Load-bearing Straw Bale Construction – Bring Out Your Inner Builder
Load-bearing Straw Bale Construction - Step by step video cover from How To Straw Bale Building with Andrew Morrison.
There is nothing quite like building your own space, whether it be a shed, studio, home, or commercial building. The satisfaction and joy of looking at the progress you have made at the end of each day is literally priceless!
With load-bearing construction, the step from beginner to successful builder is smaller than in framed structures, where many carpentry skills are required. That one small step may be all it takes to bring out your inner builder who loves creating!
There are two general styles of straw bale construction: Post-and-Beam Infill and Load-Bearing (Nebraska Style), with a possible third hybrid system combining the two.
Post and Beam Infill is where upright framing assemblies (posts) carry horizontal beam loads and the roof. The bales have no structural value for the building's loads, which are all carried by the structural frame. In general, the frame is either wood or steel. There are a host of post and beam variations, including a timber frame and buck and box beam structure. Learn more about straw bale wall types here.
Load-bearing construction uses bales as the structure and bears the load of the roof assembly. Under certain circumstances, it is the most cost-effective and simplest way to build.
Hybrid straw bale construction incorporates a structural system similar to post and beam infill while allowing for precompression of the bales, as with load-bearing walls. A hybrid straw bale wall utilizes principles from both primary styles.
The Reasons TO Choose Load-Bearing Straw Bale Construction
The most obvious reason to choose a load-bearing structure is the simplicity of the construction. If you have ever built with Legos, you understand how to build a load-bearing structure. The principles are the same: stack the bales properly so they cannot separate easily, and make sure to interlock the corners from one direction to another. This helps stabilize the entire structure.
Again, imagine what a Lego house would be like if you built four separate walls without interlocking them. Keep things straight and plumb. This is true in any construction and proves very important in load-bearing structures, as the bales themselves are the load-supporting structure.
With some basic common sense and construction skills, a group of people can work together and build a load-bearing straw bale house. The amount of fun that takes place is totally up to you, but in general, much is to be found on a bale-raising site!
Another common reason to build a load-bearing structure is to reduce the amount of wood or steel in a home. A load-bearing home uses the bales to support the roof assembly, so very little wood is required. Wood is still needed to add windows and doors to the building and to frame the roof and the actual box it attaches to on top of the bales; however, significant amounts of wood can be eliminated from the construction of a building with load-bearing techniques.
Simple Designs
In general, load-bearing structures have simple designs. This is in part a necessity for code requirements but it often reflects the mindset of the occupants, “Simple is better”.
With this in mind, a simple design can translate into saving money, saving time, saving headaches, and increasing fun on the job site. Simple designs can be built quickly and with friends and family instead of hired help.
Start on a Small Project First
We always suggest that people make an attempt to build a small structure before they take on a project like a home, winery, or other commercial space. Get your hands on a project, whether it is your own build, at a work party, or join us at our workshops.
Building a large structure is difficult and labor-intensive. Practicing on something small is a great idea, especially if you intend to build your own place.
Even if you plan to hire out the work, we suggest taking a hands-on challenge and building a small structure yourself to get familiar with the building process.
There are some disadvantages to load-bearing construction, mostly related to design restrictions such as building height and the number of window openings required to comply with code restrictions. However, large single-level/ranch-style residences have been built with load-bearing techniques.
If you have been feeling reluctant to actually roll up your sleeves and begin building with straw bales because of ‘performance anxiety,’ or fear of ‘doing it wrong’, we encourage you to consider getting started with a small load-bearing structure to build your skills.