If your timber floors are looking a little tired, you may have been quoted for either a screen buff and recoat or a full sand and finish. These are very different processes with different costs, results, and disruption levels — and choosing the wrong one can either waste money or leave you disappointed with the outcome.
What Is Screen Buffing?
Screen buffing (also called a buff and recoat, or abrade and recoat) is a light surface preparation process. A floor buffer fitted with a mesh abrasive screen — typically 120 to 180 grit — is used to lightly scuff the existing coating without cutting down into the timber itself. The goal is simply to degloss the surface so a fresh coat of finish will bond properly.
After screening, the floor is vacuumed and tacked clean, then one or two new coats of polyurethane, oil, or another finish are applied on top of the existing coating system.
When screen buffing works well:
- The existing finish is still largely intact with no peeling, flaking, or bare patches
- The floor has minor surface scratches, scuff marks, or dullness
- The timber itself is in good condition — no deep gouges, staining, or cupping
- You want a cost-effective refresh with minimal downtime (often just one to two days)
- The floor has been previously coated with a compatible finish
What Is a Full Sand Job?
A full sand (or full sand and finish) involves using a large drum sander or belt sander to mechanically remove the existing coating and a thin layer of the timber surface itself. This is a much more aggressive process that typically goes through several grit stages — starting coarse (around 24–40 grit) and finishing fine (80–120 grit) — before edging, hand-scraping corners, and applying a completely fresh coating system from scratch.
A full sand can remove deep scratches, stains, minor cupping, and old failing finishes, and it allows you to change the colour of your floor with a stain if desired.
When a full sand is necessary:
- The existing finish is peeling, flaking, or has bare patches
- There are deep scratches, gouges, or ingrained staining
- The floor has never been sanded before (e.g., original rimu or pine boards)
- You want to change the colour or switch to a different finish type
- The floor has been screen buffed multiple times and the coating is too thick
- There is minor cupping or unevenness that needs to be levelled
Key Differences at a Glance
| Feature | Screen Buff & Recoat | Full Sand & Finish |
|---|---|---|
| Timber removed | None | Yes — thin layer |
| Existing finish removed | No — abraded only | Yes — fully stripped |
| Fixes deep scratches | No | Yes |
| Colour change possible | No | Yes |
| Typical downtime | 1–2 days | 3–5+ days |
| Relative cost | Lower | Higher |
| Dust generated | Minimal | Significant |
| Number of times possible | Limited by coating thickness | Limited by timber thickness |
How Many Times Can You Sand a Floor?
This is an important consideration for NZ homeowners. Most solid timber floors (such as rimu, matai, kauri, or heart pine) can be sanded multiple times over their lifetime — but each full sand removes material, so there is a finite number of sands possible depending on the board thickness and how much timber sits above the tongue and groove. A qualified floor sander can assess this with a moisture meter and by checking board thickness.
Engineered timber floors have a much thinner wear layer (sometimes only 2–4 mm) and may only tolerate one or two light sands, if any. Always check with the manufacturer or a professional before sanding engineered boards.
Compatibility of Finishes Matters
One thing many homeowners overlook is finish compatibility. If your floor was previously coated with a hard-wax oil and you try to screen buff and apply a water-based polyurethane on top, the new coat may not bond correctly and could peel. A professional floor sander will test the existing finish and advise whether a screen buff is safe or whether a full sand is the only reliable option. BRANZ provides useful guidance on building materials and finishes for NZ conditions.
DIY Considerations
Hire equipment for both processes is available from stores like Bunnings and Mitre 10, but floor sanding — particularly a full sand — carries real risk for the inexperienced. Drum sanders are aggressive machines; a moment's hesitation can leave visible dips or chatter marks that are difficult to fix. Dust is also a significant health and fire hazard. WorkSafe NZ recommends appropriate respiratory protection and dust management when sanding timber.
Screen buffing with a rotary buffer is more forgiving and is sometimes tackled by confident DIYers, but achieving a streak-free, even finish still takes practice.
When to Call a Professional
For a full sand job, calling a qualified floor sanding professional is strongly recommended. They have the right equipment, dust containment systems, and experience to assess your floor's condition, choose the correct grit sequence, and apply a durable finish. A professional can also advise on the best coating for your lifestyle — whether that's a water-based polyurethane, a solvent-based finish, or a penetrating oil — and ensure the result lasts. You can find qualified floor sanders in your area on tradedirectory.co.nz.
For screen buffing, a professional is still the safest choice if you're unsure about finish compatibility or the overall condition of your floor.
