"Easy Air" is a passive vent which is incorporated into the window system. It can be retrofitted to existing homes which suffer from lack of natural ventilation or incorporated in the windows at the time of manufacture. Using the window system gives instant access to the outside of the house and requires only one tradesman (a glazier) to install. To be fully successful one vent exceeding 600mm long needs to be installed in each room of the house. Fresh dry air enters the home on the windy side of the house while stale, polluted and moisture laden air exits on the sheltered side. The vent also incorporates a fine insect screen to prevent the entry of unwanted pests such as flies and mosquitoes. The system allows continual secure ventilation even when the home is locked and empty. The product has been Telarc tested and complies with NZ Window Standard 4211.