increasingly houses are being built with basements that are NOT intended to be finished however homeowners are laying carpets on concrete floors and wood paneling and drywall is nailed to studs against damp concrete in rooms with poor ventilation
	insulation should not be applied to concrete basement walls in new homes for at least 2 years to allow the concrete to fully dry.
	the growing number of poorly performed soffit repairs where continuous soffit vents made of vinyl or aluminum are being installed over top of original wood soffits. Unless the original wood vents ports are substantially widened, they aren't large enough to allow enough air through to the attic. Resulting rot in the attics of homes is alarming.
	attic insulation blocks soffit ventilation ports. In winter the blocked soffit vents prevent warm moist air moving up the home's interior wall cavity from escaping, and, conversely, in the summer the insulation acts as a solar collector, causing heat build up in the attic. In both cases ventilation is prevented, resulting in increased humidity and condensation levels.  Conditions are then ripe for the growth of mould.
	current building codes require that new home foundations be insulated and a vapor barrier applied on the inside of exterior walls between the framing and the drywall to the frost line (about four feet deep below grade in most regions). There can be too much moisture still in the concrete which will cause mould to breed in the insulation. Mould can grow on fibreglass insulation as well as concrete foundations.

If you think that you have mould in your home, due to the presence of what appear to be dark stains, you can test the stain.

	dab the stain with a drop or two of chlorine bleach
	if the stain's colour disappears or changes, the stain is probably mould
	if the stain colour does not disappear or change, it is most likely not mould

If the stain is mould, the best method of dealing with it is as follows:

	all contaminated materials must be removed
	if not severely contaminated, studs and plaster can often be cleaned with bleach
	contaminated wood paneling or drywall that contain paper coatings should be removed

If the mould has been addressed but returns, there is an additional problem that must be discovered.

	if the mould returns at the bottom of a basement wall, the exterior foundation wall my be leaking
	a waterproofing membrane is required on the exterior of the foundation walls. This will require excavation around the foundation.

There are preventative measures that can be taken to deter the growth of mould in homes.

	People living in well insulated, air-tight houses over 1,800 square feet in size might consider purchasing a heat recovery ventilator, also known as an air-to-air exchanger, to ensure a fresh air supply.
	In smaller homes, where HRV's are not efficient, it is imperative that cardboard boxes, books and firewood be removed from basements. Items like these attract moisture and can cut off a room's air circulation.
	Remove all carpets laid directly on concrete floors.
	Change the filter of the forced-air furnace every four to six weeks.
	Clean the dust pan at the bottom of the refrigerator regularly.
	If building a new home or an addition, install closets on interior, not exterior walls.
	Do not overstuff closets and leave closet doors open, if not louvered, to ensure proper air flow.
	Do not make the bed first thing in the morning. Simply throw back the bedding to the foot of the bed and let the bed air for at least two hours. Body moisture in the bedding can elevate the humidity to a level where mould can grow.
	In the bathroom, make sure that the fan works ( by placing a piece of toilet paper over the vent) and ensure the fan vents to the outside, not the attic or wall cavity.
	During hot humid spells do not open windows, especially in basements. Install a dehumidifier when the humidity in the basement is over 50%.
	On colder winter days the window condensation should be cleaned up. As condensation is systematic of other problems, condensation that persists should be investigated thoroughly.
	Loose eaves troughs, missing downspouts, and improper grading around foundations all are breeding grounds for mould.
	Soffit and roof vents should be clear of debris to ensure proper attic ventilation.
	Clean eaves troughs in the fall to prevent ice backing up and under shingles, causing potential water problems later in the attic.
	Downspouts should be cleaned in the spring and directed away from the house.
	Do annual checks of flashing and sealants used around chimneys, plumbing stacks and other roof objects.