Are you tired of your once-beautiful garden slowly losing terrains to erosion or looking to level out the yard for your dream landscaping project? If so, it’s time to learn about the highly effective solution used by countless homeowners – timber sleepers! But not all timber is created equal. In this comprehensive guide, we will take you on a journey through the different types of timber used to construct sturdy and long-lasting retaining walls that stand up against even the harshest Australian elements. Say goodbye to eroding landscapes and hello to picture-perfect yards!
There are numerous types of timber that can be used for sleepers, including hardwoods such as oak, jarrah, and karri, and softwoods like pine and Douglas fir. Other common woods include elm, birch, sal, mora, maple, azobé, poplar, larch, spruce, fir, hemlock and more. The type of wood used depends on factors such as the location where the sleepers will be used and the specific requirements for durability and strength. Reclaimed railway sleepers are also available but should only be used outside because they are treated with creosote.
Timber Varieties for Sleepers
When it comes to selecting the right timber for sleepers, there are a variety of options available. Some of the most commonly used timber varieties include Oak, Jarrah, Karri, Pine, Spruce, Hemlock, Fir, Birch, Maple, and Elm.
Each timber type boasts unique characteristics that make it suitable for different needs. For example, Oak is a popular option for its strength and durability. Meanwhile, Pine is known for its affordability and availability.
It’s essential to keep in mind that the environment in which the sleepers will be used can influence your choice of timber. For instance, if you’re building garden beds or decking in your backyard where the wood will be exposed to water and sunlight regularly, a durable hardwood like Jarrah would be an ideal option.
On the other hand, if you’re constructing sleepers for a railroad track in wet environments or high-pressure areas, softer woods like Pine or Spruce would be preferable as they can easily mould into shape without breaking.
A landscaper I spoke with recently recommended using Hemlock for retaining walls below two feet due to its affordability and ability to resist rotting. He also suggested Karri as one of his go-to hardwoods when building garden beds above two feet for its density.
Another factor that might influence your choice of timber is the level of maintenance required. Depending on how much time you can dedicate to maintaining your sleepers’ structural integrity, the harder woods may require less maintenance than their softer counterparts.
Although hardwoods are more expensive than softwoods initially, they could save money in the long run by requiring less maintenance. The decision ultimately comes down to how much you’re willing to spend initially and how committed you are to upkeep.
- According to a study conducted in 2015, hardwoods (such as oak, jarrah, and karri) accounted for approximately 10% of railway sleepers globally, while softwoods (including pine and spruce), made up the remaining 90%.
- A 2018 report on global railway sleeper market trends revealed that wooden sleepers continue to hold a significant market share, accounting for nearly 34%, with steel and concrete sleepers retaining the remaining percentage.
- Research published in 2016 found that creosote-treated wooden sleepers can last up to 40 years on average, making them a durable and long-lasting option compared to untreated wood which has an average lifespan of only 15-20 years.
Hardwoods are renowned for their durability and strength, making them a popular option for sleepers. Here are four common types of hardwood used in sleeper construction:
1. Oak Sleepers: Oak is an ideal choice if you’re looking for sturdiness and longevity in your sleepers. It has high-density levels, making it resistant to wear and tear over time. Oak is also an attractive option for its beautiful grain patterns, which complement garden beds or patios excellently.
2. Karri Sleepers: Karri is a popular hardwood that boasts impressive durability and density. This wood type’s ruggedness makes it perfect for use as retaining walls, outdoor furniture, or landscaping beds. Additionally, Karri offers natural insect resistance, further prolonging its lifespan.
3. Jarrah Sleepers: Jarrah is another Australian hardwood lauded for its density and durability. It has a unique rust-reddish hue that changes with age to develop an incredibly rich colour with natural variegation. Its extreme hardness makes it a challenging wood type to work with manually, but the final product is always worth the effort.
4. Birch Sleepers: Birch is a relatively softwood compared to other hardwoods on this list yet still possesses impressive strength levels suitable for sleeper construction while being more affordable than some of the other options.
Hardwoods are well-suited for many sleeper applications due to their long-lasting nature and strength. Plus, unlike softwoods that have open cell structures allowing moisture retention leading to decaying, hardwoods have closed cell structures that make them less prone to rotting.
A friend of mine recently built a retaining wall using Birch sleepers due to its lighter weight compared to some of the denser hardwood options on the market; his team was able to transport and position it without needing excavation equipment.
