Spotted Gum vs Blackbutt: Which Timber Floor Suits Newcastle Homes?
After more than twenty years sanding floors across Newcastle and the Hunter Valley, I have worked on thousands of spotted gum and blackbutt floors. Both are outstanding Australian hardwoods, but they suit different situations. Here is what I have learned on the job.
Spotted Gum: The Character Timber
Spotted gum is one of the hardest domestically available timbers, rated at 11 on the Janka scale. It resists dents and scratches better than almost anything else you can put on a floor. The grain has a distinctive wavy figure and the colour ranges from pale brown through to deep chocolate, often in the same board.
In suburbs like Merewether and Hamilton, I see spotted gum in a lot of federation and interwar homes. It holds up well against beach sand tracked in from the coast, and it takes a Bona finish beautifully.
The downside? Spotted gum moves. It expands and contracts more than blackbutt in response to humidity changes. Newcastle's coastal moisture levels mean you need to allow for that movement during installation. Boards laid too tight will cup or buckle in summer.
Blackbutt: The Reliable All-Rounder
Blackbutt sits around 9.1 on the Janka scale. Not as hard as spotted gum, but still well above most imported timbers. The colour is more uniform -- pale golden brown with a straight, even grain. It suits modern builds and open-plan living areas where you want a clean, consistent look.
Blackbutt is more dimensionally stable than spotted gum. It handles Newcastle's humidity swings without as much fuss. I often recommend it for new builds in Charlestown and the Lake Macquarie area where the homes have large open rooms and concrete slabs.
It is also a BAL-29 rated bushfire timber, which matters if you are building anywhere near the bush fringe around Cessnock or Raymond Terrace.
Which Finish Works Best?
Both species respond well to water-based polyurethane. I use Bona Traffic HD on most jobs because it gives a hard, clear finish that does not yellow over time. On spotted gum, a satin finish brings out the natural figure without making the floor look like a bowling alley. Blackbutt looks excellent in either satin or matt.
If you want a darker look, spotted gum takes stain unevenly because of its interlocked grain. Blackbutt accepts stain more predictably. I always do a test patch first -- there is no point committing to a full floor stain based on a swatch card.
Cost Comparison
Supply prices shift, but spotted gum typically runs 10-15 percent more than blackbutt per square metre. The sanding cost is the same for both. Check my Newcastle pricing guide for current sanding rates.
My Recommendation
If you value character and do not mind a bit of natural movement, spotted gum is hard to beat. If you want consistency and stability with less risk, blackbutt is the safer choice. Both will last decades with proper care and maintenance.
Not sure which species is on your floor? Send me a photo through the contact page and I will identify it for you. I have been staring at timber grain long enough to pick most species from a photograph.
You can also visit the gallery to see finished examples of both species in Newcastle homes.