Another HADD member supplied a link to a site that has a good video showing how window flashing is properly installed, (whether you buy the company's brand or not). http://www.graceathome.com/pages/flashing.htm MANY new homes do not have any window flashing at all, virtually guaranteeing leaks, rot, and costly repairs for the home buyer. In many areas code required materials like flashing and roofing felt are omitted and this is allowed by building inspection departments. A person really has to educate themselves and watch like a hawk.