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Building Construction | Posts | Structural Integrity | Building Design

Pole Barn Height: How Tall Can My Post Frame Building Be?

May 2nd, 2017 | 11 min. read

Angie Dobson

Angie Dobson

Angie graduated from Indiana State University with a Bachelor of Science in Interior Design. Prior to joining the FBi team, Angie was a kitchen and bath sales consultant in Lafayette, IN. In 2012, she started with FBi as the Inside Sales/Marketing Assistant. Today she holds the role as Marketing Project Manager. Angie grew up in a farming community and has always enjoyed helping her family on the farm. A past 10 year 4-H Member, her passion for livestock pursued her to take a career in the agriculture field. Her and her husband live in Northwest Indiana with their two daughters. In her free time, she enjoys outdoor leisure activities and spending time with friends and family.

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Post frame construction is touted for its durability, sustainability, and cost-savings

Perhaps, the building system’s biggest advantage is design flexibility. It’s the very reason why architects, designers, and engineers favor this construction method over others.

Every day, pole barns are going up in rural and suburban areas. Take a look for yourself when running errands in town or traveling across the state. 

You’ll see agricultural, commercial, residential, and equine buildings of all shapes and sizes. It makes you wonder, “How does one determine his/her pole barn dimensions?” 

In this article, we discuss the five essential questions you should ask yourself when determining pole barn height.

As for length and width, we recommend reading our blog over popular building sizes.

5 Questions to Ask Yourself When Determining Pole Barn Height

 

1) What is the primary use of your post frame building?

Tall_Farm_ShopFirst, pole barn height is subjective. It boils down to the intended use.

For instance, hardworking farmers need a taller tractor & implement storage building to accommodate large doors and heavy machinery. It’s convenient to store and move large implements under one roof.

Warehouses need higher ceilings for easier access to assembly lines, deliveries, equipment, and trucks.

Avid outdoorsmen need ample clearance when housing their boat and camper in the off-season.

Recently, pole barn construction has become a popular housing option. Post frame homes can be one- or two-story depending on the homeowners’ needs.

Equine enthusiasts can add dimension to their horse barns, whether it be for an observation lounge or hay storage.

Don’t forget to consider future use. We always recommend adding extra square footage. Why? Because no one has ever said, “My pole barn is too big!” 

Unfortunately, some customers don’t think that far in advance. Eventually, they run out of space and have to add-on to their existing post frame structure.

Taking the time to contemplate future purchases (big or small) will help you save money in the long run. Not to mention, it’ll spare you from buyer’s remorse and growing pains.

Pole Barn Quote_FBi Buildings

 

2) How does height affect the structural integrity of your pole barn?

Tall_Pole_Barn_Structural_IntegrityStructural integrity refers to a pole barn’s ability to withstand anticipated loads without breaking.

Any post frame building, regardless of size and location, must be designed to resist vertical and lateral loads safely.

Vertical and Lateral LoadsVertical loads act in the up-and-down direction. Popular examples include:

Lateral loads act in a direction parallel to the ground (e.g., earthquakes and high winds). These forces can work in any direction. Therefore, the pole barn must be designed to withstand loads, both parallel and perpendicular to any wall.

All structural loads must be able to pass from the areas in which the load is applied. This transfer of forces through the post frame structure is called the load path. A continuous load path transfers all vertical and lateral loads from one building component to another until they reach the ground.

If the load path flows continuously without interruption, there will be no structural damage. However, one break in the course can cause significant damage. 

One “weak link” is all it takes to compromise the structural integrity of your pole barn. Therefore, each building component must be strong enough to carry out these anticipated design loads.

While the building system consists of multiple parts, we detail specific areas affected by pole barn height.

Structural Integrity eBook_FBi Buildings

Columns

Parallam_PSL_ColumnColumns also referred to as posts, are integral parts of a post frame building. They support the entire roof system and transfer all vertical loads to the footings. In addition, posts are the backbone of your walls and assist in resisting horizontal loads.

The term “laminated column” refers to two or more layers of dimensional lumber that has been mechanically laminated with nails. These posts are made from 2x6 or 2x8 lumber.

In taller buildings, you can upgrade the columns to 2x12 lumber. Or, you can use engineered wood, such as Parallam® PSL Columns.

This manufacturing process uses veneer strands, which allow for higher load capacity. Because it’s made with conjoined veneers, Parallam is available in specialty lengths that exceed conventional lumber.

If engineered wood is incompatible with your building design, you can opt for a hybrid system. This approach consists of steel columns and wood trusses. It’s used in pole barns where engineered lumber isn’t a viable option.

Please note that “over-sized” columns won’t necessarily make your post frame building stronger. Why? Because the diaphragm carries the majority of wind loads.

 

Diaphragm Design

In post frame construction, buildings can resist extreme lateral loads through the diaphragm design.

