Can I install a peephole in a fiberglass entry door?

Yes, you can install a peephole in a fiberglass entry door — it's one of the more DIY-friendly door modifications and doesn't require professional help in most cases.

What You'll Need

A standard peephole kit from any hardware store will work. You'll need a drill with a hole saw or spade bit sized to match your peephole diameter (typically 1/2" to 9/16" for most standard peepholes). Make sure the peephole barrel length matches your door thickness — most fiberglass entry doors are 1-3/4" thick, so confirm this before purchasing.

Drilling Into Fiberglass

Fiberglass doors drill similarly to wood, but there are a couple of things to keep in mind. Use a sharp bit and drill at a moderate speed — too fast can cause the fiberglass skin to crack or chip around the hole. Placing a piece of masking tape over the drill point on both sides of the door helps prevent chipping and gives you a cleaner finish.

Placement

Standard peephole height is 58" from the floor, which works for most adults. If you have family members of varying heights, wide-angle peepholes (offering 180° or 200° viewing angles) are a good option and widely available. Position it centered on the door, away from any decorative glass panels or structural reinforcement areas.

One Caution

If your fiberglass door has a foam or composite core with internal reinforcement ribs, drilling in the wrong spot can hit a rib and complicate the install. Check your door manufacturer's documentation if available, or probe gently with a thin nail first.

This is a straightforward weekend project for most homeowners. If you're ever unsure about your specific door construction, Ottawa Window Pros is happy to answer questions — or if you're looking at a full door upgrade, we offer free consultations on fiberglass entry door installations.