How to Choose the Best Double Glazing Companies Near Me Keep an eye out for accreditations if you are in the market for double-glazed windows. These include FENSA, a government-authorised scheme that monitors building regulation compliance for replacement windows. The top double-glazing firms are Everest, Anglian Home Improvements (AHI), Safestyle http://www.stes.tyc.edu.tw/xoops/modules/profile/userinfo.php?uid=1203929