You can add interest and beauty to your front entry door, not to mention more sunlight to your entryway by installing a window in the door. A solid wooden door, especially one with panels, may be a simpler project than installing a window in a metal or fiberglass doors. Your local builder supply, lumber yard or home improvement center can supply you with everything you need.
Types of Doors
Solid opaque entry doors by code are required to meet certain standards for durability and strength. Wooden doors will have a solid core. Metal doors may be thin sheets overlaid over wooden or metal frames and usually are filled with insulation. Fiberglass doors are molded sheets laid over a polyurethane foam core. The type of door you are modifying will determine the type, size and location of any windows you install.
You will need to set up a pair of saw horses. Remove the pins from the door hinges, remove the door and lay it on top of the saw horses. Measure and mark the area you will remove to receive the window. If you're limited to a certain size opening, go visit your window supplier and see if they offer a window kit that fits. Solid flat front fiberglass or wooden doors will allow you to adjust the opening to fit any standard door window kits. For metal doors, you'll have to figure out if there's a wooden frame underneath and cut the window to fit inside the framework without weakening the structure. For odd sized openings, you'll have to custom fit the glass and frame mouldings.
Choose glass that is tempered, shatter resistant and meets building codes. Double paned or insulated glass is a good idea too to lower energy bills. The glass must be cut 1/8 inch smaller on all four sides than the opening. Beveled or stained glass windows add interest to the front door and can be custom cut to fit carved panel openings.
Cutting the Opening
If installing a kit follow instructions. If you're installing custom glass panels, cut the opening 1/8 inch wider all around than the panel. This allows the door to expand and contract seasonally without breaking the glass. Drill a pilot hole large enough to insert a reciprocating saw blade and carefully cut out the opening.
Select moulding you like that fits the opening you've cut and that's deep enough so that the two sides leave the right size gap for the glass. Glue the molding or nail it into place on one side of the door. Once one side is secured, flip the door over and lay a bead of caulk around the inside of the moulding. Carefully lay the glass in place, add another bead of caulk around the inside of the glass and frame around the hole on the other side with the decorative moulding.
Once the glass is in place, you can still add decorative touches. You can lay a custom made stained glass or beveled glass panel over the top of a plain insulated pane and hold it in place with decorative moulding or caulk. If you allow for the extra panel when sizing the moulding, you can lay the decorative panel in place before adding the back side. It's better to hold the panel in with moulding than with caulk because the glass needs to resist the impact of occasionally slammed doors.