A door lite is a glass panel set inside a door. Each panel is considered a separate lite, even if they’re arranged to form a larger glass structure.
A real lite is built into the door, though you can also find ‘faux’ lites, which are attached to the glass using snap-in grilles. The use of these devices substantially lowers the cost of manufacture, and in turn the door. This makes them a tempting option for homeowners on a budget.
Grilles of this sort come in a range of different types, and can be arranged vertically or horizontally to suit your existing windows.
More elaborate patterns of lites can only be created if the glass is built into the door. If budget isn’t so much of a concern, it makes sense to invest in doors with real lites rather than fake ones (this is especially true when you come to sell, since it will up your property’s ‘kerb appeal’).
A sidelite, on the other hand, is a window that’s designed to sit alongside a door. They’re used to create the illusion of size, and allow natural light into the home.
On the downside, sidelites (as well as door lites, if they’re positioned low enough) allow those outside to see into the property. Stained or privacy glass can mitigate these concerns, as can curtains or blinds.
Transom windows are a relation of sidelites, but instead of sitting alongside the door, they sit just above it. Transom windows are a common feature in Victorian and Edwardian houses with higher ceilings.
The picture below shows a door with door lites, sidelites, and a transom window.
