NOTE: 2018 is so 2023. The ARE 5.0 is now updated to the 2021 IBC, and so is this post! Check out 2021 IBC: Things to Know for the ARE 5.0.

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Previous version of this post below…

ARE 5.0 code questions can cover a large portion of your exams. Up to 22% of the Programming and Analysis questions. Up to 22% of the Project Planning and Design questions. And up to 14% of the Project Development and Documentation question. Everyone will go into the ARE 5.0 exams with some weaknesses, but I highly recommend that the building code NOT be one of yours!

The tough part is that there are a lot of things to know about the building code! As a primarily residential architect my experience is mostly with the International Residential Code. So before all my ARE 5.0 exams I had to spend a lot of time studying the IBC, which you can find for free right here: 2018 International Building Code. Fortunately I also had a copy of Ching's Building Code Illustrated (BCI). I think it's important to read the actual code, but BCI really helps break things down with diagrams and bullet points. After studying for, and taking those three exams, here are my Top 10 Things to Know from the 2018 IBC:

1. What's in Table 508.4?

Table 508.4 of the 2018 IBC shows the IBC Required Separation of Occupancies. This is a concept you'll see on multiple exams, both in the planning exams (PA and PPD) and in the construction/detailing exam (PDD). My recommendation for learning this is not to memorize the actual table, but memorize the number (508.4) so you can quickly find it in the provided resources on the exam. You can expect questions about determining the required separation between occupancies AND how to choose a wall system that meets those requirements. Check out this video on how to determine the required fire separation using the table.

2. Dead End Corridors

A dead-end corridor is a hallway the leads only to an exterior wall with no exit. A window does not count as an exit. The maximum distance of a dead end corridor is 20ft, though there are always exceptions, like certain occupancies and whether or not the building has sprinklers. The link takes you to Chapter 10 of the IBC, read Section 1020.4 for specifics of dead end corridors.

3. COMMON PATH OF TRAVEL

The IBC defines common path of travel as, “that portion of the exit access travel distance measured from the most remote point within a story to that point where occupants have separate and distinct access to two exits or exit access doorways.” In real words, you measure from the furthest corner in a room to the point where someone could egress two different ways. Marty Huie has a good video about Common Path of Travel. The maximum distance of the Common Path of Travel is set in the 2018 IBC Table 1006.2.1 which also has restrictions for spaces with only one exit.

4. Door Locations and Max Projection into Corridors

With a few exceptions, doors must swing in the direction of egress, meaning doors from rooms will swing out into corridors people are trying to use for egress. IBC limits the amount of this swing in Section 1005.7 Encroachment. (A lot of the things you need to know about the IBC are in Chapter 10 Means of Egress). When fully open, a door can only project 7″ into a hallway. When the door is being opened it can't reduce the width of the corridor by half. You have to account for this when placing doors, often times you will see them recessed into alcoves so that they can be fully opening and not reduce the required width of the hallway. I recommend remembering 7″ and “reduced by half”.

5. RAMP SLOPE

There used to be a ramp slope vignette on the old Building Design and Construction systems exam. That exam is now part of Project Planning and Design and Project Development and Documentation. So you may see ramp slope questions on more than one exam. You can read all about ramps in the 2015 IBC Section 1012 First, you need to define a ramp by it's slope. If it's less than 1:20 it's just a sloped surface, and doesn't require a handrail or landing. If it's steeper than that it's a ramp, and it can have a maximum slope of 1:12 or 8″ or 1″ per 12″ or 1ft per 12ft. Those are all the same things, just written in four different forms. The maximum rise is 30″, so if you have to go up more than 2.5 feet you'll need a landing mid way. That landing (and others) have to be at least as wide as the ramp and at least 60″ long. Minimum width is 36″ though this is absolute minimum and the ramp may have to be wider due to requirements of Section 1020.2

6. USE AND OCCUPANCY CLASSIFICATION

Chapter 3 Use and Occupancy Classification is where the different Occupancy Groups are defined. These are the most general classification of the use of a building, like Assembly, Business, Educational and Factory, etc. You don't need to memorize these, but it's good to understand what the general definitions of these groups implies. You also may be asked to choose an Occupancy Group based on a description of what the space is used for. In that case it would be helpful to refer to Chapter 3 to make a determination of what the best Group is.

7. ATRIUMS

Atriums are covered in 2015 IBC Section 404 and defined in Chapter 2: “An opening connecting two or more stories other than enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or other equipment, which is closed at the top and not defined as a mall. Stories, as used in this definition do not include balconies within assembly groups or mezzanines that comply with Section 505.”  They're basically saying an open space that's more than one story tall that's not obviously some kind of chase. An elevator shaft is clearly not an atrium. The biggest thing to know about atriums is the fire and smoke protection requirements. This is handled in Section 404.6 Enclosure of Atriums. With some exceptions, an atrium needs to be surrounded by a 1-hour fire barrier.

