Call us: 1-800-366-7515

Second Best Elite Permits Logo

Elite Permits

Blogs , Videos, News & Updates

Residential versus Commercial Code

august 2022, issue 1



Written by TATIANA gUSt

Understanding the building code that applies to your project is essential; however, for people not involved in code compliance it is not as clear as it should be. I will try my best to make it simple and understandable. 

The main building codes, and the foundation for many of the state specific codes, are the International Code Council (ICC) building codes. These codes are separated into the following three categories: 

  1. Residential, 
  1. Building also known as (AKA) Commercial, and  
  1. Existing Building.  

There are a number of trade specific codes, such as plumbing or electrical or mechanical, but we are going to omit those for clarity.

Before we dive into the residential or commercial aspects, let me explain a crucial difference in the words. The word “residential” refers to the USE of a building, meaning it is for living purposes. Some examples of which can be a house, a duplex, a condo, an apartment, or a hotel. However, all of these residential USES are not regulated by the same code. Some are regulated by the residential code and others by the commercial code. 

The “Residential” version includes all the requirements for building, mechanical, electrical, gas and plumbing (MEP) within its code, while the building, aka Commercial, has a separate code that is more specific for each of the additional disciplines, hence the number of other books as mentioned previously.

Single Family home

Single Family



To put in simple words, projects that fall under the residential code can use a single book for the design, while all other projects have a number of books that need to be consulted while the building is being designed. 

Let’s talk about understanding which code applies when. The main intent of the code is to protect property and its occupants.

Therefore, the buildings with the least risk are the smaller ones where you are familiar with the surroundings. Can you think of a small building that you know how to get in and out with your eyes closed? Does your own house come to mind? That’s correct. A house is the least risky due to the limited number of occupants, the limited size, and the fact that most people know their homes very well (we will talk about the exceptions later). The risk is manageable.  

Now think about what happens when you put multiple living units next to each other. For example, condos or apartments. The risk becomes larger, because more people may be impacted in an emergency, or more property can be damaged just by being next to each other. Now, let’s add another variable. You have several of these living spaces that are next to each other, but you are not very familiar with the surroundings because you just stopped by to spend the night, like with a hotel. The risk becomes even greater, because in an emergency, the occupants may or may not know how to navigate the building to reach safety.  

So, the code regulators understanding the different instances created a separate code which allows smaller, more manageable buildings to have different rules than the ones with a larger risk. Hence the different Residential and Commercial codes.  

What can be designed under the Residential code? The Residential code applies to single family homes, duplexes, and townhomes that are three stories or less. This is very specific, because if the building becomes taller, then there is additional risk.  

codes and books

More risk = more protection.  

Therefore, for those large homes that are three stories over parking, the applicable code becomes the Commercial code, and they must adhere to a different set of standards.  

Everything else that does not fall under the Residential code must be designed with the Commercial code.  

To make it easier for everyone:  

Residential ==> Single family, duplexes, or townhomes; up to three stories 

Commercial ==> Everything else 

Let me know if you have additional questions about the building codes, follow us for more, and share our blog! 

Share this Post

Related Articles

home vs building inspector

Understanding the differences between Building Inspectors and Home Inspectors

Building inspectors and home inspectors may have similar backgrounds, but they serve different roles. A building inspector works for a municipal entity or private company and inspects buildings during the construction process, whereas a home inspector is usually an independent contractor hired by buyers to evaluate existing buildings for safety and soundness. In this blog, we’ll delve deeper into the differences between the two professions.

Read More »
What inspectors look for at final inspection.

What inspectors look for at final inspection.

Today we will be discussing about inspections related to a building permit from a building code point of view. As we have discussed in other blogs, there are different departments that also review and inspect as part of the building process. There could be other inspections such as final site inspections, final fire inspection, or final health inspection, etc.

Read More »
building codes

Base Building Codes

Base Building Codes

As a code consulting professional, I like to explain how the state-specific codes are developed and how to use them.

I live in the beautiful state of Florida, and before 2002 there were building codes in the state, but pretty much each jurisdiction had their own codes and local requirements regarding the building portion of the code.

Read More »
what is a storm surge

Understanding Storm Surge

With another storm on the horizon, I want to take this time to explain storm surges:
The news in their desire to provide information, often do so in a context that is not clear for everyone. I have been working in construction and everything associated to the building codes for over 18 years, I’m accustomed to the language and what it meant, but never thought about explaining it to the people closest to me.

Read More »

Online Resources for Codes

Today I want to share some helpful information about what is available to anyone online. In our last blog we talked about the zoning codes and the building codes, so I decided to provide helpful links here to the resources for those codes. I will start with the simple single statewide code, the Florida Building Code. This link allows you to see all the building codes which includes about eight books, all of which you can electronically search and read about what applies under each category.

Read More »
Elite Permit Favorites
Social Media

Like Us On Facebook

Stay in Touch

Subscribe to our newsletter for more updates

icon About
Exposure represents the adjustments due the characteristics of the terrain surrounding the building.

Exposure B.For buildings with a mean roof height of less than or equal to 30 feet (9144 mm), Exposure B shall apply where the ground surface roughness, as defined by Surface Roughness B, prevails in the upwind direction for a distance of at least 1,500 feet (457 m). For buildings with a mean roof height greater than 30 feet (9144 mm), Exposure B shall apply where Surface Roughness B prevails in the upwind direction for a distance of at least 2,600 feet (792 m) or 20 times the height of the building, whichever is greater.

Exposure C.Exposure C shall apply for all cases where Exposure B or D does not apply.

Exposure D.Exposure D shall apply where the ground surface roughness, as defined by Surface Roughness D, prevails in the upwind direction for a distance of at least 5,000 feet (1524 m) or 20 times the height of the building, whichever is greater. Exposure D shall also apply where the ground surface roughness immediately upwind of the site is B or C, and the site is within a distance of 600 feet (183 m) or 20 times the building height, whichever is greater, from an Exposure D condition as defined in the previous sentence.