Building a pole barn is a complex construction project. It’s relatively easy to get caught up in the nitty-gritty details of designing your post frame building.
For instance, what size should you make your farm shop? Which color combination best matches your pre-existing pole barns? Should you include wainscoting? How about a front porch? The number of doors and windows?
Don’t get us wrong; those details require some thought. But you don’t want to overlook or undervalue building features that promote structural integrity, such as pole barn ventilation and condensation.
This article discusses four ways you can ventilate your post frame building to prevent moisture buildup and mold growth.
What is Pole Barn Ventilation?
Ventilation is the intentional exchange of indoor air without outdoor air. The primary purpose of pole barn ventilation is to prevent condensation (i.e., moisture buildup).
Condensation occurs when warm, moisture-laden air contacts a cool surface, such as the underside of your metal roof. Since cooler air cannot hold as much moisture as warmer air, the excess humidity turns into water droplets.
Moisture can cause the following damage to any structure, whether it be post frame or stick-built:
- Mold growth
- Lumber decay
- Poor human and animal health
- Discoloring of stored possessions (e.g., vehicles and furniture)
Consequently, vented building features work to minimize the temperature difference between indoor and outdoor environments by drawing in the fresh air and exhausting stale particles.
4 Ways to Ventilate Your Post Frame Building & Promote Air Circulation
As mentioned above, pole barn ventilation goes a long way towards controlling condensation. The old saying in post frame construction goes, “Your IN is only as good as your OUT.” To put it another way, your airflow is only as good as its ability to escape your pole barn.
Let’s take a look at your ventilation options, shall we?
1) Overhangs
We learned this fact in grade school science, but air rises as it warms. The heat causes gas particles to expand, decreasing the density. Warm (less dense) air floats on top of cold (more dense air). This force causes warm air to rise.
Having 1’ or 2’ overhangs with vented soffits on the sides of your post frame building will draw cool air inside. Then ridge vents at the peak of your metal roof will release the humid air.
Editor’s Note: Overhangs on the ends of your pole barn are purely for aesthetic reasons. A solid soffit prevents air from entering your post frame building.
If your building design doesn’t include overhangs, you can always install an eave vent to regulate airflow.
A vent is mounted underneath the pole barn eave and lets air enter your roof space. Again, the air will exit the post frame building via the ridge vent. Although eave vents are cheaper than overhangs, they’re less effective and attractive.
Overall, vented overhangs, ridge vents, and eave vents enable the pole barn to breathe and stay drier.
2) Cupolas
Often added for aesthetic purposes, cupolas can aid with ventilation. These ornamental domes can be functional or nonfunctional. If you opt for the former, you’ll need to have electricity installed for the fans.
Adding a cupola to your pole barn will allow trapped heat to escape through the fan and side vents.
They're a great ventilation feature if you’re interested in building a horse barn or riding arena. Moisture from the manure will rise and exit the structure; thus, improving the indoor air quality for you and your horses. Say goodbye to musty air!
Cupolas are available in a variety of styles and sizes. Standard dimensions include 24'', 36'', or 48'' bases, but they can be as big as 66''. For a personalized touch, you can top it off with a weathervane.
As with any building feature, proper installation is critical. The assembly of a cupola is fairly simple, but failure to follow instructions can result in collapse or water leakage.
For design inspiration, we recommend flipping through MWI Component's "Cupola Look Book." Founded in 1985, MWI Components is the leading manufacturer and supplier of products for post frame buildings.
3) Doors & Windows
It seems evident, but doors (e.g., overhead, sliding, or walk-in) and windows are standard building features that encourage air movement.
During the spring and summer months, do you open the windows or screen doors to let a breeze into your house? If we had to guess, the open doors and windows are located on the east and west side of your home.
Why do we make that speculation? Typically, the wind blows in a west-to-east direction.
Ultimately, the placement of this ventilation system depends on the building’s purpose and location. The way the wind blows will determine which doors and windows you’ll want to open for the best ventilation.
Moreover, we recommend even distribution of doors and windows for the best results.
Do you need help envisioning the right spot? Design your post frame building using our 3D Design Tool. Save, print, or email the floor plan to family and friends.
4) Mechanical Ventilation
The building features listed above are great examples of natural (also known as passive) ventilation. In some cases, natural ventilation may not be enough. For example:
- Curing Concrete: Whether you’re pouring a concrete floor at the time of new construction or a later date, your solid surface will need time to cure.
This process ensures the cementing property stays hydrated, so the slab continues to harden and strengthen. Concrete surfaces are cured using a mist machine or putting down moisture-retaining fabrics (e.g. burlap and cotton mats).
The longer the concrete is moistened, the more durable and stronger it’ll be. But you’ll want to make sure the moisture buildup doesn’t ruin other aspects of your pole barn. - Storage or Use of Chemicals: Are you a farmer who stores fertilizers and chemicals? How about an autobody repair shop or classic car restoration enthusiast that uses spray paint? These gases may require increased ventilation.
- Livestock: As mentioned above, large animals generate ample amounts of moisture. Combine this factor with their odor, and you’ll notice a greater need for vented building features.
- Pole Barn with Living Quarters: Some building codes require a certain amount of air exchange and energy efficiency for residential buildings. You may have no choice but to incorporate other ventilation methods. The same can be said about commercial post frame buildings that are human-occupied.
Enter mechanical ventilation. It controls air movement by using one or more ceiling fans.
Editor’s Note: Mechanical ventilation isn’t commonly used in post frame construction because it increases initial, operating, and maintenance costs.
Do you need help looking for a reliable fan manufacturer? Here are our top ceiling fan brands for your pole barn:
- Big Ass Fans: Yes, you read their brand name right. Their high-volume, low-speed (HVLS) airflow approach is key to making your pole barn more comfortable and energy-efficient. By installing their ceiling fans, you can save up to 30% in energy costs and feel a 10ºF temperature difference.
- Humongous Fan: This company also offers HVLS fans with performance-engineered blades. There are numerous “application types, product variants accessories, and customization options.” Similar to Big Ass Fans, their ceiling fans offer year-round energy savings.
- Hunter: Their ceiling fans are available in different sizes, styles, features, materials, and colors. Regardless of the building type, Hunter has the perfect fan for you.
- Environfan: Their “powerful, all-metal, heavy-duty” fans are engineered to excel in any application. You can expect energy savings of up to 30% and 50% during the winter and summer months, respectively.
However, passive ventilation is favored by customers from a cost-effective perspective.
How Will You Ventilate Your Post Frame Building?
If you’re going to build a pole barn, you need to invest in proper ventilation. Multiple building features will protect your structure from moisture damage.
To avoid condensation issues, we recommend downloading our “Condensation Control Guide.” This FREE resource lists the five ways to proactively manage moisture buildup in your post frame building, one of which being – you guessed it – ventilation.
If you're ready to move forward with your post frame project, we also recommend you check out The Ultimate Guide to Building a Pole Barn. This guide will help you navigate the steps that you need to take to insure your project gets done on time and under budget.
Have more questions about pole barn ventilation not covered in this article? Please contact FBi Buildings at 800.552.2981 or click here to email us. If you’re ready for a price, click here to request a quote, and a member of our sales team will call you.