Jarrah Flooring

Sanding and finishing guide for jarrah (Eucalyptus marginata) -- a rich red Australian hardwood with moderate tannin and a loyal following among homeowners and contractors.

Species characteristics

• Janka hardness: 8.5 kN -- moderately hard. Easier to sand than ironbark or spotted gum, comparable to blackbutt.
• Grain: Straight to slightly interlocked. Generally sands well without the tearing issues seen on spotted gum.
• Colour: Rich red-brown to deep burgundy. Jarrah's colour is its defining feature. Freshly sanded jarrah is lighter and pinker; it darkens and deepens with age and UV exposure.
• Tannin level: Moderate. Lower risk than blackbutt or ironbark, but tannin bleed can occur on fresher boards or boards with high moisture content. Worth priming with Prime Intense as a precaution on water-based systems.
• Common issues: Colour variation between boards (heartwood vs sapwood), occasional gum veins, and sensitivity to finish choice -- water-based keeps the natural red, solvent adds amber-gold warmth.

Recommended grit sequence

• Belt sander: P40 → P60 → P80 → P100 (SIA belts). Start at P24 only if the floor is in very rough condition (heavy old finish, deep scratches, or significant cupping).
• Edger: P40 → P60 → P80 → P100.
• Buffer/screen: P120 screen to blend belt and edger zones and remove any fine raised grain.

Jarrah sands predictably. The straight grain and moderate hardness mean belts last reasonably well and the surface comes up smooth at each grit. Use the Grit Sequence Picker for a recommendation tuned to the floor's specific condition.

Recommended primer

Bona Prime Intense is recommended for jarrah under water-based topcoats. While jarrah's tannin risk is lower than blackbutt, Prime Intense provides insurance against bleed and brings out the depth of jarrah's red tones. On a species where colour is the main selling point, the colour enhancement alone justifies the primer choice.

If the jarrah floor is confirmed to be very old, dry, and low-tannin (e.g. recycled jarrah that has been exposed to air for decades), Classic UX can be considered. However, Prime Intense remains the safer default for any jarrah floor where there is uncertainty about tannin content.

Finish choice: water-based vs solvent on jarrah

This is the key decision on jarrah because the finish dramatically affects the final colour:

• Water-based (Bona): Preserves the natural red-pink tone of freshly sanded jarrah. Over time, jarrah will still darken naturally with UV, but the finish itself adds no amber. This is the modern approach and suits clients who want the red without the gold.
• Solvent (Handley Urethane): Adds a warm amber-gold tone on top of the natural red, giving jarrah a deeper, richer appearance. This is the traditional finish that many jarrah owners expect. Solvent also avoids the tannin bleed risk entirely.

Show the client a test patch of each before committing to the full floor. On jarrah, the difference between water-based and solvent is more visible than on most other species.

Recommended topcoats

• Bona Traffic HD: Commercial-grade protection for high-traffic jarrah floors. Preserves the natural red tone.
• Bona Wave 2K: Heavy residential 2K. Good durability for open-plan living areas.
• Bona Mega: Standard residential. Reliable and easy to apply.
• Bona Traffic GO: Fast-cure 2K for tight timelines.
• Handley Urethane: Traditional solvent finish for the warm amber look. Available in gloss, satin, and matt.

Common mistakes on jarrah

• Not discussing finish type with the client. Jarrah changes colour dramatically depending on whether the finish is water-based or solvent. A client expecting the rich amber glow of a traditional solvent finish will be disappointed by a clear water-based result (and vice versa). Always show a test patch.
• Mixing heartwood and sapwood without warning the client. Jarrah sapwood is pale cream. Heartwood is deep red. If the floor contains both (common in older installations), the contrast will be stark after sanding. This is a characteristic of the timber, not a sanding fault, but clients need to know in advance.
• Skipping primer on water-based systems. Jarrah's moderate tannin can still cause bleed on fresher boards. Prime Intense is cheap insurance on a species where a callback means re-sanding a beautiful red floor.
• Over-sanding gum veins. Jarrah often has gum veins (dark resin pockets). These are a natural feature. Aggressive sanding over gum veins can dislodge the resin and leave voids. Sand gently over gum veins and fill any voids with a colour-matched filler before priming.

FAQs: jarrah flooring

Can jarrah be stained?

Jarrah can be stained, but the natural red colour is strong. Dark stains (espresso, walnut) work better than light stains, which struggle to overpower the base colour. Bona DriFast Stain in darker tones produces a consistent result. Test a small area first.

Does jarrah need Prime Intense or can Classic UX be used?

Prime Intense is recommended as the default for jarrah under water-based topcoats. Classic UX is acceptable only on confirmed low-tannin, very old recycled jarrah. When in doubt, use Prime Intense.

Is jarrah still available for new installations?

Jarrah supply has tightened due to logging restrictions in Western Australia. Most jarrah floor work today is restoration of existing floors or installation of recycled jarrah. The timber is durable enough to sand and refinish multiple times over its lifetime.

Tools

• Grit Sequence Picker -- pre-set for jarrah
• Primer Picker -- primer recommendation for jarrah
• Coverage Calculator -- litres of primer and topcoat for the job