Discover the Art of Cordwood: A Unique Building Technique

Discover the Art of Cordwood: A Unique Building Technique

Table of Contents

1. Introduction to Cordwood Cottage
2. The Process of Building Cordwood Walls
3. Understanding Cordwood Construction
4. The Advantages of Cordwood Construction
5. Types of Wood Used in Cordwood Construction
6. The Importance of Lime-Based Mortar
7. The Benefits of Using Lime-Based Mortar
8. Preparing the Lime Mortar
9. Preparing the Log Rounds
10. Installing the Sawdust Insulation
11. Building a Cordwood Wall
12. Pros and Cons of Cordwood Construction
13. Conclusion

Introduction to Cordwood Cottage

Cordwood cottage, also known as cordwood masonry or stackwall construction, is a unique and sustainable building technique that combines logs with a variety of mortar possibilities to Create structurally sound and thermal efficient walls. In this article, we will explore the process of building cordwood walls, the advantages of cordwood construction, the types of wood used, the importance of lime-based mortar, and the steps involved in building a cordwood wall. Whether You are interested in sustainable building practices or simply curious about cordwood construction, this article will provide you with all the information you need to know.

The Process of Building Cordwood Walls

Building cordwood walls is a fascinating process that combines the strength of timber framing with the insulation and thermal mass of logs. The first step in building cordwood walls is to prepare the log rounds. These log rounds can vary in size, with smaller diameters for tighter grout joints and larger diameters for larger grout joints. Once the log rounds are prepared, a lime-based mortar is mixed using a combination of lime putty and sand. This lime mortar is then used to build the cordwood walls, with each log round placed on a bed of mortar and spaced apart with a void in between. Sawdust insulation is then added to the voids, providing additional insulation and preventing the intrusion of pests. The process of building cordwood walls requires patience and precision, but the end result is a beautiful and energy-efficient structure.

Understanding Cordwood Construction

Cordwood construction is a method of building exterior walls using logs and mortar. The logs are placed horizontally on a bead of mortar, with mortar also applied to the outside of the logs and a void filled with sawdust in the middle. This unique construction style creates walls that are both thermally massive and well-insulated. The combination of the logs and mortar provides structural integrity, while the sawdust insulation prevents heat transfer and deters pests from invading the walls. Cordwood construction offers a sustainable and energy-efficient alternative to traditional building methods.

The Advantages of Cordwood Construction

Cordwood construction offers several advantages over traditional building methods. Firstly, cordwood walls provide excellent thermal mass, which means they can absorb and store heat from the sun or a heating source and slowly release it over time, helping to maintain a comfortable indoor temperature. This can result in reduced heating and cooling costs and greater energy efficiency. Additionally, cordwood construction is a sustainable choice, as it utilizes natural and abundant materials such as logs and lime mortar. The use of sawdust insulation further enhances the insulation properties of cordwood walls, making them an attractive option for environmentally conscious builders.

Types of Wood Used in Cordwood Construction

When it comes to cordwood construction, the Type of wood used is an important consideration. Softwoods such as pine, spruce, and coniferous species are commonly used due to their lower density and superior insulative properties compared to hardwoods like oak and elm. The softer the wood, the more insulative it is, making it ideal for cordwood walls. The choice of wood also depends on the availability of resources in a particular area. For example, in the case of cottonwood logs used in the construction of the cordwood cottage, they were readily available on the property, making them a convenient and sustainable building material.

The Importance of Lime-Based Mortar

In cordwood construction, the type of mortar used is crucial to the structural integrity and performance of the walls. Lime-based mortar is a popular choice for several reasons. Unlike Portland cement-based mortar, lime mortar has a slower setting time, allowing for more flexibility during the construction process. It can be easily worked and tooled to achieve the desired result. Lime mortar also offers self-healing properties, as it can accommodate the natural movement and expansion and contraction of the logs without cracking or deteriorating. This makes lime mortar a reliable and Durable choice for cordwood walls.

The Benefits of Using Lime-Based Mortar

Using lime-based mortar in cordwood construction comes with numerous benefits. One of the primary advantages is its affordability compared to Portland cement-based mortar. Lime mortar has a lower energy footprint as it does not require extremely high temperatures for its production. Additionally, lime mortar has a higher degree of breathability, allowing moisture to escape from the walls and preventing the buildup of condensation. This breathability is crucial for maintaining the longevity of the walls and preventing the growth of mold or mildew. Overall, lime-based mortar offers a sustainable, long-lasting, and aesthetically pleasing option for cordwood construction.

Preparing the Lime Mortar

To prepare the lime mortar used in cordwood construction, a combination of lime putty and sand is required. Lime putty is created by slaking lime with Water and allowing it to hydrate for at least 48 hours. This slaked lime putty is then mixed with sand in a specific ratio, typically five parts sand to one part lime putty. The mixture should have a consistency similar to soft cream cheese. Water can be added to adjust the consistency as needed. The lime mortar needs to be mixed thoroughly, ensuring all the ingredients are evenly distributed. The lime mortar can be made ahead of time and covered with water to keep it pliable until ready for use.

