Build panels and calculate prices for glass block Panel Builder prevents costly errors when figuring prices for glass block windows and cuts your billing time in half. Odd size windows can take time to layout, especially for beginners. Panel Builder makes working with glass block fast and easy. Build solid or vented glass block panels. Position the vent where you want it. Add up to 5 different size vents to custom panels. Add dryer blocks and change panel layouts. Over one hundred different sizes of vents to choose from. Set password protection for block and vent prices as well as accounts.