Straw Bale Greenhouse: 10-Step Project for Cheap Insulation

Last Updated on March 8, 2024 by teamobn

A straw bale greenhouse is a type of greenhouse that uses straw bales as walls.

There are countless reasons why having a greenhouse is an excellent idea. But they do require a sizeable investment. The cost of buying materials for a greenhouse alone can cause some to pause and reconsider.

A greenhouse made from straw bales? It’s certainly interesting but many would be doubtful about this idea. This type of greenhouse is often used in cold climates as the straw bales help to insulate the space.

Straw bale greenhouses are typically built with a frame of wood or metal, and the straw bales are then stacked on top of the frame. The straw bales can be left natural or they can be covered with a layer of plaster or stucco.

Yes, it’s affordable (even money-saving for some), environmentally friendly and provides good insulation. But is it strong enough?

A straw bale greenhouse has the potential to be an excellent addition to your home, provided you take the necessary precautions during construction. As with any construction project, there is always the potential for disaster, but if you build your straw bale greenhouse carefully and take into account the intense weather conditions that may occur in your area, you should be fine.

But there are large straw bale greenhouse constructions that prove this build is one great option you can consider. With enough research, proper design, and quality build, a straw bale greenhouse should work just as well as the more common greenhouses that people DIY.

The example that you see above is a nice start, BUT it’s an unfinished project.

Building a Straw Bale Greenhouse

Materials

• PVC
• Timber
• Clear Corrugated Roofing Panels
• Straw Bale

Tools

• Cordless Drill
• Measuring Tape
• Spirit Level
• Shovel
• Hammer
• Table Saw

Instruction

1. Plan Your Greenhouse

• Determine the size and location of your greenhouse. Ensure it receives adequate sunlight and is protected from strong winds.
• Sketch your design, including dimensions and the placement of the door and windows.

2. Prepare the Foundation

• Clear the area and level the ground using a shovel and spirit level.
• You can create a simple foundation by burying PVC pipes or timber in the ground to support the structure. Ensure they are level and securely in place.

3. Construct the Frame

• Use timber to build a rectangular frame that will serve as the skeleton of the greenhouse. Cut timber to the required lengths with a table saw.
• Assemble the frame using a cordless drill and screws. Ensure the frame is square and level.

4. Install the PVC Arches

• Cut PVC pipes to create arches that will span the width of the greenhouse. These will support the roofing panels.
• Secure the PVC arches to the timber frame at regular intervals to ensure stability and support for the roofing panels.

5. Position the Straw Bales

• Place straw bales around the perimeter of the frame, stacking them to the desired height. These bales will form the walls of the greenhouse.
• Ensure the bales are compact and positioned tightly against each other to improve insulation.

6. Apply Plaster to Straw Bales

• To protect the straw bales from the elements, apply a layer of plaster or a similar protective coating. This step is crucial for the longevity of the walls.

7. Install Roofing Panels

• Lay the clear corrugated roofing panels on top of the PVC arches. Cut the panels to size if necessary using a table saw.
• Secure the panels to the PVC pipes using screws and a cordless drill, ensuring there are no gaps for heat to escape.

8. Install Doors and Windows

• Construct a door frame and window frames from timber. Install them in the designated openings.
• You can use additional PVC or timber to create the door and window sashes. For windows, consider a design that allows for easy opening for ventilation.

9. Final Touches

• Check the entire structure for any gaps in the walls or roof. Seal any found to enhance insulation.
• Install a thermometer and humidity gauge inside to monitor conditions.

10. Plant and Enjoy

• Prepare the inside of your greenhouse for planting. You may need to bring in soil, planters, or create raised beds, depending on your design.
• Plant your seeds or seedlings and enjoy the benefits of an extended growing season.

Factors to Make Your Straw Bale Greenhouse Efficient

Plastering the straw bales

Make sure to protect the straw bales from the weather by plastering them. Plastering the bales will help extend their lifespan and prevent rotting. Make sure to do this as soon as possible after putting the bales in place, as exposure to the elements can cause them to degrade quickly.

Leaving them exposed will cause them to eventually rot, which you obviously do not want. There are many sources for a plaster recipe out there. You can also find one that includes cement to make your straw bale walls more water-resistant.

