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Step railing leads to an apartment building with components to be defined

Understanding 20 Common Aluminum Railing Terms

  •   Posted on March 7, 2018

Working with railing can often get confusing, especially when very specific terms start to get thrown around. Superior is here to ease some of the confusion. 

While many items may appear to be basic on the surface, when you dig into them there is much more going on than meets the eye. Railing is no exception. Below we have outlined several of the common terms used regarding railing. While the focus was on terms referencing aluminum railing, all varieties of railing will use similar terminology. Stay tuned to the Superior Aluminum blog in the future for an in-depth look at more railing terminology, as well as an outline of common terms related to aluminum columns. Also, be sure to check out our list examining 12 Key Construction Terms!


1. Railing: A barrier or a fence used either for safety, style, movement assistance, or for keeping people or animals in or out of spaces. Comes in many varieties including aluminum, iron, steel, wood, and vinyl.

2. Railing System: A set of railings providing barriers, perhaps surrounding a porch, balcony, or in a divided space application.

3. Guard Rail: Railing designed to provide safety and protection; Placed in locations that protect from a long fall, or separating adjacent spaces such as a restricted area in a manufacturing facility.

4. Assist Rail: Railing designed to aid in the movement of individuals. Generally, assist rails will be found on stairways and ramps. Oftentimes referred to as handrail.  Assist rails are also attached to guard rails in many stair applications, as the guard rail height needs to be above the “grasp-able” height.

5. Top Rail: The horizontal component at the highest point of a set or a run of railing. In some instances, the top rail of a guard rail can double as an assist rail if barrier protection is not also required for the application.

6. Bottom Rail: The horizontal component closest to the ground. In general, the bottom rail is generally not looked at as a decorative portion of a railing system.

7. Post: A vertical portion of the railing system that accepts the top and bottom rail via brackets (or in the case of Superior Aluminum’s innovative pocket posts, via machined openings) to either end a railing section, allow for a turn, or add support to the middle of a railing system. Posts are most often the portion of the railing or railing system anchored to the ground.

8. Picket: Sometimes referred to as a baluster or spindle, the picket connects the top and bottom rail in spaces between posts. Pickets can be straight and simple, or decorative in a variety of ways.

Identifying several components of aluminum railing

9. Square Railing: A railing system using square components as seen above.

10. Pipe Railing: A Railing system created using round pipe as opposed to standard square components. Often used in municipal locations such as water treatment plants. Most assist rail is created from round pipe and can be viewed as a type of pipe railing.

11. Pipe Picket Railing: An advanced form of pipe railing that adds round pickets to create a full guardrail system with all the same components as a square system.

Pipe picket railing situated to assist parishioners travers stairs and enter an Ohio church

12. Cable Railing: A railing system that utilizes the same standard components as square railing, however, the pickets used to fill the middle space are replaced by horizontal cables. The cables add a more architectural look and are less of an impediment to a scenic view.

Square post railing with cable infills setup to protect from falls from an elevated outdoor area


13. Wall Plate: A relatively thick aluminum plate that allows the top and bottom rail components to more easily adapt to a wall. Creates a stronger installed system than attaching railing directly to a wall or to brick.

14. Pocket Post: An innovative system for posts accepting the top and bottom railing on level surfaces. The railing fits perfectly into pre-machined openings to eliminate bulky, unsightly brackets and fasteners

15. Screw Cover: A unique Superior Aluminum railing component that slides into the top and bottom rail to conceal all picket hardware and create a clean, streamlined finish.

16. Switchback Stair: A switchback stair is a staircase that starts in one direction and “switches back” to the other direction. In terms of railing, the term will be used to denote the purpose of a railing. For example: “Railing piece #18 is a switchback railing.”

17. Stair Stringer: The generally smooth pieces of a stair system that house the horizontal and vertical components of a stair. Often railing is attached to the stringer by using stringer mount bases.

Several components of step railing identified


18. Pre-Assembled Railing: The preferred method of railing distribution by Superior Aluminum. Simply put, this refers to railing sections being assembled off the job site (i.e. within the factory before shipping in Superior’s case) to make the installer’s job quick, painless, and professional in appearance.

19. Knocked-Down Railing (K-D): A railing distribution method popular with many organizations which favor sending all of the railing components as stand-alone items as opposed to a complete unit. Generally, lead times are decreased with this method but field fabrication adds numerous hours to the installation process.

       Click here to learn more about the difference's between pre-assembled and knocked-down railing.

20. Two-Line Railing (Three-Line, Four-Line, etc.): The number-line designation denotes how many horizontal lines of top/bottom rail are in each railing (in terms of cable railing, this only applies to non-cable horizontal components)


Illustration of the difference between two-line and three-line railing

We don't expect anyone to become a railing expert simply by reading this list...that's what we are here for! We are happy to help answer any railing questions or assist in designing your next aluminum railing project. Just give us a call at 800-548-8656 or contact us here!


Understanding 12 Key Construction Terms

Examining 15 Common Column Terms

Buy Pre-Assembled, or Fabricate On the Jobsite?