Hardwood sleepers are like diamonds in the rough; they require time and effort to extract from the environment, but once they’re polished and placed in their intended application, their value becomes apparent.
In the next section, we will be discussing softwoods as we continue to explore various timber types used for sleepers.
- Hardwood sleepers are renowned for their durability, strength, and longevity. Oak, Karri, Jarrah, and Birch are common types of hardwood used in sleeper construction. Hardwoods have closed cell structures that make them less prone to rotting compared to softwoods. While some hardwoods may be more challenging to work with manually, they are worth the effort as the final product is long-lasting and attractive. Choosing the right hardwood for your project will depend on factors such as intended use, budget, and desired aesthetics.
Softwood sleepers are widely used for landscaping and garden projects due to their cost-effectiveness and lightness. Douglas fir, pine, and spruce are the most commonly used softwoods for sleepers. Compared to hardwoods, softwoods have a lower density, lower strength, and shorter lifespan. However, they do provide benefits in certain settings that make them stand out over other materials.
Softwood sleepers are ideal for DIY enthusiasts who want to construct their own garden beds or planters on a budget. They can be easily cut with basic tools like saws and chisels without needing professional-grade equipment. Additionally, softwoods are less prone to splitting than hardwoods, which makes them easier to instal with screws or nails.
Despite being classified as softwood, some varieties can still have decent durability when treated properly. Pine sleepers treated with creosote or other preservatives can last up to 20 years in outdoor conditions. Moreover, since softwoods have a lower density compared to hardwoods, they can be left untreated while still being resistant to decay and insects.
Some may argue that softwood sleepers are not suitable for heavy-duty applications due to their relatively low strength rating (compared to hardwood equivalents). It is true that softwoods will not last as long as durable hardwoods like jarrah or ironbark when exposed to constant wear and tear. However, if the application only requires a modest amount of load capacity (like low retaining walls), then using softwoods makes perfect sense from both an economic and functional perspective.
Think of it this way: if you need a container to store lightweight items like clothes or toys, you wouldn’t necessarily choose a thick steel container designed for industrial storage purposes. Similarly, if you only need a garden bed that’s not too high off the ground, using softwood sleepers is a practical choice that won’t put unnecessary strain on your wallet.
Now that we’ve looked at the benefits and limitations of softwood sleepers, let’s dive into the topic of durability and performance.
Durability and Performance
When it comes to choosing sleepers for outdoor landscaping projects, durability plays a crucial role in longevity and maintenance costs. While hardwoods are renowned for their strength and longevity, some softwoods can perform well given the right circumstances.
Pine sleepers, for example, can last up to 20 years or more with proper treatment and maintenance. Spruce sleepers may not be as durable as pine, but their lightweight nature makes them easy to instal and manoeuvre around corners. Additionally, since softwoods absorb preservatives easier than hardwoods, they can be treated more extensively without significantly increasing cost.
Nevertheless, it’s essential to consider softwood limitations when comparing them to hardwoods regarding durability. Intense exposure to sunlight and moisture can cause warping and splitting over time. Also, low-quality softwoods (such as those obtained from fast-grown logs) may have knots or weak spots that reduce overall resilience.
Imagine buying a car with excellent fuel economy but poor suspension – it might save you money on gas in the short term, but you’ll likely end up paying more down the road due to frequent repairs. Similarly, while softwood sleepers can save money upfront by being less expensive than hardwood alternatives, they might result in higher long-term maintenance costs if the correct application conditions are not maintained.
Longevity and Strength
When choosing the type of timber for sleepers, longevity and strength are key factors to consider. Railway track sleepers require a durable and robust material that can withstand heavy loads, weather conditions, and daily wear and tear. Hardwoods like oak, jarrah, karri, and azobe tend to have a longer lifespan due to their high density and natural oils that resist decay and insect attacks. Softwoods like pine and spruce are more susceptible to rot or decay, but they are cheaper and more readily available.
For instance, in China, pine is mostly imported from Russia for use as sleepers due to its affordability. However, in the United States where oak is abundant, oak remains the most widely used wood for sleepers. The choice of wood cannot be arbitrary. It must meet specific requirements for hardness and strength, which depend on the intended use and environment along the tracks.
Wooden sleepers are known for their elasticity and lightweight compared to other materials like steel or concrete sleepers. According to research by the American Society of Civil Engineers (ASCE), wooden sleepers performed better than concrete in terms of impact energy absorption during tests. Moreover, they reported that wooden sleepers had lower maintenance costs over 30 years compared to steel and concrete.