A diaphragm is a flat structural unit acting like a deep, narrow beam. It is usually applied to pole barn floors and roofs.

Moreover, a shear wall is a vertical diagram. It provides support for the floor and roof diaphragms transmitting forces into the foundation.

A structural diaphragm results when a series of diaphragms are properly tied together to form a unit. 

Most sheathed elements (when using good construction methods) add considerable strength to the structure.

Without the diaphragm or protective steel, columns will bear a full load of your pole barn. Open-sided buildings are a prime example.

As building height increases, so does the need for a structural diaphragm.

 

Wind Load

Residential Plan Book_Landing Page Header_PetersThe term “wind load” refers to the internal and external wind pressure placed on a structure, which is measured in pounds per square foot (psf). Engineers use wind loads to determine which building materials will withstand Mother Nature’s curveballs.

The design load is based on wind speed and building codes obtained from the American Society of Civil Engineers Standard (ASCE 7-10). This publication helps engineers determine load requirements essential to their practice.

Wind speed increases with height above ground. Consequently, taller pole barns are exposed to greater pressures. 

Furthermore, engineers account for the following influential factors when calculating your post frame building’s wind load:

  • Basic wind speed
  • Exposure
  • Topography
  • Building shape
  • Gaps and leaks

Regardless of pole barn height, wind load is a critical aspect of the building design.

Pole Barn Gallery_Pole Barn Pictures_FBi Buildings

3) How do certain building features affect pole barn height?

Pole_Barn_Front_PorchAs you mull over possible building heights, don’t forget to factor in your desired features.

For instance, you’d like to have an 18’ overhead door for quick and easy access to your farm shop. Typically,  2’ is added for sufficient building clearance.

If you prefer a wider opening or full building clearance, then a sliding door will work best for your operation. This dooring option will allow you to have an approximate 18’ opening with an 18’ eave.

Another building feature that influences pole barn height is porches, which are used to shelter people from the elements as they access the structure via a walk door

Porches are also a comfortable place to sit and enjoy the outdoors. On a lazy evening, you can sit in a wooden rocking chair with a cold glass of sweet tea and watch your children (or grandchildren) ride ATVs around the yard.

For a “cozy” aesthetic, your porch shouldn’t be too tall. 7’ to 8’ of building clearance is ideal. You may have to adjust your pole barn height accordingly. 

Are you interested in adding a lean-to? Please note that the door size on the end-wall or side-wall will affect the height of the lean-to and post frame building.

 

4) How does the site impact the building design?

In some situations, the building location may impact your building design. 

For instance, you’re outgrowing your current space and looking at potential sites to expand your commercial business

Some properties have restrictions (e.g., setbacks, easements, parking lots, and retention ponds) that limit the building size

As a result, you want to increase the height via stories for more usable square footage. 

Although it may be a feasible option, we recommend opting for a larger one-story building (if possible). Often, it’s more economical to build a larger one-story than a smaller two-story project.

Site Prep, FBi Buildings

 

5) How do building codes influence pole barn height?

Horse_Barn_ColorLastly, construction codes can dictate how tall your pole barn can be. 

Post frame structures should be code compliant, especially commercial buildings.

For local construction codes, please contact your local building official or authority having jurisdiction (AHJ).

Construction type is one of the primary indicators of allowable height (or the number of stories) by the International Building Code.

All buildings are assigned a construction type, which determines the building components’ level of fire resistance.

At FBi Buildings, our standard building is a Type 5B. This classification means our pole barns are constructed with any materials permitted by the code.

Unsurprisingly, the other factor is building use. The code uses occupancy groups to determine the allowable height. There are ten categories: A, B, E, F, H, I, M, R, S, and U. For example, a horse barn would fall under the Group U occupancy. 

Using these two variables, you can determine the allowable height by following the corresponding code tables.

Customarily, Type 5B construction is limited to one story. However, the code does provide some considerations that allow us to gain an extra story.

In these situations, we recommend working with a post frame builder and their in-house engineers. They work closely with salespeople and outside parties to meet design requirements and customers’ needs/wants.

 

How Tall Will Your Pole Barn Be?

While we can’t tell you how tall to make your post frame building, we can provide solid talking points to discuss with your professional builder and their team.

Do you already have a certain height in mind? Visualize your future post frame building with our 3D design tool. Save, print, or email your final plan to family and friends.

If not, you can browse through our pole barn gallery and FREE floor plans for inspiration.

Are you ready for a quote? Share your design with us, and a member of our sales team will give you a call to begin the estimating process.

Design Your Pole Barn_FBi Buildings


Have more questions about pole barn height not covered in this article? Please contact FBi Buildings at 1.800.552.2981 or click here to email us. If you’re ready to get a price, click here to request a quote and a member of our sales team will call you.