Having your own washer and dryer in your home is a great convenience, but improperly installed, they could actually do damage to your home. Of course, most would consider the washer a greater risk, but when it comes to how the dryer exhaust is set up, there could actually be a hidden problem that could pose a problem.
Whenever you dry a load of laundry through your dryer, there is about a gallon of moisture that comes out through the vent. If this was to be released inside of your home, it could lead to a number of problems, such as mold growth. You want to make sure that the exhaust from the dryer is vented outside. To prevent the air from being brought back into your home, the vent should be at least 3 feet away from doors and windows and at least 10 feet from an air conditioner.
To prevent lint from building up inside of the vent and be a fire-hazard, your duct should be horizontal, straight and as short as possible. This will also allow your dryer to run more efficiently.