Include a window

When designing your greenhouse, be sure to include operable windows. These windows will allow you to release excess moisture that builds up inside, helping to protect the straw bale walls from deterioration. By venting the greenhouse regularly, you can prolong the life of your straw bale walls and ensure a healthy growing environment for your plants.

Use Polycarbonate Sheets

Last but not the least, use polycarbonate greenhouse sheets if possible – for your ceiling and non-straw bale walls. Polycarbonate sheets are a strong, double-wall, lightweight material that provides great light transmission but filters out harmful rays at the same time. It’s a perfect complement to your relatively light straw bale walls as well as great for your plants!

Now as mentioned earlier, building a good straw bale greenhouse will depend on many factors – space, location, budget, available materials, weather conditions, and more. If you carefully consider all of these factors before starting your project, you’ll be much more likely to end up with a greenhouse that meets your needs and lasts for years to come.

If you lack experience in building construction, be sure to solicit the help of professionals or friends who have more knowledge in design and construction when planning to build a straw bale greenhouse. This will help ensure that your greenhouse is built properly.

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Benefits of Straw Bale Construction for Greenhouses

Straw bale construction offers a unique and sustainable approach to building greenhouses. This method, which utilizes straw bales as primary building materials, has gained popularity for its environmental benefits, energy efficiency, and affordability. 

Let’s explore the advantages of choosing straw bale construction for greenhouses.

Sustainable and Environmentally Friendly

Straw bale greenhouses are at the forefront of eco-friendly construction, significantly minimizing the environmental footprint of building projects. The straw used as the primary material in these greenhouses is a byproduct of grain production. 

Typically, this straw might be considered waste, often burned or disposed of in ways that contribute to pollution and waste management issues. By repurposing straw bales for construction, straw bale greenhouses transform this agricultural byproduct into a valuable resource, thus promoting waste reduction and sustainability.

This construction method not only recycles a plentiful agricultural byproduct but also leverages it to create energy-efficient structures. Additionally, as straw bales naturally decompose, they sequester carbon dioxide, which contributes to reducing greenhouse gas emissions. 

This carbon capture feature is a crucial aspect of straw bale greenhouse construction, aligning with the goals of eco-conscious gardeners and farmers who aim to minimize their carbon footprint. Embracing straw bale greenhouses reflects a commitment to environmental stewardship, showcasing a sustainable approach to agriculture and building that supports the planet’s health.

Superior Insulation Properties

The remarkable insulation properties of straw bale construction are a key driver behind the decision to build a straw bale greenhouse. Straw bales boast high R-values, a measure of thermal resistance, making them exceptionally good at insulating spaces. 

This natural insulation efficiently traps heat during cold weather, ensuring the greenhouse remains warm and conducive to plant growth without excessive energy use. Similarly, during hotter periods, straw bales help keep the greenhouse cooler’s interior by blocking out unwanted heat.

This ability to maintain a stable temperature is fundamental for gardeners and farmers who aim to extend their growing seasons. In regions with harsh winters or very hot summers, the insulation provided by straw bales can make the difference between a flourishing greenhouse and one that struggles to support plant life. 

For some climates, the insulation might even enable year-round gardening, a significant advantage for producing fresh produce outside of the traditional growing season. The stable internal environment fostered by straw bale insulation benefits plant growth and contributes to energy savings by reducing the need for heating and cooling systems within the greenhouse.

Incorporating straw bales into greenhouse construction offers a blend of environmental sustainability and practical benefits. Using straw bales minimizes waste and promotes the use of renewable resources while providing superior insulation that can enhance the efficiency and productivity of greenhouses. These qualities make straw bale greenhouses attractive for those seeking to combine their gardening endeavors with a strong commitment to ecological responsibility.

Cost-Effective

Constructing a straw bale greenhouse presents a cost-effective alternative to traditional greenhouse building methods. The affordability of straw bales, particularly when sourced locally, significantly reduces the initial material costs involved in the construction process. This accessibility of materials is a key factor that lowers the financial barriers to building a greenhouse, making sustainable gardening more achievable for a wider audience.

Furthermore, the superior insulation properties of straw bales play a crucial role in minimizing the ongoing operational costs associated with running a greenhouse. By effectively maintaining a stable internal temperature, straw bale greenhouses reduce the need for additional heating in colder months and cooling in warmer months. 

