Humans perspire to remove excessive heat from their system. Without this natural defense mechanism, a heat stroke can occur and, if not attended to, can be fatal. Buildings, especially barns, also require significant measures to vent or draw off harmful heat from their contents. If left unchecked, the results could be catastrophic for the building structure and its inhabitants as well.

Next to lightning, spontaneous combustion is perhaps a barn's worst enemy. This unusual phenomenon often occurs in piles of green hay or leaves when the trapped heat cannot escape quickly enough "¦ resulting in fire.

Ventilating barns to reduce the incidence of spontaneous combustion evolved into a unique blend of art and science by providing function without sacrificing aesthetics. All styles of barns, whether bank, tobacco, round, crib or Dutch, constructed in wood or masonry, address the need for cross-ventilation.

The famous Pennsylvania bank barn, with its signature cantilevered fore bay, earned its name and reputation by providing two different grade levels of access: one to an upper floor, via an embankment, and the other to the ground floor. The upper level served as storage for wagons, equipment, hay and straw. Fodder was conveniently dropped to the livestock below through trap doors.

Ventilating the upper level assured that heat accumulation from the products of the freshly harvested fields would be drawn away.

The earliest examples of bank barns are constructed of massive masonry gable walls of native field stone or locally manufactured brick. These gable walls were designed to provide very clever ventilation devices through the use of tall, thin, narrow slots arranged symmetrically in the stonework, or through intricate geometric patterns woven into the brick and resembling a quilt or counted cross-stitch.

Although the 3-inch-wide stone slots present an outward appearance of insignificance, the interior dimension is splayed five to six times wider to maximize air flow and introduce daylight.

Barns typically reflected the culture, values and style of the families who built and owned them. A source of great pride and tradition, the architectural character and details reflected in a barn's design were often consistent with the style of the farmhouse and supporting structures.

Whether neo-traditional, Gothic Revival, Italianate or Queen Anne, signature details such as pointed arches, square tops, fans or circles were expressed in the design of the ventilation louvers. Plain or fancy, painted or unpainted, the louvers provided purpose and character to the imposing farm structures.

Cupolas, a more sophisticated ventilation solution, originated in the Connecticut Valley region. There, farmers discovered this unique design would draw warm, moist air upward and outward using a chimney or smokestack effect. The cupola's prominent location afforded owners another opportunity to personalize the design to their individual taste and style. Weathervanes would often add the final touch of form and function to the cupola.

Today, barns often rely on mechanical means to assist in ventilating the interior spaces. Although the end result may be the same, the aesthetic rewards are, unfortunately, missing.

So the next time you take a drive in the country, take note of the unique ventilation details that some farmers may say is the main eVent when it comes to protecting their investment!

This column is contributed by Gregory J. Scott, a local architect with 32 years of national experience in innovation and design. blog comments powered by Disqus