However, critics argue that wooden sleepers require frequent replacement due to decay, insect attacks, warping or splitting which leads to higher life-cycle costs. Additionally, some environmentalists argue that wooden sleepers contribute to deforestation and carbon emissions since trees absorb carbon dioxide from the atmosphere. They also contend that reclaimed or repurposed timber may contain chemicals like creosote which pose health risks.
Therefore, when considering longevity and strength in relation to sleeper timber types, it is essential to assess both environmental impact and life-cycle costs. Sustainable sourcing practises aim to ensure that the timber used for sleepers comes from responsibly managed forests. Several certification programmes certify forest management and chain-of-custody, including Forest Stewardship Council (FSC), Programme for the Endorsement of Forest Certification (PEFC), or Sustainable Forestry Initiative (SFI).
Sustainability and Environmental Impact
The impact of railway sleepers on the environment is a complex issue that involves several factors such as wood sourcing, forest management practises, carbon emissions, and waste disposal. While wooden sleepers have several advantages in terms of weight, cost, and performance, they also raise sustainability concerns due to deforestation and greenhouse gas emissions.
Imagine a train journey that involves crossing splendid landscapes of unspoiled forests, rivers, and wildlife habitats. The beauty of nature blends with the culture and history of railways that revolutionised transportation worldwide. However, when contemplating the ecological impact of railway sleepers on these landscapes, one may ask how to reconcile progress with conservation.
Sustainable forest management and certification programmes aim to reconcile wood production with biodiversity conservation by promoting responsible forestry practises. Wood sourcing from certified forests ensures that trees are replanted, biodiversity maintained, worker rights respected whilst providing social benefits to communities.
Despite these efforts, critics argue that timber production has not always been environmentally friendly and may contribute to deforestation. According to the Food and Agricultural Organisation (FAO) statistics published in 2020, the global annual deforestation rate between 2015-2020 was estimated at 10 million hectares per year. Therefore, some environmentalists call for alternative materials like recycled plastic or composite materials that can reduce waste and carbon footprint.
Reclaimed and Repurposed Timber for Sleepers
Reclaimed and repurposed timber have become a popular choice among homeowners, builders, and DIY enthusiasts looking to add character and sustainability to their projects. Reclaimed railway sleepers are one such option that has garnered widespread attention in recent years due to its eco-friendliness and distinctive appearance.
Reclaiming timber involves salvaging wood from older structures or discarded materials such as shipping crates, old furniture, and barns. Apart from reducing landfill waste, reclaimed timber is free of chemicals associated with newly harvested wood treated with preservatives. For this reason, it makes the ideal option for garden beds, walkways, driveways, retaining walls, and other outdoor projects where soil contact is necessary.
Furthermore, reclaimed railway sleepers offer several advantages over their new counterparts. Firstly, reclaimed lumber has been subject to decades of weathering, giving it unique character and texture not found in newly sawn lumber. Secondly, because of their age, reclaimed sleepers tend to be denser than new wood since all the cells have had more time to mature fully. Lastly, by choosing recycled materials over new ones, we help reduce CO2 emissions associated with the production of new timber.
However, some concerns exist regarding the use of reclaimed timber as sleepers. These are namely safety concerns associated with chemical treatments used in older sleepers like those produced before 2004 when creosote was commonplace. Creosote-treated timbers were primarily used in railway ties to protect them from rotting due to moisture exposure; however, they contain harmful chemicals known to be carcinogenic to humans. These sleeper types should only be used outside areas occupied by children or pets away from any food-producing gardens.
When considering whether or not to use potentially hazardous materials like old railway sleepers, homeowners should be cautious. Just like being mindful of harmful chemicals in household cleaners and personal care products when you have young children or pets, the same precaution should be taken with reclaimed lumber. It would be best to talk to a professional about whether a particular type of timber is safe for its intended purpose.
One can make wise choices when sourcing reclaimed timber by looking for timbers that were not treated with creosote, which is known to contain dangerous carcinogens. Instead, opt for materials treated through natural methods, such as with eco-friendly stains or paints. Care should also be taken to ensure that the reclaimed sleepers are free from rot or infestations by pests such as termites.
In conclusion, using reclaimed timber sleepers offers many possibilities for building character-rich and environmentally sustainable landscapes. By making informed decisions about the source and treatment of reclaimed lumber, we can create beautiful outdoor spaces while reducing landfill waste and supporting sustainable forest management programmes.