Last Modified: April 1, 2024

Rubber Mulch for Playgrounds

A Game-Changer in Play Safety

Unbonded rubber playground chips around play equipment

By Ben Parrot - Landscape Gardener & Amateur Geologist

Overview

Playground surfacing has significantly evolved over the years, with harm-minimisation and durability the foremost concerns. Along with wet pour rubber, rubber mulch playground have become a popular choice. Its cushioning ability as a flooring has helped to create recreational areas that have a significantly reduced risk of injury, and the severity, particularly in the event of a fall.

In this article, we take a deeper look into one of the two most common play area types utilising a playground surfacing based on rubber chippings, made from manufactured from recycled tyres. They are known as rubber mulch playgrounds.

Key Takeaways

  • Loose Fill or Bonded: Play area mulch is available to lay loose or may be installed using a resin.
  • Best Safety Surface: Rubber mulch flooring minimises injury risks and provides slip-resistance in recreational areas.
  • Durable and Low Maintenance: Rubber chipping surfaces are generally very hard-wearing and require little maintenance.
  • Long-term Risks: There are concerns around potential risks to health and the environment from the leachate of rubber chippings.
Child in a play area image by anialaurman from

Image by anialaurman from Pixabay

Two Types: Loose Fill vs. Bonded

There are two main ways that shredded rubber playground mulch flooring is installed. When installed in its loose form, mulch rubber is a durable and low-maintenance material when used as a rubber playground fill. The other type is a bonded rubber mulch. It is laid using a resin binder, making it more ideal as a rubber ground cover for playgrounds and pathways.

However, both are capable of providing the maximum critical fall height protection, and both come in a range of colours. Let's investigate the differences.

Loose Fill Products

Rubber safety mulch is a low-maintenance, highly durable substitute to traditional grass or wood and bark chips, when installed in a loose form. When comparing fall safety protection, a rubber mulch playground surface is far superior, if laid at the correct depth. Rubber chippings' general resistance to decomposition and ability to reduce dust and mitigate muddy footprints, especially in the wet, are also considered desirable.

Whilst it requires slightly more maintenance that it's bonded counterpart, it's more-affordable. The process of laying is also far more DIY-friendly.

What Is Bonded Rubber Mulch

Effectively, it is the binding together of rubber playground chips, utilising a polyurethane resin, to create a surface that is not only more durable but also remains consistent throughout.

The Advantages of Bonded Rubber Mulch

Bonded rubber mulch has become a mainstay of modern playground surfacing. Unlike a loose fill rubber surface, bonded mulch stays in place, providing a safety surface that isn't prone to change over time or due to weather.

Like its close counterpart, wet pour, it provides the highest level of critical fall height protection which can be counted on, no matter what. Similarly, bonded rubber allows for customisation and the fixture of designs, unlike with loose fill products.

Wet Pour Safety Surfaces vs. Bonded Rubber Mulch

Rubber wet pour surfaces are made by binding tiny rubber nuggets for playgrounds into a smooth finish, while bonded rubber mulch has a more textured surface.

Multicoloured loose fill shredded rubber. Jpg
Grass next to bonded rubber safety mulch. Jpg
Wetpour child safety playground

Benefits of Rubber Mulch

Critical Fall Height Protection & Slip Resistant Properties

The higher the equipment, the more crucial the need for fall protection. Rubber grass excels in offering a high critical fall height, meaning it can cushion falls from greater heights than many alternative surfaces. This superior cushioning drastically reduces injury risk, ensuring a safer play environment.

Rubber mulch also reduces slipping. With it's natural qualities and a granulated texture, traction is increased, making rainy, wet days less hazardous for play.

A Natural Look With Safety

While a rubber chips playground surface can come in various colour coating options to complement most needs, those manufactured using the pigments of natural colours can also be sourced for creating a more natural look.

Rubber Wood Chips For Playground Surfacing?

Using rubber bark is another way to blend in a more natural look, with the look of traditional bark mixed with the safety and resilience of rubber chippings. Rubber bark chippings are less attractive to pests, and they don't decompose, which also makes them lower maintenance.

An Environmentally Friendly Surface Option

The green choice to opt for a recycled rubber surfaces has a mixed benefit to the environment. Whilst it does reduce tyre waste and consume less energy than other alternatives, the fall safety aspect has to be given the greatest weight. However, there are known environmental costs which make it a bit less 'eco-friendly' than the marketing would suggest.

Skip full of tyres for recycling. Jpg

Need to work out how much rubber mulch your play area or mulching  project needs? Try our free calculator.

Ensuring Your Play Areas Safety Is Covered

Surface material is pivotal in determining a playground's safety. Due to rubber's inherent shock-absorbing quality, it provides a protective barrier against falls. Also, its permeability aids in fast water drainage, minimising puddles and slippery zones.

Playground standards exist for a reason. In commercial areas, or public parks, there are more detailed requirements, but it as a minimum, the supply of rubber chippings meets the BS EN 1177 standard of a high quality product. If the product does not meet the safety requirements, it should not be used. We also recommend seeking this standard for ANY installation.

Maximum Safety Means The Correct Footwear

Ensuring children are wearing the appropriate shoes is vital to safety, as it can ensure optimal grip and protection from unexpected pieces of wire which may surface in the installation.

