External Treated H3
External H3 and H4 Treated Pine for Decks, Posts and Framing
Building outdoors? External treated pine is the cost-effective timber for decks, pergolas, posts, cladding, and framing that lives in the weather. H3 treatment protects above-ground exterior timber against decay, borers, termites, and fungal growth, so pine that would rot untreated lasts for years outside. We carry the full external treated range across structural, decorative, and specialist lines, from framing and joists to primed cladding and bushfire-rated pine.
The External Treated Range
Different outdoor jobs need different timber, so start with the application. For load-bearing outdoor framing, structural treated pine H3/H4 covers bearers, posts, and framing. Laying a deck? Everjoist H4 treated pine and Extreme Joist H4 are built for deck substructure in ground-proximity conditions, and treated pine stringers carry the treads.
For finished surfaces, Design Pine H3 is primed and ready to paint for fascia, cladding, and trim, and treated H3 hardwood suits heavier outdoor work. Building in a bushfire zone? FLAMEfixx BAL 40 pine meets BAL-40 bushfire construction requirements.
Choosing the Right Treatment Level
Pine treatments run from H1 to H6: the higher the number, the tougher the protection against moisture, weather, and insects. H3 is the standard for above-ground external use, resilient against moderate decay, borers, termites, and fungal growth, ideal for decks above ground, posts, cladding, and outdoor framing. It can be stained or painted to finish.
Where timber sits in or near the ground, or in constant moisture with poor drainage, H3 is not enough. For those conditions step up to H4 (ground contact, used in the Everjoist and Extreme Joist lines) or higher. If you are unsure which level your job needs, our team can point you to the right one. For internal framing kept dry, see structural pine H2.
Serving Sydney Tradies and Renovators
- Trade pricing and bulk quantities: Competitive rates on volume orders. Call 1300 554 775 for trade and project pricing.
- Delivered to site across Sydney: Sydney, the Blue Mountains, Wollongong, and the Central Coast.
- The full external treated range: Structural, decking joists, primed Design Pine, hardwood, and BAL-40 bushfire pine in one place.
- Australian-owned family business: Western Sydney based. Real people, real stock, real advice.
Whatever the outdoor job calls for, we’ve got the treated pine.
Call 1300 554 775 or request a quote online and our team will help you match the timber and treatment to your job.
Frequently Asked Questions
What is H3 treated pine used for?
Above-ground outdoor work: decking above ground, pergolas, posts, cladding, fascia, and external framing. H3 protects against decay, borers, termites, and fungal growth.
What is the difference between H3 and H4 treated pine?
H3 is for above-ground exterior use. H4 is rated for ground contact and damp, in-ground conditions, which is why deck bearers and joists close to the ground use H4. Use H3 above ground, H4 in or near the ground.
Can H3 treated pine be painted or stained?
Yes. H3 treated pine can be stained or painted to suit your finish. Primed Design Pine H3 comes ready to paint.
What treatment level do I need for a deck?
Deck framing and joists near the ground need H4 (ground contact), while above-ground deck components can use H3. For a full deck, most builders use H4 for the substructure.
What is BAL-40 treated pine?
FLAMEfixx BAL 40 pine is treated pine that meets BAL-40 bushfire attack level requirements for building in designated bushfire-prone areas.