Fiberglass doors and House Numbers?

Hello there. Now, I am not sure how thick your fiberglass door "skin" is. But if the fiberglass skin is thick enough, you should be able to drill and install some screws to secure the numbers. You could also possibly use a type of plastic anchor or possibly double stick tape. In my experience, sometimes the tape is the best option. See if you can contact your door supplier or the contractor who installed the door to see what they think. Also check with a hardware store or local pro in your area to see if they are familiar with installing numbers on fiberglass doors.