||That "Sick House" symptoms develop because the house literally can't breathe. As a result, it gets congested with internal pollutants or Volatile Organic Compounds (VOCs). Common sources of pollutants (VOCs) in the home are adhesives, upholstery, carpets, furnace exhausts, fireplaces, pressed wood cabinets & cupboards. VELUX venting skylights allow your house to breath!
Often described as that pleasant, "new smell," VOCs can be harmful. Short-term exposure to VOCs can cause headaches, nausea and irritate eyes, throat and nose. New houses are insulated and sealed so well that no fresh air enters in. Moisture builds up but can't escape and that makes a perfect breeding ground for mold.
Sources: Hometime and EPA