Selecting the right timber is one of the most important steps in any building or landscaping project. The timber you choose will determine how long your project lasts, how much maintenance it needs, and how much you spend over time. Whether you are a builder, landscaper, or DIY renovator, a clear checklist will help you make the right decision.
At ATS Building Products, we supply a wide range of timbers across Australia, with warehouses in Sydney, Melbourne, Brisbane and Adelaide. From treated pine to engineered LVL, we can help you choose the right material for decking, pergolas, fences, and more.
Step 1: Identify Your Project
The first step in choosing timber is to match the product to the job. Decking, fencing, pergolas, framing, and formwork all have different requirements. For example:
- Decking needs timber that can resist weather and termites.
- Pergolas need above-ground durability with enough strength to span longer distances.
- Formwork requires smooth-faced ply such as formply to deliver a clean finish.
Step 2: Consider Exposure and Environment
Think about where the timber will be used:
- Above ground vs in-ground: Timber in contact with soil needs a higher level of treatment than timber that is raised.
- Climate: Australia’s diverse climates mean moisture, heat, and termites all need to be factored in.
Step 3: Choose the Right Treatment Class
Treatment classes tell you where timber can safely be used:
- H2: Indoor, above ground. Protected from the weather.
- H3: Outdoor, above ground. Resistant to weather and termites.
- H4: In-ground contact. Suitable for posts, sleepers, and garden edging.
For a full guide, see our article on H2 vs H3 Treated Timber.
Step 4: Look at Timber Grades and Stress Ratings
Timber is graded for strength and stiffness. Grades such as MGP10 indicate the timber’s performance under load. Higher grades can handle heavier structural requirements. While you do not need to calculate load capacity yourself, understanding that stronger grades exist will help you choose appropriately for frames, joists, or beams.
Step 5: Think About Durability and Species
Different timber species and types perform differently:
- Treated Pine: Affordable, versatile, and widely available. Suitable for outdoor use when treated to the right class.
- Hardwood: Naturally durable and offers a premium finish, ideal for visible areas like decking.
- Engineered Timber (LVL, T-studs): Designed for consistent strength and stability, with fewer defects and longer spans.
Step 6: Size and Length Requirements
Getting the right size is just as important as choosing the right type. Bearers, joists, and posts need to meet span and load requirements. Longer lengths can reduce joins, while the right thickness will determine how much weight the timber can handle.
See our Construction Timber range for details on common sizes and availability.
Step 7: Budget and Availability
Cost plays a role in every project. Treated pine is generally the most cost-effective option, while hardwoods and engineered products come at a premium but may reduce replacement or maintenance costs in the long run. ATS maintains consistent stock levels to help keep your projects on schedule.
Timber Checklist Table
| Project type | Recommended timber | Treatment class | Why it works |
|---|---|---|---|
| Decking | Treated pine decking or hardwood | H3 | Resists decay and termites, suitable for outdoor exposure above ground |
| Pergolas | H3 treated pine framing or LVL | H3 | Durable and termite resistant, LVL provides extra strength for longer spans |
| Fences | H3 treated pine rails and palings, hardwood posts | H3 for rails/palings H4 for in-ground posts |
Affordable and widely available, with added lifespan when hardwood is used for posts |
| Framing | Construction timber or engineered LVL | H2 or H3 | Strong and reliable for internal and external frames, available in multiple grades |
| Formwork | Formply and LVL formwork beams | N/A | Smooth, reusable surfaces for clean concrete pours |
Choosing the right timber is about more than cost. By following this checklist and considering treatment class, grade, durability, and size, you can select the best option for your project. The right decision will save you time, reduce maintenance, and ensure long-lasting results.
At ATS Building Products, we supply decking, framing, formwork, engineered timber, and more. Call our team today for expert advice and competitive pricing on timber for your next project.
Frequently Asked Questions
Refer to the span and load requirements for your project. Larger sections are required for longer spans or heavier loads. Our construction timber range provides common sizes.
Treated pine is affordable, versatile, and easy to work with. Hardwood is denser, naturally durable, and provides a premium finish, but comes at a higher cost.
Yes. H3 treated timber is designed for above-ground outdoor use and offers protection against termites and decay.
Check that the timber is the right type for your project, the correct treatment class, an appropriate grade, and available in the size you need.
Refer to the span and load requirements for your project. Larger sections are required for longer spans or heavier loads. Our construction timber range provides common sizes.
Treated pine is affordable, versatile, and easy to work with. Hardwood is denser, naturally durable, and provides a premium finish, but comes at a higher cost.
Yes. H3 treated timber is designed for above-ground outdoor use and offers protection against termites and decay.
Check that the timber is the right type for your project, the correct treatment class, an appropriate grade, and available in the size you need.