H4 Treated MGP10 Pine Framing Now Available on the Sunshine Coast
We’re excited to announce that MGP10 Pine Framing is now available in H4 treatment – giving local builders a stronger option for close to ground and other high-hazard applications.
With the Sunshine Coast’s humidity, heavy rainfall and high termite risk, choosing the correct hazard class for your timber is critical to long-term performance.
When Is H4 Required?
Timber treatment in Australia follows the AS 1604 standard (by Standards Australia), which sets out hazard classes based on exposure risk to attack by biological agents like insects and fungus.
H4 treatment is required when timber is:
- In contact or embedded in soil or concrete
- Within 150mm of the ground, especially if in a poorly ventilated setting
- Exposed to frequent or prolonged wetting
- Used in high termite risk areas
H4 is designed to resist:
- Severe decay
- Termite attack
- Fungal deterioration
Typical uses include:
- Deck and pergola posts
- Fence posts
- Retaining wall structures
- Landscaping timbers
- Ground-level framing
For very low decks (especially under 400mm above ground), moisture management and durability become even more important. Guidance from Timber Queensland highlights the need for proper ventilation, drainage and appropriate treatment levels in these situations.
Why H4 Pine Makes Sense Locally
Until recently, if you needed H4 treated structural timber, you were limited to unseasoned hardwood, with treated pine only available in H2 (internal) and H3 (external, well above ground).
Now, H4-treated, MGP10 pine is available and provides:
✔ In-ground capability
✔ Strong termite protection
✔ Cost-effective alternative to hardwood
✔ Consistent structural grading
✔ Readily available supply
For Sunshine Coast builds – particularly decks, landscaping and ground-level structures – H4 offers added peace of mind in our coastal, high-humidity climate.
Available Sizes
| Size (mm) | 3.6 m | 4.8 m | 6.0 m |
| 70 × 45 mm | ✓ | ✓ | ✓ |
| 90 × 45 mm | ✓ | ✓ | ✓ |
| 140 × 45 mm | – | ✓ | ✓ |
| 190 × 45 mm | – | ✓ | ✓ |
Best Practices for Long-Term Performance
Even with H4 treatment, good building practice is essential.
Ensure Proper Drainage
- Grade soil away from structures
- Prevent water ponding around posts
- Use gravel backfill where appropriate
- Consider a moisture barrier under low decks
Maintain Ventilation
- Keep subfloor and deck perimeters open
- Avoid trapping moisture with landscaping
Reseal All Cuts
Any cuts, drill holes, or notches should be treated with a suitable preservative reseal product to maintain protection.
Use the Right Fixings
Use hot-dipped galvanised or stainless-steel fixings for exterior applications.
Avoid moisture traps
Don’t encase posts in concrete above ground. Use flashing at ledger connections.
Timber Queensland provides valuable resources for decks installed close to or on the ground, which you can access via our resources page.
Not Sure If You Need H4?
If your project is:
- Close to the ground
- In contact with soil
- In a damp or poorly ventilated area
H4 is often the safer long-term choice.
Talk to our team about selecting the right treatment level for your Sunshine Coast project – and ask us about our new H4 pine framing range now in stock.