This natural regulation of temperature leads to substantial savings on energy bills over time, enhancing the overall cost-effectiveness of the investment. Gardeners and farmers who opt for a straw bale greenhouse thus benefit from reduced upfront construction costs and ongoing operational savings, making it an economically wise choice for maximizing greenhouse investments.

Energy Efficiency

Straw bale greenhouses are lauded for their unparalleled energy efficiency, a direct result of the exceptional insulation properties of straw bales. This natural insulation ensures that less energy is required to maintain optimal growing conditions within the greenhouse, regardless of external weather conditions. 

By keeping the interior warmer during cold periods and cooler during heatwaves without the need for extensive mechanical heating or cooling systems, straw bale greenhouses significantly lower the energy consumption typically associated with maintaining a productive growing environment.

This reduction in energy usage directly contributes to a lower carbon footprint for the greenhouse, aligning with sustainable living practices and the goals of environmentally conscious individuals. Moreover, the energy efficiency of straw bale greenhouses translates into lower utility costs, making it an attractive option for those looking to reduce their environmental impact while also managing their expenses. 

The combination of reduced energy requirements and cost savings underscores the appeal of straw bale greenhouses as a sustainable and economically smart choice for gardeners and farmers committed to energy-efficient and eco-friendly gardening solutions.

Acoustic Insulation

The acoustic insulation properties of straw bale construction are a standout feature that enhances the appeal of straw bale greenhouses. While not immediately apparent, the value of this benefit becomes clear, especially in environments where external noise could detract from the serenity of the gardening experience. Urban areas, often bustling with noise from traffic and industrial activities, can undermine the tranquility essential for a relaxing and meditative gardening environment. 

A straw bale greenhouse acts as a natural sound barrier, significantly reducing noise pollution and creating a quiet, peaceful oasis for both plants and gardeners. This acoustic insulation contributes to a more pleasant and focused gardening environment, where the stress of the outside world fades away, allowing gardeners to immerse themselves fully in the nurturing of their plants.

Aesthetic Appeal

Straw bale greenhouses are functional and possess a distinctive aesthetic appeal that sets them apart from conventional greenhouses. Their natural materials and earthy tones allow them to blend seamlessly into various landscapes, from rural settings to suburban backyards. The rustic charm of straw bale construction, with its textured walls and warm hues, evokes a sense of connection to nature and traditional building methods. 

Furthermore, the flexibility of straw bale construction allows for customization with plasters or renders, offering endless possibilities for personalization. Gardeners can choose finishes that reflect their style or complement existing structures on their property, making each straw bale greenhouse a unique and visually appealing addition. This aesthetic versatility ensures that a straw bale greenhouse is not just a place for growing plants but also a beautiful and inspiring space that enhances the overall appeal of any property.

Versatility and Customization

The inherent versatility and customization potential of straw bale construction are what make straw bale greenhouses such a valuable option for gardeners and farmers alike. Whether the project is a modest backyard greenhouse or a larger-scale commercial venture, straw bales can be configured to meet a wide range of design requirements and spatial constraints. 

This adaptability allows for creative freedom in the design process, enabling the construction of greenhouses that perfectly suit the specific needs and preferences of the user. The structural flexibility of straw bales means that greenhouses can be tailored to optimize light exposure, accommodate unique plant species, or integrate into existing landscape designs. 

Moreover, the option to customize a straw bale greenhouse’s exterior and interior finishes further enhances its appeal, providing an opportunity to create a functional space that reflects individual aesthetic and environmental values. This level of versatility and customization makes straw bale greenhouses a compelling choice for those looking to create a highly personalized and effective growing environment.

Straw bale greenhouses offer a sustainable, efficient, cost-effective solution for extending the growing season. Their superior insulation properties, environmental benefits, and aesthetic appeal make them an excellent choice for gardeners and farmers seeking an alternative to traditional greenhouse construction methods. By choosing straw bale construction, you’re not just building a greenhouse but committing to sustainable living and energy efficiency.

FAQ on Constructing a Straw Bale Greenhouse

Conclusion

Building a straw bale greenhouse offers an eco-friendly, cost-effective solution for extending the growing season energy-efficiently. The natural insulation properties of straw bales ensure a stable and conducive environment for plant growth, reducing the need for artificial heating or cooling. Embracing this sustainable construction method not only supports agricultural recycling but also enhances the aesthetic appeal of any garden or farm.

For more sustainable greenhouse ideas, check out our guide on building one with old windows!