Silvertop Ash Decking

Silvertop Ash decking in 86 × 19 mm and 135 × 19 mm: a pale Australian hardwood with Janka hardness 9.7 kN and Class 2 durability above ground, rated for bushfire decking up to BAL-19 at this 19 mm thickness.

• Sizes: 86 × 19 mm and 135 × 19 mm
• Timber: Silvertop Ash (Eucalyptus sieberi), grown in NSW, eastern Victoria and north-east Tasmania; pale brown, sometimes with a pink tinge; about 820–850 kg/m³
• Durability: Class 2 above ground, which the Queensland Government rates at 15–40 years’ expected life
• Termites: the Queensland Government lists Silvertop Ash heartwood as not termite resistant, so keep the subframe termite-protected
• Movement: it has the highest shrinkage of our decking species, so keep to the recommended gaps and seal every face
• Bushfire: our 19 mm Silvertop Ash is rated for decking up to BAL-19; BAL-29 needs a thicker 22 mm board. For BAL-29 in 19 mm, choose Spotted Gum, Blackbutt or Merbau
• Joist spacing: 450 mm centres, as WoodSolutions recommends for decking; its deck design guide allows up to 500 mm for 19 mm hardwood, or 350 mm if the boards run at 45°
• Gaps: 3–4 mm between 86 mm boards and 4–5 mm between 135 mm boards at installation (WoodSolutions deck design guide)
• How much for a deck: a 20 m² deck needs about 140 lineal metres of 135 mm board or about 225 lineal metres of 86 mm, plus about 10% for offcuts
• Low decks: under 400 mm off the ground, WoodSolutions suggests 5–6 mm gaps and at least 40 mm between the deck and the house, for airflow
• Fixing: two fixings per board at every joist, at least 12 mm from edges and ends. Pre-drill this dense hardwood. Use stainless steel within 1 km of the coast or 1 m of a pool. See our decking screws
• Finishing: coat every face and cut end, ideally before fixing, then recoat at least once a year or as the oil maker directs (WoodSolutions); left bare, it weathers to silver-grey. Oils we stock: CUTEK CD50, Intergrain Universal Timber Oil or Sceney’s Timber Decking Oil
• At Greenhill: stocked at 170 Settlement Road, Thomastown, with pickup or delivery across Melbourne and regional Victoria. Compare species on our hardwood decking page.

Silvertop Ash decking: sizes, lengths and prices

Sold in random lengths, cut to suit. Prices are our website prices on 14 October 2026, per lineal metre; a 20 m² deck needs about 140 lineal metres of 135 mm board or 225 of 86 mm, plus 10% for cuts.

What Silvertop Ash decking is like

Silvertop Ash, Eucalyptus sieberi, is cut in eastern Victoria, southern NSW and north-east Tasmania, and is the lightest board in our range at about 850 kg/m³. It is pale brown, sometimes with a pink tinge, and straight-grained, so it reads as a pale, even deck. WoodSolutions puts its seasoned hardness at 9.7 kN, above Blackbutt and Merbau.

Its weak points are durability and movement. The Queensland Government tables rate the heartwood Class 2 above ground, the lowest in our decking range, and not termite resistant, and it has the highest shrinkage of our decking species, so it needs its gaps and a sealed back face. Priced right, it is a good deck for a dry, well-ventilated spot.

Where it suits

Use it for a raised, open deck that dries quickly and where you want a pale timber at a lower price than Blackbutt. Keep it off the ground, out of permanent shade, and away from garden beds. Bushfire: our 19 mm Silvertop Ash is rated for decking up to BAL-19; BAL-29 needs a 22 mm board, or Spotted Gum, Blackbutt or Merbau in 19 mm.

Fixing and finishing

Pre-drill, two screws per board per joist, 450 mm joist centres, and keep the full 4–5 mm gap because of the shrinkage. Oil all faces before laying, including the back and ends, and recoat each spring. Intergrain Universal Timber Oil or CUTEK Extreme CD50; screws in decking accessories.

The same timber for other jobs

• Blackbutt decking – the other pale board, Class 1 and BAL-29
• Hardwood decking – all six species side by side

Compare the species

Our decking timber comparison puts hardness, durability, bushfire rating and price per metre for all six hardwoods on one page; Merbau decking is the budget alternative.

Questions we get asked

How much does Silvertop Ash decking cost?

On our website on 14 October 2026, 86 × 19 mm is $8.95 per lineal metre and 135 × 19 mm $17.50 per lineal metre.

Is Silvertop Ash durable?

Class 2 above ground in the Queensland Government tables, a class below Spotted Gum, Blackbutt and Merbau, and the heartwood is not termite resistant. It lasts well on a raised deck that dries out; it is the wrong board for a damp, shaded one.

Is it BAL rated?

Our 19 mm boards are rated for decking up to BAL-19. BAL-29 needs 22 mm Silvertop Ash or one of the listed species in 19 mm.

Why does it move more than other decking?

Its shrinkage figures are the highest of our decking timbers (WoodSolutions: 10.6% tangential), so it gains and loses more width with the seasons. The standard gaps allow for it.

Pickup and delivery

Stocked at 170 Settlement Road, Thomastown, Mon–Fri 7 am–4:30 pm and Sat 9 am–1 pm. We pack and load it for you, or deliver across Melbourne and regional Victoria; delivery is quoted with the order. Call (03) 9465 9875 with your sizes and we will work out the lineal metres and the price.

Pick up from 170 Settlement Road, Thomastown. Stocked lines are usually ready the same day. Delivery across Melbourne and regional Victoria is quoted on the order; call (03) 9465 9875 for a price on your suburb.

All prices include GST. Flooring is priced per square metre, decking and dressed timber per lineal metre, framing and posts per length. Trade accounts get trade pricing on the site and at the counter: apply here.

Bring your room or deck sizes in, or call (03) 9465 9875, and we will work out boards, lengths, fixings and oil, with about 10% allowed for cuts.