Blackbutt

Blackbutt is straightforward to sand and rewarding to finish. It is hard enough — Janka around 9.1 kN dry — that a normal grit sequence of 40, 60, 80 and 100 (or 120) works without drama. Move up in progressive steps; skipping grits shows in the final coat as fine scratches under raking light.

On a 30-year-old Peninsula Blackbutt floor, we usually start with 40 or 60 grit depending on how much of the old coating is left. If the floor was previously finished with oil-based polyurethane, expect a slightly heavier first pass to cut the amber film cleanly before you reach raw timber.

Cut rate is moderate. The timber is dense so the drum sander will not chew through it the way it does on pine. That is a feature, not a limitation: you have more time to control each pass and less risk of dishing.

Tear-out risk is low. Blackbutt's straight grain sands cleanly with almost no lifting fibres. The edger tends to leave a slightly darker margin at the wall line because it cuts differently to the belt sander — blending that back in with a palm sander before the first coat is standard practice, not a fault of the timber.

Peninsula homes are the perfect proving ground for Blackbutt. It is coastal-suitable — dense enough to shrug off humidity swings between damp winters and dry summers, hard enough to handle sand tracked in from the beach, and UV-stable enough to hold its colour under the big north-facing windows most Peninsula houses have.

We see Blackbutt in almost every Peninsula suburb, but especially in the postwar hardwood pockets: Rosebud, Rye, McCrae, Frankston, Seaford. The shacks and modest houses built in those areas through the 1950s and 1960s were often laid on Blackbutt as the standard hardwood of the time. Half of them are still under carpet today.

For a holiday-let, Blackbutt is one of the easier surfaces to keep looking good between guest cycles. It hides sand and small marks better than lighter species like Tas Oak, does not scratch easily under guest wear, and refreshes well with a light re-coat every few years rather than a full strip-back.

The one thing worth flagging on every Blackbutt quote is tannin. The species carries high levels of water-soluble tannins, and a waterborne coating applied straight onto bare timber draws them to the surface as dark blotchy discolouration, uneven sheen and adhesion failure. A fast-drying shellac or alcohol-based isolation primer locks them into the grain and prevents it entirely. It is not repairable once it has happened — the floor has to be cut back and started again — which makes the primer the cheapest line item on the quote and the one most reliably missing from a cheaper one.

In the low-lying pockets where Blackbutt turns up under carpet — Seaford, the Karingal drainage basin, Capel Sound — the species is not the problem but the subfloor is. Blackbutt cups like any hardwood when the underside picks up moisture the heated top face is not, and it needs the same pin-type readings and the same 14 to 16 per cent threshold respected before anyone cuts it flat.