Agricultural Buildings Exempt from Code Requirements 2

[mfstructural]

Hey everyone,
I'm looking for the section of IBC or ASCE that talks about agricultural buildings and their design requirements. I'm a little confused. Are agricultural buildings exempt from code requirements. My understanding is that it is recommended that they be designed to local code requirements (think snow for roof loading) but it is the designer's decision. For my case I'm specifically talking about metal grain bins, but this would really apply to all non occupied farm/agricultural structures.

 

[Ceinostuv]

My understanding is that Ag buildings are not explicitly exempt from code requirements; they are exempt to many requirements, not all. The buildings can be classified as a Risk Category 1 structure and are exempted from many of the IBC and ASCE requirements. Table 1604.5 lists Ag facilities as Risk Category 1.

Edit: Man, I need to retake a writing course... my formatting is terrible.

Judgement-In-Training

 

[WARose]

By the IBC & ASCE, I think they are still under the same codes as everything else.....but obviously with relaxed standards. (For example, seismic loads need not be considered IIRC.)

Of course, that can be superseded by state and local laws. In North Carolina (for example), they passed a law to exempt "primitive structures" because a character (on one of my fav shows: Mountain Men) allowed public access to his older buildings.

 

[JStephen]

In some areas, you only have building codes in city limits, so a lot of the agricultural facilities are not covered (legally) by any building code.

 

[Rabbit12]

JStephan wouldn't the state adopted building code govern in the case of no city or county adopted code?

 

[dauwerda]

As other have alluded to above, it is not a specific exemption from the IBC. The building code itself is not a requirement unless the local jurisdiction adopts it into their laws. Depending on your location, this could be at a state, county, or city level (or all of the above). Some jurisdictions make amendments to the code when they adopt it, this could include adding or deleting information or making certain structures exempt from the requirements.

To answer your question directly; No, ag buildings are not automatically exempt from code requirements.
The local jurisdiction will specify the requirements, if they adopt the the IBC in its entirety and don't specify any exemptions then you must follow the minimum code requirements that are in the IBC (for Risk Category I structures). If they do have an exemption for agricultural buildings (or there is no code adopted for the local jurisdiction) then I suppose you don't (by law) need to follow the code requirements (Maybe ethically though?). But, if you are engineering the building/structure I don't understand why you wouldn't want to follow code requirements, that way, if there is a failure you at least still have a leg to stand on when the lawsuits start flying.

 

[dhengr]

Mfstructural:
Ag. bldgs. are kinda grandfathered in, in terms of code compliance in many locations, the farmers built them themselves, on their own property, and stored hay, farm machinery or animals in them. The general public did not much frequent these bldgs., so the farmer was left to his own devices on his own property, and sometimes suffered the consequences. This is not unlike one and two family homes which can be built to the IRC, a prescriptive code, rather than the IBC, since everyone should be entitled to shelter his own family, and play builder. Everyone is entitled to be his own engineer and contractor, at his own peril. This doesn’t mean that wind loads, snow loads, LL, etc. don’t exist, or that good engineering judgement shouldn’t be applied in the design, detailing and construction of these bldgs. So, as a registered engineer, who cares about his license, you should pretty well comply with current codes and professional stds. when you are involved in this kind of work. Of course, you will always then have to counter the comments like “my Grandpa spaced em at 36” instead of 24” o/c and it didn’t fail for 30 years.” That was the year they finaally got a snow fall approaching the design snow loads. So, you have to do some explaining and convincing when you compete with the farmer’s own bldg. or many of the Ag. bldg. builders.

 

[pmtrevisan1]

DH is spot on.
I have heard the famous "weve built like that for 30 years and never had an issue"
I simply respond with of 2 ways ( depending how I'm feeling )
1. ... then show me what the code requires.
w
2. you should be happy that someone is telling.g you how to do it right.

I find people / contractors get complacent as the havent experienced a design event. and when it does occur there will be slew of projects in my jurisdiction that will fail.

 

[Ron247]

Ag buildings may not be exempt, but they may have a lower Importance Factor depending on your code (possibly 0.8). I do not think any place allows you to do as your please. They realize you may eventually sell your place to someone else. I was told by my state that everything has to meet IBC/IRC regardless of where it is built. The difference is, that many rural areas have no inspection to confirm you built it per code. Builders claim "This is in the county so we do not have to do that" when they should be saying "This is in the County so there is no one to check to see if I built it right".

 

[dig1]

Check w/ the AHJ where the structure is to be located. NYS has exceptions for many agricultural structures

https://www.dos.ny.gov/dcea/pdf/A- 2017 Uniform Code Supplement.pdf

(page 12, 101.2.2, Exception 2). Where I live barns 30000-50000 sf are commonly erected w/o engineering plans, building permits, inspections, etc. Also, in many municipalities they are also exempt from zoning/planning requirements.

 

[dauwerda]

To add a more specific example and intent of exemptions I will use Nebraska.
Nebraska requires that all buildings/structures be designed by a licensed architect or engineering unless it falls into an exempt category. For a single family home, if it is less than 10,000 SF (including basements) a engineer is not required. If it is an IBC group U miscellaneous (includes ag buildings) anything under 5,000 SF is exempt from requiring an engineer. There are more items on the list, but you get the idea

Just because these are exempt from requiring an engineer or architect, it does not mean they aren't supposed to meet code requirements. The idea is that the smaller buildings can be built based on prescriptive codes (think IRC) and demonstrated acceptable means of construction that a building inspector can enforce.

Now, depending on the location in Nebraska, some counties or cities may have more strict requirements or some may not have a building department that enforces any code. In a location with a building department you will generally still have to conform with the prescriptive requirements or whatever the inspector may enforce (this can also be pretty hit and miss at best). In the areas without a building department you can more or less build what you please, however that is not the intent of the "exemption" as it is written in the state law.

As a practicing engineer, the exemption is in place to not require my services on all projects. It is not there to say I don't need to design to building codes for small buildings that would otherwise be exempt from my services.

Obviously every state and jurisdiction has its own laws, requirements, and exemptions. But, most of them have a similar intent.

 

[JStephen]

"wouldn't the state adopted building code govern in the case of no city or county adopted code?"
That depends on what the state adopted building code covers, or whether there is one.
In Texas, "all industrialized housing and buildings, modules, and modular components" are covered by one rule. And "the International Building Code applies to all commercial buildings in a municipality for which construction begins on or after..."
And those two items leave a lot of things uncovered.

 

[Jerehmy]

In Pennsylvania, agriculture buildings are exempt from the Uniform Construction Code. Pennsylvania has a state-wide building code, local codes only cover zoning. Farmers also really put up a stink about permitting too and claim "farmer's rights". They pretty much do whatever they want and the local code officials don't do anything.