Because so many house fires start in the garage, due to the numerous flammables stored there—not the least of which is a car gas tank—the building code requires a fire-resistant barrier between an attached garage and the house. The building code uses the words “fire separation” instead of “fire rated” for it’s standards for the construction of walls, ceiling, and door to the home.

    So the fire separation standard for garage door to house gives you three options:

• Solid wood door not less than 1-3/8” thick.
• Steel door, with a solid of honeycomb core, not less than 1-3/8” thick.
• A door with a 20-minute fire-rating.

    Also, the door cannot open directly onto a room used for sleeping purposes (bedroom). Here are examples we see during our inspections of when the safety standard has been breached:

•  An opening has been cut into the bottom of an otherwise acceptable door to install a pet door.
•  A steel door with a fixed glass panel that is not fire-rated has been installed. We check the “bug” on the glass and it is usually safety glass, but have yet to find one with glass that is fire-rated. The door shown below is an example. 
• A remodeler doing a “flip” house changes out all the doors in the home to update the interior, and replaces the old door to the garage with a hollow-core interior door.

       Also, we recommend that the door between garage and residence be equipped with a self-closing device, although no longer required by the IRC and FBC. Every few years there is a news story in Florida about someone, usually an older person, asphyxiated by carbon monoxide fumes because they left the door to garage open with their car running while they rushed into the house on a quick errand, then became distracted and stayed in the house, while forgetting to turn off the car or close the door.

    For details on the full requirements for garage fire separation, go to our blog post What are the code requirements for fire separation between an attached garage and the house?

• • • • • • • • • • • • • • • • • • • • • • • • • • • 

  To learn more about doors and windows, see these other blog posts:

• What causes sweating (condensation) on the inside of windows in the winter? 

• Is every exterior door of a house required to have a landing outside? 

• What are the small slots at the bottom of the outside of my window? 

• Why does condensation form on the outside of some windows and not others in the morning? 

• Why is the garage door track a white tube? 

• What is the raised metal plate on the floor under the garage door?

• Why do I have to hold down the button to close the garage door? 

• How can I tell if a window or glass door is safety glass? 

• What are the code requirements for safety tempered glass for doors?• 

• Should a front door swing in or out? 

• How many exit doors are required for a house?

• How many exit doors are required for a mobile/manufactured home? 

• Are openable windows required to have window screens? Will windows with no screens pass a home inspection? 

• Can a bedroom door open into the garage?

• What are the building code requirements for a door from the garage to the house?

• What is "low-E" window glass? 

• What does ANSI 297.1 on glass mean?

• Why is a double cylinder deadbolt lock on an exterior door a safety hazard? 

• How can I check my garage door to make sure it is safe?  

• What is an egress window?

• Does a home inspector test all the windows and doors in a home? 

• How difficult is it to change a window to french doors or a sliding glass door?

• How do you determine if a door is left-handed or right-handed?

• Why are window security bars dangerous? 

• What are the common problems you find inspecting windows?

• What is causing a foggy haze on my windows? 

• What do those numbers on the manufacturer's stickers in new windows mean?

• What does a home inspector check on an electric garage door? 

• What is the tempered label on glass at windows and sliding glass doors called?

• Why is pressure washing double pane windows an expensive mistake? 

• How can I tell if a window or sliding glass door is double or triple pane (insulated) glass?

• Do I need to have two exterior exit doors in my house? 

• When is safety glass required for windows at stairs and stair landings?

   Visit our DOORS AND WINDOWS page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.