Preparing the Log Rounds

Before building a cordwood wall, the log rounds need to be prepared. The log rounds should be sourced from softwood trees, ensuring their insulation properties. Limbs and nubs should be knocked off the log rounds to facilitate easier installation and tighter grout joints. It is helpful to have a variety of log sizes, including small diameters for creating tighter grout joints and larger diameters for filling larger gaps. Each log round should be cut to the desired length of the wall, typically nine inches for a standard thickness. Using a square guide, the log rounds can be cut to ensure square and Parallel surfaces.

Installing the Sawdust Insulation

Sawdust insulation is an essential component of cordwood walls, providing additional thermal insulation and acting as a deterrent to pests. Before installing the sawdust insulation, a layer of mortar is applied to the wall, leaving voids in between. These voids are then filled with sawdust that has been mixed with dry, hydrolyzed lime powder. This mixture of sawdust and lime helps prevent pests, such as mice and insects, from nesting in the walls. The sawdust insulation adds an extra layer of insulation, enhancing the energy efficiency of the cordwood walls. Care should be taken to ensure even distribution of the sawdust insulation throughout the wall.

Building a Cordwood Wall

Building a cordwood wall involves the careful placement of log rounds on the mortar bed. Each log round is positioned on the mortar and spaced apart to create grout joints. The mortar fills the gaps between the logs, providing stability and support to the structure. It is essential to work in small sections, ensuring each log round is securely set in place before moving on to the next. As the wall progresses, sawdust insulation is added to the voids between the log rounds. This process continues until the desired Height and length of the wall are achieved. Building a cordwood wall requires Attention to Detail and precision for optimal results.

Pros and Cons of Cordwood Construction

Like any construction method, cordwood construction has its pros and cons. Some of the advantages of cordwood construction include its thermal mass, energy efficiency, use of sustainable materials, and aesthetic appeal. Cordwood walls provide excellent insulation and can help lower heating and cooling costs. Additionally, the use of natural materials like logs and lime-based mortar makes cordwood construction a sustainable choice. However, cordwood construction can be time-consuming and labor-intensive. It requires careful planning, preparation, and attention to detail. The availability of suitable wood and the need for maintenance can also be considerations. Despite these potential challenges, cordwood construction offers a unique and sustainable building option.

Conclusion

Cordwood construction is an innovative and environmentally friendly building method that provides both beauty and energy efficiency. By combining logs with lime-based mortar and sawdust insulation, cordwood walls offer excellent thermal mass and insulation properties. With proper planning, preparation, and attention to detail, a cordwood cottage can be a striking and sustainable structure. Whether you are interested in sustainable building practices, a DIY enthusiast, or simply curious about alternative construction methods, cordwood construction offers an exciting option to explore. By leveraging the natural resources available and utilizing the unique properties of cordwood, you can create a beautiful and eco-conscious living space.

Highlights:

• Cordwood construction combines logs, lime mortar, and sawdust insulation.
• It offers excellent thermal mass and energy efficiency.
• Lime-based mortar is advantageous due to its self-healing properties and slower setting time.
• Cordwood walls can be made using readily available softwoods like pine and spruce.
• Sawdust insulation prevents pests and enhances insulation.
• Cordwood construction is sustainable and aesthetically pleasing.
• Building a cordwood wall requires careful planning and attention to detail.
• Cordwood construction offers a unique and environmentally friendly building option.

FAQ:

Q: Is cordwood construction energy-efficient?

A: Yes, cordwood construction offers excellent thermal mass and insulation properties, resulting in energy-efficient buildings.

Q: Can any type of wood be used in cordwood construction?

A: Softwoods such as pine and spruce are commonly used in cordwood construction due to their superior insulative properties.

Q: Is lime mortar better than cement-based mortar for cordwood construction?

A: Lime mortar offers several advantages, including self-healing properties and a slower setting time, making it more suitable for cordwood walls.

Q: How long does it take to build a cordwood wall?

A: The time required to build a cordwood wall depends on the size and complexity of the project. It can take several days or even weeks to complete.

Q: Is cordwood construction suitable for all climates?

A: Cordwood construction can be adapted to various climates, but additional insulation may be required in extreme cold or hot regions.

Q: What are the maintenance requirements for cordwood walls?

A: Cordwood walls require regular inspection and maintenance to ensure the integrity of the mortar and wood. Repointing mortar joints and sealing any gaps may be necessary over time.

Q: Can I build a cordwood cottage myself?

A: Building a cordwood cottage is a complex project that requires knowledge and skill. While it is possible to build one yourself, it is recommended to consult with experts and obtain proper guidance.