The requirement to have house address numbers is not part of the building code, but is almost universally required by municipal ordinances. Each city or county has a slightly different standard, but their intentions are the same: that your house numbers be clearly visible from the street so that the police, paramedics or a fire engine responding to your 911 emergency call can locate the right house.
The numbers do not have to be on the house itself. They can be on a mailbox, fence, or post in front of the home. The minimum height of the numbers in City of Gulf Breeze is three inches, and in Santa Rosa County it’s four inches. There are also typically specifications on the minimum width of the stroke of each number and that there be sufficient contrast between the numbers and the background for them to be easily readable.
All of this may seem like another example of government’s intrusion on the right of a private citizen to use their own property without interference...until your spouse has a heart attack in the middle of the night and an emergency paramedic van goes screaming by the house, then has to turn around and double back, using a searchlight to try to find your house number.
Also, a common problem that emergency responders have in locating a house is that the numbers are there but have been obscured by foliage growth over time, like in the photo at the top of the page.
Here’s an excerpt from the City of Gulf Breeze ordinance:
Sec. 23-30. Posting of numbers.
New and existing buildings shall have approved address numbers placed in a position to be plainly legible and visible from the street or road fronting the property, whether or not mail is delivered to such building or property. These numbers shall contrast with their background. Address numbers shall be Arabic numerals or alphabet letters. It shall be the duty of the owners of each building in the incorporated area to post the assigned building number on the property in the following manner:
(1) The building (address) number shall be affixed to the front of the building, or to a separate structure in front of the building (such as mailbox, post, wall, fence, etc.), in such a manner so as to be clearly visible and legible from the public or private way on which the building fronts.
(3) The numerals shall be of a contrasting color with the immediate background of the building or structure on which such numerals are affixed.