What Is A Balloon Framing in Construction?
What Is A Balloon Framing in Construction?
Balloon framing is a method of timber construction that was popular in the United States and Canada from the late-19th century to the mid-20th century. It is a less time-consuming and less material-intensive method of building a house, and it is the predecessor to modern platform framing or advance framing techniques.
Balloon framing uses 2×4 studs spaced every 16-24 inches, but unlike platform framing, where the studs only extend one story, balloon frame studs are commonly 16-24 feet long and extend from the basement to the roof without interruption.
This allows for the use of smaller members that can be attached using cut nails rather than the complex mortise and tenon joinery required in timber framing, making it easier for more builders to have the skills to construct balloon frame houses.
The availability of easily milled and shipped lumber via the expanding railway also contributed to a building boom as the cost and time of construction decreased significantly.
History Of Balloon Framing
Balloon framing was a construction method used for building houses in the United States and Canada from the late 1800s to the mid 1900s. It was often used in the Queen Anne and Shingle style architectures of the time.
This method involves using long timbers to create a frame that extends from the foundation to the roof. However, it has since been replaced by platform framing, which involves building each floor with floor-to-ceiling timber panels and a floor deck that serves as the base for the next floor.
One major drawback of balloon framing is that it allows fire to spread easily because there are no breaks in the frame. Platform framing, on the other hand, includes a fire break between each floor.
To improve the fire safety of existing balloon frame houses, it is possible to add fire-stopping elements to the walls, although this can be a difficult and time-consuming process as it requires removing interior walls or exterior siding to access the stud top plates.
Advantages And Disadvantages Of Balloon Framing
Balloon framing is a popular construction technique in Canada and the United States because it does not require a skilled and experienced carpentry workforce.
It has several benefits, including;
- The use of simple sockets rather than complex joints.
- The ability to be quickly constructed by those with basic building skills and equipment.
- The use of affordable and renewable wood resources.
- The reduction in the need for heavy machinery.
- Lower potential for shrinking, improved load-bearing capacity.
- Improved wind load resistance, the possibility of large and decorative windows,
- The ability to build tall chimneys, and the ability to create open two-story entryways and large rooms.
Disadvantages OF Balloon Framing
The balloon frame system has several disadvantages. It uses long wood studs which take longer to install than the shorter ones used in platform framing and creates continuous spaces between them which can act as chimneys in case of fire.
It also has significant shrinkage due to the orientation of the grain in the wood. The use of large, difficult-to-handle lumber and the presence of vertical hollow spaces that can allow the fire to spread quickly are additional drawbacks.
Exposure to wooden studs can also present various risks. Building a balloon frame structure is more expensive due to the need for specialized lifting equipment and skilled labor, as well as the higher labor costs due to the use of scaffolding for workers at the increased height of the gable walls.
In addition, the use of longer studs increases the price per linear foot. The process of raising the walls can also be dangerous and requires specialized equipment and trained labor. OSHA has identified the risks associated with lifting balloon-framed walls.
Construction Process Of Balloon Framing
Balloon framing is a technique of building construction that was commonly used during the 1800s in North America. It involves constructing a wooden skeleton of walls and floors for the building, with each floor being supported by the wood frame below it.
The process begins with setting up the concrete foundation and then erecting the walls from bottom to top using dimensional lumber such as 2x4s or 2x6s.
Following this, a row of nails is driven into the studs to form “balloons” which will help support joists and provide additional structural support for the house.
Once all of these steps are completed, roof trusses are installed on top and plywood or other sheathing materials are fastened over them to complete the construction.
Balloon framing is not often used today due to its relative expense compared to other methods, but it remains an important part of architectural history nonetheless.
