Bill Stafford who played Mr. Rudolph is a traveling evangelist who was visiting for a church event. All his scenes were filmed the same day, and it was after Kirk Cameron had left, they never actually saw each other.
Almost all locations used in the film (firehouse, hospital, houses etc.) were existing places that were donated for filming. The only area constructed specifically for the film was the area where Caleb crawls during the house fire, which was not part of the actual house.
When Michael tells Caleb that Catherine is in the fire truck bay, he is wearing a shirt with pointed pocket flaps. Once Caleb arrives to the fire truck bay, he is wearing a shirt with straight pocket flaps.
When Caleb's father tells him that Caleb's mother was the one who did the Love Dare, the two men are on a long path in the middle of the woods, at least several hundred yards from Caleb's house. Caleb, an athletic fireman, immediately sprints back to his house to apologize to his mother. However, his father, an old man nearly twice his age, arrives at the house about 10 seconds behind him and is not even out of breath.
The following FAQ entries may contain spoilers. Only the biggest ones (if any) will be covered with spoiler tags. Spoiler tags have been used sparingly in order to make the page more readable.
Q
Is "Fireproof" based on a book?
A
No. Fireproof is based on a screenplay co-written by film-makers Stephen and Alex Kendrick (who also directed the movie). However, the book featured in the movie, The Love Dare by the Kendricks has also been released to coincide with the movie's release in 2008. A novelization of Fireproof by Eric Wilson was released in 2008.
Q
Are all the actors real-life Christians?
A
Yes. Kirk Cameron is an Evangelical Christian, and the cast is made up of church volunteers.