When are Vehicle Barriers Required for Parking Lot

[RFreund]

When are Vehicle Barriers specifically required for a parking lot (commercial building)? I suppose I'm looking for answers based on using the IBC (if that applies) or really any code just out of curiosity.

EIT

http://www.HowToEngineer.com

 

[Twinkie]

What do you mean by a barrier?

Bumper block curb? Bollards around the building? Homeland Security type stuff?

 

[ACtrafficengr]

Or are they fall protection barriers for dropoffs adjacent to the parking lot? In that case, would curb or wheel stops and a handrail be enough?

Also, can we assume the typical parking lot mix of passenger cars, light trucks and pedestrians moving at low speed?

 

[msquared48]

When the boss's daughter is taking driver's ed...

Mike McCann, PE, SE (WA)

 

[RFreund]

Good questions and I'll try to clarify.

Well the specific site is a car dealership and they have retaining walls supporting the parking lot pavement. Some walls are 10' high, some are 1' high. They all have drainage curbs but no bumpers. At what elevation difference do these require a vehicle barrier? I say vehicle barrier as that is how it is defined in IBC. It is probably more common to say guardrail but IBC refers to Guards in a more general term (i.e. for pedestrians, handrails, guardrails, etc.).

In general though for commercial retail parking lots if this situation were to occur at what height is a vehicle barrier (guardrail) required?

I believe IBC uses 30" grade difference for "handrails"

Thanks Again!

EIT

http://www.HowToEngineer.com

 

[dhengr]

RFreund:
What does the IBC say about barriers in multi-level parking structures? They all have barriers of one sort or another, not just small height drainage curbs at the exterior edges. And still, you see pictures, from time to time, of a car cantilevered precariously from a sixth fl. edge. As much as anything I suppose it has to do with what damage can be done, either to the driver or the general public on a sidewalk below. If they fall into a swamp below, at what height do you start hurting car occupants? If they can’t drive over the curb maybe that is adequate, maybe a bumper height guard rail or cable system of some sort. Maybe tied back just below the pavement with an auger type tie back at each post and angled down into the ground below the parking.

 

[chicopee]

Are you referring to Jersey barriers? I would say whether it's 1',10' or 100' difference in elevation, some form of protection would be needed for the expected traffic.

 

[RFreund]

Good points.

Chicopee - This would most likely be a guardrail. This is for a parking lot, more specifically a car dealership parking lot.

This really is not my call at the end of the day as I am just the wall designer and the civil engineer will make the final decision. In any case, this came up as we showed guards for all wall heights but the owner does not want the guardrail to block the view of the cars which I suppose is understandable, but there will need to be guardrails at some point. The cable suggestion by DH might solve this, for this instance (Thanks DH!). I'm just trying to see if there is a code reference or standard of practice. To me I think 1' or 2' is a bit low to require a guardrail, but maybe I'm wrong...

This is what IBC says for parking garages:

406.2.4 Vehicle barrier systems. Vehicle barrier systems not less than 2 feet 9 inches (835 mm) high shall be placed at the end of drive lanes, and at the end of parking spaces where the vertical distance to the ground or surface directly below is greater than 1 foot (305 mm). Vehicle barrier systems shall comply with the loading requirements of Section 1607.7.3.
Exception: Vehicle storage compartments in a mechanical access parking garage.

This is what IBC says for Means of Egress -> Guards:

1013.1 Where required. Guards shall be located along open-sided walking surfaces, including mezzanines, equipment platforms, stairs, ramps and landings that are located more than 30 inches (762 mm) measured vertically to the floor or grade below at any point within 36 inches (914 mm) horizontally to the edge of the open side. Guards shall be adequate in strength and attachment in accordance with Section 1607.7.
Exception: Guards are not required for the following locations:
1. On the loading side of loading docks or piers.
2. On the audience side of stages and raised platforms, including steps leading up to the stage and raised platforms.
3. On raised stage and platform floor areas, such as runways, ramps and side stages used for entertainment or presentations.
4. At vertical openings in the performance area of stages and platforms.
5. At elevated walking surfaces appurtenant to stages and platforms for access to and utilization of special lighting or equipment.
6. Along vehicle service pits not accessible to the public.
7. In assembly seating where guards in accordance with Section 1028.14 are permitted and provided.

EIT

http://www.HowToEngineer.com

 

[ACtrafficengr]

"...the owner does not want the guardrail to block the view of the cars..."

... but he doesn't mind customers and employees falling on their heads?

I think you can make a case that if handrail is needed, it should be stout enough to keep car occupants safe, too. Or could you place the curb so the distance between it and the handrail is greater than the rear overhang of the vehicles?

 

[Debaser]

In the first instance I think you need to be very careful with these terms, as you have found they are not interchangeable (although that doesn't stop people trying).

My understanding is that a barrier (or a vehicle restraint systems) is just that, a system that can - in certain circumstances and load cases - provide a restraint to vehicles. On the other hand, guardrail is there simply to prevent peds falling from a height, or down a slope, and is therefore completely different in what loads it is designed to take.