8. FIRE WALLS, BARRIERS, PARTITIONS

Speaking of Fire Barriers, it's important to understand the difference between the three primary fire resistant wall types you will encounter. The key difference is not the number of hours, but the construction of the walls with relation to the floor, roof and ceilings. Read the portions on horizontal and vertical continuity. These are all in Chapter 7 Fire and Smoke Protection Features.
Fire Walls: Fire Walls are covered in Section 706. They are required to extend from the foundation to 30 inches above the roof. Yes, all the way from the foundation to above the roof. A fire wall can be used to separate one structure into two separate buildings, as far as the code is concerned. They will be rated between 2-4 hours, depending on the Occupancy Groups. See Table 706.4
Fire Barriers: Fire Barriers are covered in Section 707. They must be built from the floor to the underside of the deck above (vertical continuity) They are used for many of the key separations, like separating occupancies, protecting exits, protecting atriums (see above) and more.
Fire Partitions: Fire Partitions are covered in…Section 708. See the pattern? These offer the least amount of protection of the three. They are generally used to corridors or other interior spaces. They must go from the floor to the underside of the deck above -OR- from the floor to a rated ceiling.

9. Mezzanines

Mezzanines are basically free space. They don't count against the floor area or stories limit, but they come with some restrictive requirements. Of course, there are exceptions, per usual code is relaxed when you add sprinklers or more exits. Keep in mind the goal of the mezzanine (per code eyes) is to allow a smaller space above, and open to, the space below. Like a reading room above a library stack and etc. Not considering exceptions, a mezzanine can be a maximum of 1/3 the area of the room it's in, and has to be open and accessible from that room (mezzanine walls are max 42″ high). These requirements are relaxed if the occupant load of the mezzanine is fewer than 10 people or there are two or more exits from the mezzanine. There are others, but these are the big two. Read more about mezzanines in the 2015 IBC Section 505.

10. Maximum building height and area

I personally feel this topic gets more than it's fair share of press. The amount of time people spend studying for, and stressing about building height and area doesn't seem to match up with how much this stuff is actually on the exams. BUT, it's good to know and even better, it got EASIER in the 2015 IBC.
Allowable Building Height: There are two height limitations, actual height in feet, and number of stories. You can now read these entirely from tables, with no calculations or formulas or adding 20 feet etc. Maximum height is in Table 504.3. Find your occupancy on the left, then choose sprinklers or no sprinklers, and read your max height directly from the table in the column that matches your construction type.
Allowable Number of Stories: This works the same as Building Height. See Table 504.4
Allowable Building Area: This is the big one. It still requires a formula, but it's less involved than it was before. See Section 506 for Allowable Building Area. To start, find your Allowable Area Factor in Table 506.2. This works the same as above, find your Occupancy on the left, then read across to find your Allowable Area Factor in the column that matches your construction type. On the ARE all this stuff should be given to you. Then you need to go to Section 506.2.1 through 506.2.4 to find your specific area increase formula. There is a slightly different formula depending on whether you are mixed-use single story, single occupancy multi-story, etc. If you have a single-occupancy multi-story building your formula will be Allowable Area = [Table Value from 506.2 * (Frontage Increase)] * Number of Stories. Frontage Increase is a whole different situation, so let's say it doesn't apply here. Your formula for total area becomes your table value multiplied by the number of stories. Easy! I have a more in-depth example in the PPD/PDD Study Questions Course. See Week 5 Question 34.

11. EXCEPTIONS

OK, bonus tip here. There are exceptions to pretty much everything I've covered above. It's good to know they're there and what their purpose is. In your studies focus on the exceptions that relate to sprinklers, exits, and number of people. Pay less attention to things like 505.2.3 Exception 4 which allows equipment platforms in Industrial facilities to be glazed on all sides. If you actually get that question on the exam and miss it because I told you don't worry about it…sorry?

12. Maximum FLoor Area per occupant load

Speaking of people, that reminds me. It's good to know how many people are allowed in different spaces. This is found in Table 1004.1.2. Find the function of your space in the left column, then find the occupant load factor in the column on the right. To find how many people can be in your space you divide the area of the space in question by the occupant load factor. Make sure you are aware of Net (actual floor area) vs Gross (total floor area including things like corridors and stairs). The space function is more specific than your Occupancy Group, so make sure to read through the list to find the one that is most accurate.

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