Choosing the right timber for outdoor projects is one of the most important decisions you can make as a builder, landscaper, or homeowner. The timber you select affects the appearance, lifespan, maintenance needs, and cost of your project. Selecting the wrong product can lead to premature damage, warping, and even costly replacements.
ATS Building Products, supply outdoor timber to customers across Australia, with warehouse locations in Sydney, Melbourne, Brisbane and Adelaide. Our range includes treated pine, and hardwood, all suitable for different types of outdoor construction. Whether you are building a new deck, a pergola, or a fence, the right choice of timber will help you get the best results and keep your project looking great for several years.
What to Look For in Outdoor Timber
Outdoor timber has to handle a lot. Unlike internal framing timber, it is constantly exposed to moisture, UV rays, wind, and pests. The main considerations when choosing timber for outdoor use are:
- Durability – Will it withstand years of weather exposure without losing strength or structure?
- Termite resistance – In many parts of Australia, termites are a serious concern for outdoor structures.
- Treatment class – The treatment class determines where the timber can be used. H3 is ideal for above-ground outdoor applications, while H4 is used for timber that will be in direct contact with the ground.
- Appearance – The colour, grain, and finish will impact the look of your project. For visible structures like decking and pergolas, aesthetics are important.
- Maintenance requirements – Some timbers need regular sealing or staining, while others require minimal upkeep.
If you want more background on treatment classes, our article on H2 vs H3 Treated Timber explains the basics in more detail.
Best Timber for Decking
Decking is one of the most common uses for outdoor timber in Australia. The choice often comes down to treated pine or hardwood, each with its own strengths.
Treated Pine Decking (H3)
H3 treated pine is a practical, budget-friendly choice for decking. It is easy to work with, available in a wide range of lengths and profiles, and can be stained or painted to achieve different finishes. Because it is treated, it resists termites and decay, making it suitable for most climates. For builders, it is also lightweight and fast to install.
Hardwood Decking
Hardwood species such as Merbau and Spotted Gum are popular for their natural beauty and long lifespan. Hardwoods tend to have a richer colour and a more premium appearance, which makes them ideal for high-end residential decks. They are also extremely durable, with natural resistance to decay and insect attack. The trade-off is a higher cost and the need for occasional oiling or sealing to maintain their colour.
Explore our decking timber range to find options that suit your project’s style and budget.
Best Timber for Pergolas
Pergolas are both decorative and functional, providing shade and creating an inviting outdoor space. The timber needs to be strong, stable, and resistant to the elements.
H3 Treated Pine
For above-ground pergola frames, H3 treated pine is a reliable choice. It offers the durability and termite resistance needed for outdoor conditions while being easy to cut and assemble. Its light colour makes it easy to paint or stain to match the surrounding structures.
Construction / Framing Timber
If you need longer spans or extra structural strength, construction-grade timbers are worth considering. These engineered products are designed for strength and stability, making them suitable for larger pergola designs.
Visit our construction timber page for more information on products that can be used for pergola framing.
Quick Outdoor Timber Guide
| Application | Recommended timber | Treatment class | Why it works |
|---|---|---|---|
| Decking |
Treated pine decking or hardwood |
H3 | Resists decay and termites. Suitable for above-ground exposure. Easy to work with and finish. |
| Pergolas | H3 treated pine framing. Construction timber for longer spans (see construction timber) | H3 | Durable and reliable for outdoor structures. |
| Fences | H3 treated pine rails and palings. Hardwood posts where longer life is desired | H3 for rails and palings. H4 for in-ground posts | Cost-effective, widely available, and long-lasting when installed and maintained correctly. |
External Guidance
If you want more general guidance on timber selection, the WoodSolutions website is an excellent resource for understanding species, treatments, and outdoor applications.
Summary
Selecting the right timber for your outdoor project will ensure it looks great and stands the test of time. At ATS Building Products, we can supply treated pine and hardwood, suitable for a wide range of outdoor applications. Call our team today for expert advice and competitive pricing on outdoor timber for your next project.
FAQs
For posts in direct contact with the ground, H4 timber is better suited. H3 timber is ideal for above-ground fence components like rails and palings.
When installed correctly and maintained with regular oiling or sealing, hardwood can last decades outdoors thanks to its density and natural resistance to decay.
H3 treated pine is a common choice for pergola frames due to its durability and resistance to pests. Construction timber can be used if extra strength or longer spans are needed.
Yes. H3 treated pine is designed for above-ground outdoor use and provides reliable protection against decay and termites, making it a popular choice for decks.