Bonded rubber mulch running track. Jpg

Considering The Long-Term Risks

While rubber mulch can offer advantages, especially in terms of safety and traction on playgrounds, it's essential to acknowledge the legitimate concerns that often receive insufficient attention from those who stand to benefit most.

  • Toxicity Concerns: As rubber chippings degrade, it releases various chemicals, primarily heavy metals like aluminum, cadmium, chromium, molybdenum and selenium. It also emits 2-Mercaptobenzothiazole (MBT) and polyaromatic hydrocarbons (PAHs), both of which have demonstrated adverse impacts on human health and the environment.
  • Impact on Aquatic Life: Research conducted at Bucknell University has shown that the leachate can be harmful to algae, zooplankton, snails, and fish, cautioning against its use near ponds or water bodies.
  • Excessive Zinc: Rubber chippings contains high levels of zinc from its manufacturing process, and excessive levels can be detrimental to plants, posing challenges for remediation.
  • Leachate Emissions: Studies indicate that rubber can emit gases that may be inhaled, particularly when the material heats up, potentially leading to volatile organic compounds (VOCs) leaching into the air.
  • Lack of Decomposition: Rubber, being non-organic, does not naturally decompose, contributing no organic matter to the soil and posing difficulties for removal.
  • Heat Retention: Under direct sunlight, it can become excessively hot, making playgrounds uncomfortable for children and pets.
  • Flammability: Rubber is highly flammable and burns hotter and faster than wood, making it very difficult to extinguish. It is absolutely not recommended for use in high fire risk areas.

There are numerous scientific studies highlighting the potential risks. Besides concerns about transparency and rigor in the marketing of rubber chippings, generally, the lack of comprehensive, long-term studies on its usage is another issue.

Loose fill rubber outdoor play area. Jpg

Choosing the Right Playground Surfacing

There are varied surfacing and coating options, from loose fill, to wet pour and bonded rubber mulch. Budget, area size, play equipment height, and aesthetic preferences are all part of the decision.

Comparison to Wood Bark Chippings

Wood bark chippings don't offer the same type of critical fall protection that rubber chippings do, and they also deteriorate over time, becoming a haven for pests. Wood chips used in landscaping are generally considered safe; however, there can be some risks associated with toxicity in certain circumstances.

Chemically Treated Wood

Chips made from chemically treated wood, such as pressure-treated lumber or waste shipping pallets, do contain many toxic substances like arsenic, chromium, and copper. They are used to protect the wood from rot and insects. Use of them in playgrounds where children come into contact with them can be a concern. It's always safest to be certain of the wood's origins before choosing them for your play area.

If you are seeking a similar aesthetic, rubber play bark might be worth reading about.

Maintenance Free

While the initial costs are much higher, the ultimate cost can be deceptive. Aside from the level of protection against serious injury, you should also consider any long-term savings from reduced maintenance, repairs, and top-ups of soil or wood chip.

Bonded rubber safety surface for playgrounds

Summary

In summary, rubber mulch for playgrounds is an innovation that seamlessly blends a new level of safety together with durability, aesthetic versatility, and low maintenance. As a product born from recycled tyres, it not only helps to reduce landfill waste but also offers a superior surface that minimises injury risks.

However, while rubber is claimed exclusively an environmentally friendly surface with great safety benefits, there are legitimate concerns related to its toxicity, emissions, and flammability. A lack of long-term studies warrants careful consideration when using rubber mulch, especially in environments where use could pose significant risks to users and ecosystems.

Rubber mulch is a stand out for the safety of modern playgrounds, parks, and recreational areas. Seeking further information so that you can balance the safety with environmental concerns should be a priority in decision-making regarding its use.

Swing with red rubber mulch chippings image by manfred richter from

Image by Manfred Richter from Pixabay

FAQs

Is rubber mulch safe for playground?

It is a matter of some debate! Rubber mulch is marketed to be non-toxic, cushioned surface, that drastically reduces injury risks. However, there are some serious concerns. Regular quality checks and stringent manufacturing standards help to ensure safety credentials.

What is the downside of rubber mulch?

Aside from the environmental and health concerns, mentioned above, rubber mulch has a higher initial cost than traditional materials. However, considering its longevity and minimal maintenance along with fall safety is important when making a decision.

Should you put sand under rubber mulch?

It's optional. While rubber mulch can be laid over to create a compacted base, adding sand can provide an additional layer of cushioning, especially for very high play equipment.

What is the difference between playground mulch and rubber mulch?

Playground mulch generally refers to wood chips or organic materials used for play areas. Rubber mulch, on the other hand, is crafted from recycled tyres, boasting superior durability and a range of safety features.

Are rubber bark chippings the same as wood chips?

Rubber bark chippings are not the same as wood chips; they are made from recycled rubber materials as an alternative to traditional wooden chips.

There are many wonderful types of decorative chippings worth considering for your next landscaping project. Check out them out!

About the author 

Ben Parrot is a landscape gardener and amateur geologist. He is the founder of Outdoor Aggregates, with the mission to create the first encyclopaedia for decorative aggregates. From natural stone through to decorative bark, these aggregates are critical to garden and landscape design, universally.

The problem: There isn't any place where all the different types of decorative landscaping materials and construction aggregates can be found, nor are the specifications of each type readily available. So, enriched by his extensive experience, and inspired by the timeless elegance and raw beauty of stone and rock, etched by nature's artistry over millennia, Outdoor Aggregates was born.