Shot simultaneously on 35 mm film and high-definition video. Tommy Wiseau was confused about the differences between the formats, so he used both cameras on the same mount. He also purchased the cameras, instead of renting them as film productions usually do.
According to Juliette Danielle, when Tommy Wiseau said the line "In a few minutes, bitch," everyone on the set began laughing at him. Wiseau came out of the bathroom and demanded to know what was so funny.
After filming the first love scene, Wiseau decided to write in a second love scene, but the actress playing Lisa was uncomfortable. As a compromise, the second love scene between Johnny and Lisa was created from unused shots from the first love scene (which is why the candles are already lit when they arrive).
Tommy Wiseau esoterically addressed several fan questions in a special Q&A feature filmed for the DVD release. Among these are "Why is it called 'The Room'?" (to which Wiseau replies that the title is meant to evoke a safe place for viewers) and "Why is everyone playing football in tuxedos and standing only three feet apart?" (which Wiseau doesn't answer except to say that football is fun and that playing it without protective gear is a challenge).
Kyle Vogt had to quit the film because of a prior acting commitment. He told Tommy Wiseau about it months prior, though Tommy assured him filming would be a wrap by that time. That explains why his character, Peter, is not at the party at the end. Peter's lines were given to Greg Ellery, who unexpectedly shows up at Johnny's birthday party. One of Peter's last lines is "That's it; I'm done."
In an interview with Entertainment Weekly, script supervisor Sandy Schklair claimed that it was he who actually handled the direction of the film. According to Schklair, Wiseau was too busy with his acting duties leaving Schklair to do the directing. Schklair's claim was corroborated in the article by a cast member who remained anonymous. Wiseau has denied the claim.
After a very limited theatrical run, the film has become popular as a "midnight movie," with a cult following. Audience members dress up as the characters, throw plastic spoons at the screen, and toss footballs to each other. Tommy Wiseau attends many screenings, and holds Q&A sessions with the audience.
Greg Sestero was originally hired as a line producer. But when the original actor cast as Mark quit the film, Wiseau persuaded Sestero to take over the role. According to Sestero, he at first turned the role down because the love scene made him uncomfortable. He explains that this is why he is wearing jeans during that scene.
Much of the furniture and decor for the main "room" set was a complete display room taken from the window of a thrift shop. The glass-top television table supported by white pillars belonged to Wiseau.