Yes, you need a building permit to convert a carport into a garage. The main reason is that an attached carport that becomes a garage comes under a cluster of code safety standards that are not required for a carport. The most significant is that the walls and ceiling areas that are common with the house must be continuous 1/2” drywall, or equivalent for fire resistance, and not compromised by any openings. This also means that a window from the house into the former carport is no longer acceptable. Some other code requirements are:

•• Door to house must be solid wood, or other door with minimum 20-minute fire resistance. No doggie door cut into it.

•• Garage must have a minimum of one GFCI-protected receptacle outlet. 

•• Must have at least one wall-switch controlled light.

•• If the vehicle garage door has an electric opener, the control buttons must be located within clear sight of the door and high enough to be out of reach of small children.

•• The floor should slope towards the vehicle garage door.

    Also, when you sell the home, some buyers and jurisdictions now expect proof of closed-out permits for any additions or improvements to a home in order to close a residential real estate sale. So having one is an asset.

    See our other articles What is the difference between a carport and a garage? and What are the code requirements for fire separation between an attached garage and the house? and What is the minimum slope for a garage floor slab? and Can a bedroom door open into the garage?

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And here’s links to some more blog posts about GARAGES AND CARPORTS:

• Why is a garage floor sloped?   

• Why is my garage ceiling sagging? 

• Why are there score line grooves in the concrete floor of the garage? 

• What are the common problems when a homeowner converts a garage to conditioned living space, such as a family room?
 
• Does an attached garage that is only used for storage or as a workshop, and not for parking a car, still have to comply with building code requirements for a garage?

• How far apart should electric receptacle outlets be placed in a garage? 

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

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

• How can I tell if cracks in the garage floor are a problem or not? 

• Why can't I use my home's central air conditioning system to cool the garage? 

• When were GFCI receptacle outlets first required in the garage?

• Why are most pull-down attic ladders not approved by building code for installation in a garage? 

• Is a ceiling receptacle outlet for a garage door opener required to be GFCI protected? 

• Can you run exposed NM-cable (Romex) in a garage?  

• What causes a garage floor to crack?

• What is the difference between an attached and detached garage? 

• What is code for the fire rating for garage walls?

• Is an attached garage required to have a door to the house or exterior?

• How can I make my garage cooler in the Florida heat? 

• Does a garage door opener need its own separate dedicated circuit?

• Is a ceiling required in a garage by code?