbers, plywood, plywood substitutes, drywall,
plasterboard, and ceiling tiles, pre-inspect such cellulose-based
materials for mold growth and mold stains prior to their use. Remove the
mold completely from the materials or return the materials to the
supplier, and replace with mold-free materials. Use a moisture meter to
scan all wood for moisture content, which should not significantly exceed
16 to 17 percent.
Cellulose is the main
substance in the cell walls of plants (and thus of wood from trees), and
it is used in the manufacture of the paper backing of insulation,
artificial fibers (e.g., for carpeting and padding), and many building
materials such as drywall, plasterboard, and plywood substitutes.
12. In addition, spray all
cellulose-based building material surfaces with at least two wet sprayings
of an EPA-registered fungicide, followed with at least one coating of an
EPA-registered protective fungicidal coating. Allow the surfaces to dry
after each spray application.
13. Install a high-quality
rubber water barrier beneath the roof shingles or tiles to keep rain from
entering the building should there be degradation of, or damage to, the
shingles or tiles. Install gutters (with leaf-catching screens) that lead
to in-ground pipes that take rainwater away from the house.
14. During construction,
store all mold-vulnerable, on-site building materials off the ground and
beneath waterproof tarps or plastic sheeting to protect the materials
against rain, and thus against mold growth.
15. During rain and as a
precaution at the end of each construction day, cover the entire building
with waterproof tarps or plastic sheeting to keep rain off of the building
until the roof has been shingled, and the siding and windows have been
installed.
16. Prevent construction
defects that allow water entry into the home or building by carefully
monitoring the day-to-day construction of the structure. A
construction-savvy owner, a trained employee of the building’s architect,
or an independent physical engineer or home inspector should do this
important construction quality control monitoring. Construction defects
are an important cause of mold infestation.
17. Design the
heating/ventilating/air conditioning (hvac) system to have in its return
air duct a built-in mass media (6 inches or thicker), replaceable hepa
filter, or a top-rated electronic air cleaner to remove continually
airborne mold spores from the circulating air.
18. Install a programmable
dehumidifier into the hvac to reduce indoor humidity to a
mold-discouraging 30 to 40 percent. Do not install a moisture-increasing
humidifier. Install a humidistat-controlled exhaust fan in the attic and
any crawl space area to help keep the humidity level low in those areas.
Install exhaust fans that vent directly outdoors in the bathrooms and
kitchen.
19. Do not use wall-to-wall
carpeting because carpeting and padding are great mold food and a great
place for mold growth, viruses, bacteria, and dust mites to hide and to
multiple. Instead, for concrete floors, use ceramic tile set in cement
containing a waterproofing compound. Use colored cement with waterproofing
as the tile grout. For wood floors, install vinyl tile or linoleum. Use
washable area rugs for comfort and beauty.
20. During construction and
also upon completion prior to sale, rental, and occupancy, the building
should be inspected and mold tested all-around for mold problems by a
Certified Mold Inspector, or with do it yourself mold test kits.
For more information about
mold prevention, please visit---
http://www.moldinspector.com
http://www.certifiedmoldinspectors.com
http://www.mold.ph
http://www.moldmart.net
http://www.envirosurf.com
Contact: Phillip Fry, author
Phone: 011-63-921-352-1287
Email:
moldinspector@yahoo.com |