The glass block window panel sits on the block or concrete wall and is held in place with mortar and caulk. When it comes to basement windows, there’s nothing more practical than glass block ...

The small 2- to 4-inch glass blocks are constructed like a brick wall using mortar and sealant and can serve as windows and privacy walls in bathrooms, entrances, basements, and bedrooms.

Dear Jim: I am concerned about the security and efficiency of some of my old single-pane first-floor windows. I think glass block windows would be more secure.

Glass block windows across Pittsburgh. If you’ve been in Pittsburgh for more than a few hours, you’ve definitely seen them.