A successful fireground operation begins with a proper size-up that identifies the type of construction involved. Balloon-frame style construction is one of the two most common styles of traditional wood-frame construction, with platform frame construction being the next most common.
Balloon-frame, which was built from the early 19th century until World War II, poses unique firefighting problems because it lacks horizontal fire stops between the studs inside of the exterior walls.
Most balloon-frame homes are two or three stories tall. This allows for unimpeded fire spread from the basement to the attic in a matter of minutes via the interior stud channels of the exterior walls.
Platform frame became popular after World War II and shortened the exterior walls to 8 or 10 feet and provided fire stopping between floors.
Fire’s pathway
The lack of fire stopping within the exterior walls can pose a major challenge for firefighters. In addition, the joist channels underneath the floors are interconnected with the exterior wall stud channels. A basement or interior fire that enters this void space can result in vertical and lateral fire spread throughout the structure.
If conditions permit, check the attic void soon after arrival. Once fire gains control of the wall and floor voids, it often dooms the structure. It is common to find a large finished room within the attic of these homes. This further complicates accessing a fire that has extended into the attic void.
I responded to a fire in a balloon-frame residence one evening in which the fire originated in the basement. Several minutes after crews gained entry into the basement, fire began to vent from the attic windows.
We discovered the attic room had a finished hardwood skating rink installed over the floor, covering the entire top floor of the residence.
Another common avenue of fire spread within a balloon-frame structure is the transoms. The transom is an operable window above interior room doors to allow air circulation while the door is closed. Fire can quickly breach the transom and spread unimpeded from the room of origin into hallways and adjoining rooms.
Additionally, balloon-frame homes often have open stairwells that are quickly compromised by the heat, smoke and fire. This may necessitate laddering for the rescue of occupants. They also have large search areas.
Wolf in sheep’s clothing
Until recently, it was reasonable to assume most two-story or greater wood-frame homes built before World War II were balloon-frame. However, modern lightweight wood-frame construction methods can achieve the look of older Victorian-style construction.
Do not be deceived. Fire spread characteristics and collapse potential are vastly different in lightweight wood frame structures compared to homes of the balloon-frame era.
Often, the true balloon-frame constructed homes will be located in older neighborhoods built in that era, and may exceed 5,000 square feet. Whereas, the new lightweight-constructed homes will likely be in newly developed locations. Their average size is between 2,500 and 3,000 square feet.
A closer look at a newly built home will reveal building materials not available in the early 20th century, such as vinyl siding, vinyl window, synthetic porch decking and decorative trim.
Safety precautions
Traditional balloon frame homes were often built and can be identified with native stone or block used in the foundations. Original lot sizes found in many traditional homes tend to be narrow and deep, compared to lots built upon in recent years, which tend to be wider and less deep.
Additionally, these units are also being converted from a single-family dwelling into multiple apartments, frat houses, and bed-and-breakfast type occupancies are common. Multiple occupants should be expected in these conversions often with the only means of egress being a single, narrow interior stairwell.
Fires in balloon-frame homes can rapidly spread throughout the structure in a variety of ways, entrapping unsuspecting occupants. Such was the case of an early morning house fire in Stamford, Conn. on Christmas Day 2011, which claimed the lives of five family members.
Firefighters must be prepared for a variety of challenges, with limited staffing, when arriving on scene of a balloon-frame structure fire. These fires will be labor intensive and will pose a significant challenge for firefighters. Training and pre-incident planning are essential for successful operations.
In addition, public education training is essential for the occupants regarding the importance of smoke alarms and escape planning. The use of residential escape ladders from upper story bedrooms is a good recommendation to discuss with homeowners.
