How Deep Should a Bollard Go?

Bollards, sometimes incorrectly known as bollard fencing, are an effective barrier to vehicles while still leaving the area open to pedestrian traffic. This makes them an attractive option in busy urban areas, where space can be limited, and it’s a common alternative to certain fencing systems. In places like Phoenix, where vehicle congestion is common, properly installed bollards can help protect storefronts, pedestrians, and property from accidental impact.

However, to be an effective barrier to vehicular traffic and protect people or property, it’s important to design bollards properly. Let’s take a closer look at how deep bollards should go.

Consult an Engineer

There’s always some level of legal liability whenever there’s a risk of property damage or injury related to bollards. If there’s any chance that a vehicle could seriously injure someone or cause substantial property damage, consulting a professional engineer is strongly recommended. Engineers can calculate the force that a vehicular impact would create and can determine the appropriate specification for steel dimension, footing size, and foundation depth.

This is especially relevant in places with specific building codes or legislation regarding safety barriers, such as the requirements in many Arizona municipalities. Never attempt to cut corners on bollard design to save money. If something goes wrong, you could be liable for injury or damage.

Consider Crash-Rated Bollards

If you need additional impact protection or want to be certain about stopping power, you might want to consider crash-rated bollards. These bollards (or bollard fencing systems) are rigorously tested under actual vehicular impact conditions to confirm that they can withstand a specific level of force. Different regions have varied crash rating systems, so make sure you choose a design that aligns with local codes and regulations.

Be sure to follow the manufacturer’s installation instructions whenever you use crash-rated bollards, and confirm that your site conditions align with the product’s specifications. If the soil or foundation conditions on your site change significantly from what the manufacturer tested, you may still need an engineer to verify that the bollard system will perform as intended.

At Least As Deep as They Are Tall

If you’re not installing bollards meant to protect against high-impact collisions, a standard commercial-grade bollard may be sufficient. These are typically substantial steel pipes filled with concrete, installed in a concrete footing and painted a visible color such as yellow or orange. Precast concrete bollards are another possibility, although they can be more susceptible to damage from repeated or forceful impacts.

A general rule of thumb is to install bollards at least as deep as they are tall. This helps create a solid foundation, ensuring a sufficient amount of the bollard is below ground to resist the forces of a vehicle strike. In the Phoenix, where soil conditions can vary, it’s important to confirm that footing depth is appropriate for the site’s composition. Base plating bollards isn’t commonly recommended unless there’s little risk of high-impact collisions or the base plate has been specified and tested by an engineer.

Western Fence is experienced with commercial and industrial security solutions in the Phoenix area. If you’re considering bollard installation or looking for a secure, durable option for your property, learn more about our Phoenix bollard installation services.