Pros and Cons of Straw Bale Houses
For those who prefer using natural materials, building a straw bale house may seem like a great option. The material is eco-friendly, fairly affordable, and reasonably easy to work with, making it an appealing approach to building a home.
However, there are also pitfalls to using straw bales for construction. If you are wondering whether a straw bale house may be right for you, here are some pros and cons to consider.
Advantages of Straw Bale Houses
Straw bale houses do have some advantages. They are not overly expensive to build and tend to be energy-efficient. Plus, they are one of the eco-friendly options that are widely accessible. Here is a closer look at the advantages of straw bale homes.
Eco-friendly
Straw bale houses are incredibly eco-friendly. Straw bales are typically an agricultural by-product, one which would go to waste if not used for projects like house building.
Plus, straw is highly renewable. It can be regrown each year instead of the decades it can take to grow trees for producing lumber. Harvesting the straw also requires very little energy and the bales cost less to transport than wood, concrete, or steel thanks to their lighter weight.
Healthier
Typically, straw bales contain fewer toxins than many other conventional building materials. This can make them healthier alternatives to use in construction.
Cost-Efficient
If you want to build an efficient home, straw bales are a great choice. The high insulation factor means it costs less to heat or cool a house made of straw than certain alternatives. The material has a natural trombe effect, allowing it to store heat or coolness and release it to keep your home’s temperature comfortable.
Customizable
Straw bale walls are very accommodating. Not only can the be stacked and configured to give you an ideal room size, but the walls can be cut and shaped using a knife or chainsaw, giving you additional options.
Affordable
When you build with straw bales, the cost is comparable to a stick built home. This can make it one of the more economical alternative construction approaches.
Low Fire Hazard
Since straw bales are tightly packed, they do not burn as easily as certain other materials. The tight packing reduces airflow, something that is critical to sustain a fire.
While there is some fire risk during the construction phase (as is the case with many building materials), once the home is finished, it’s flame retardant nature decreases the risk, usually resulting in a home that better resists burning than a traditional stick built house.
Easily Sourced
Within the continental US (lower 48 states), local straw bales are almost always available locally.
Convenient
Building a straw bale house isn’t as complex as using traditional building methods. Usually, as long as one member of the construction team is highly knowledgeable, they can guide everyone else along. This is particularly convenient if you have limited access to skilled or experienced construction labor, as nearly anyone with the physical capability necessary can participate in construction.
Attractive Aesthetic
Straw bale houses have a variety of amazing aesthetic elements. The deep windows and niches are a common favorite, often providing enough depth to function as a seat or large shelf. Plus, the slightly uneven nature of straw bales gives the walls a finished yet rustic feel, which some people appreciate.
Low-Embodied Energy
It doesn’t take much energy to grow and process straw. Aside from sunlight during the growth phase, the only other energy that is required occurs during the bailing process and when the bales are transported.
Biodegradable
While a straw bale house can last for more than 100 years when constructed and maintained properly, the core material can be returned to the earth if rebuilding becomes necessary. With a bit of plowing, the straw can be added to soil and will decompose quickly without harming the environment. In comparison, fiberglass – a common traditional home insulator – can be hard to dispose of properly and isn’t biodegradable.
Disadvantages of Straw Bale Houses
While there are plenty of great reasons to consider a straw bale house, there are some risks to using this construction approach. Here is a closer look at the disadvantages of straw bale houses.
Unconventional
While some may appreciate the unconventional nature of a straw bale house, it can also create some challenges. Structural engineers may not be familiar with the building approach, making it hard to get solid plans. Inspectors in your area may also not be well educated about straw bale house construction, making it difficult to get passed during the inspection phase.
Permitting Issues
Similar to the point above, getting building permits for a straw bale house might be challenging as well. City officials may be uncomfortable with the concept, especially if you are not in an area where it is a widely accepted building method.
Pest Concerns
With straw bale homes, pests can be an issue. Insects and rodents may try to take up residence in the bales, especially when they are exposed during the building phase or are not properly finished and maintained over time.
Space Considerations
The thickness of a straw bale wall means you are sacrificing some interior space. They are typically 18 inches thick, which is substantially thicker than a stick built wall covered in sheetrock, which is usually closer to six inches thick. As a result, if a straw bale home and stick built house have the same footprint, the straw bale structure actually has less functional interior square footage.
Gaps
If not properly built, it is possible to end up with gaps between the bales. This can create thermal breakpoints, harming the energy efficiency, and could allow pests into the material or your home.
Maintenance
Straw bale houses are usually covered in plaster once the structure is constructed. Without proper maintenance, plaster can quickly degrade. This may allow water to penetrate the bales or to enter the house, increasing the odds of water damage and mold or mildew.
No Studs
When you build with straw bales, you don’t use wood to support the structure. As a result, the walls do not have studs, so hanging anything from pictures to shelves to cabinets is more complex. This means you may need to look into alternative hanging methods or use furniture pieces that rest on the floor for storage.
Skin Irritant
Working with straw can lead to irritated skin. During the building process, the material can be a bit abrasive, and some people may be allergic to the material.
Breathing Problems
Straw can also be a lung irritant. The straw dust can be bothersome, particularly if you are jostling the bails or cutting them with a chainsaw.
Usually, the best thing to do is protect your lungs, mouth, and nose by wearing a breathing filter. Wearing protective eyewear can also keep the dust out of your eyes. However, if you have an allergy, this may be insufficient.
Learning Curve
While learning to build with straw bales isn’t inherently difficult, it is different from using traditional building techniques. There is a learning curve to contend with, so the build may take longer than you expect depending on how quickly you become comfortable with the material and approach to construction.
Moisture
Straw bales need to be kept dry. Moisture can lead the bales to decay, mold, and even collapse, creating a potentially dangerous situation.
If you live in a wet climate, protecting your straw bale home from the elements is particularly daunting. While a high stem wall, long overhanging eaves, and plaster can help, these precautions can fail. And, once a straw bale is wet, it may never fully dry.
High humidity environments aren’t ideal for straw bale houses either. Since there is a higher moisture content to the air, the bales are more likely to absorb some of the water. Plus, getting the bales dried out again may be impossible in a naturally humid region.
Labor Intensive
Straw bales are usually both heavy and large. Moving them can be laborious, and stacking the bales may be outside the physical capability of some people.
Securing an able-bodied work crew can be expensive too. While labor costs are a concern for any project, you may be surprised at home much the labor aspect factors in when constructing a straw bale house.
Structural Movement
Since straw bale homes are built using a stacking technique, they can be susceptible to structural movement. This can lead to cracks in the plaster and even the collapse of a load-bearing wall, especially if the house wasn’t built well in the first place. Anything from foundation issues to high winds to seismic activity on a small scale can promote movement, as there isn’t a frame to support the house.