Removing a glued-down timber strip floor is a labour-intensive job, but it's absolutely achievable as a DIY project if you take your time and use the right approach. The key is working methodically to break the adhesive bond without gouging or cracking the subfloor beneath — whether that's a concrete slab or a timber substrate.
Understand What You're Working With
Before you start swinging a pry bar, identify your subfloor type. In New Zealand homes, glued timber strip floors are most commonly laid over:
- Concrete slabs — common in modern builds and post-1980s construction
- Plywood or particleboard sheeting — typical in older timber-framed homes
The adhesive used also matters. Older floors may have been laid with bitumen-based mastic (a black, tar-like adhesive), while more recent installations often use polyurethane or MS polymer adhesives. Bitumen adhesive is notoriously stubborn and can contain asbestos in floors laid before the mid-1980s — more on that below.
Safety First: Check for Asbestos
If your home was built before 1990 and you suspect the adhesive or any underlayment could contain asbestos, stop and get it tested before proceeding. Disturbing asbestos-containing materials is a serious health risk. Contact a licensed asbestos assessor or removalist, and check WorkSafe NZ for guidance on safe handling requirements. This is not a step to skip.
Also wear appropriate PPE throughout the job: safety glasses, heavy-duty gloves, knee pads, and a P2 dust mask at minimum.
Tools You'll Need
- Floor scraper (long-handled, with replaceable blades) — your most important tool
- Oscillating multi-tool with a scraper blade
- Pry bar and hammer
- Circular saw (to cut boards into manageable sections)
- Heat gun or floor adhesive remover (for stubborn glue residue)
- Belt sander or drum sander (for final subfloor cleanup, if needed)
- Stiff broom, vacuum, and rubbish bags
You can hire most of these tools from Bunnings or your local hire centre if you don't own them.
Step-by-Step Removal Process
1. Score and Section the Floor
Using a circular saw, set the blade depth to just the thickness of the timber boards (typically 18–19 mm for strip flooring) — do not cut into the subfloor. Cut the floor into strips or sections roughly 300–600 mm wide. This makes boards easier to lever up and reduces the risk of large pieces cracking the subfloor as they come away.
2. Start at a Wall or Doorway
Begin prying at a wall edge or doorway where you have a natural gap. Slide your pry bar under the first board and apply steady, even pressure. Avoid sharp, jerking movements — these are what crack concrete or tear up plywood.
3. Work Along the Grain
Timber strip floors are tongue-and-groove, so work along the length of the boards rather than across them. Once you free the first few boards, subsequent ones often come up more easily.
4. Use Heat or Solvent on Stubborn Adhesive
If boards refuse to budge, a heat gun applied to the surface for 20–30 seconds can soften polyurethane adhesives enough to allow removal. For bitumen mastic, purpose-made adhesive removers (available at Mitre 10 or PlaceMakers) can help dissolve residue. Always follow the manufacturer's instructions and ventilate the area well.
5. Clean the Subfloor
Once all boards are up, you'll be left with adhesive residue. Use your long-handled floor scraper to remove the bulk of it. For concrete slabs, a drum sander or angle grinder with a scarifying disc can be hired to grind off remaining adhesive — this is often necessary before laying a new floor. For plywood subfloors, be more conservative; aggressive sanding can thin the sheet and compromise its structural integrity.
6. Assess and Repair the Subfloor
Check the subfloor carefully for:
- Cracks or damage in concrete (fill with a suitable floor-levelling compound such as those from Ardex or Mapei)
- Delamination or soft spots in plywood (damaged sheets may need replacing)
- High spots or dips that will affect your new floor installation
A flat, sound subfloor is critical — BRANZ recommends subfloor flatness tolerances of no more than 3 mm under a 1.8 m straightedge for most flooring types.
Protecting the Subfloor: Key Tips
| Risk | How to Avoid It |
|---|---|
| Gouging concrete | Keep scraper blade at a low angle (15–20°) |
| Tearing up plywood | Use a wide pry bar to spread load evenly |
| Cutting too deep with saw | Set blade depth carefully before cutting |
| Cracking slab with leverage | Work in small sections; don't use excessive force |
When to Call a Professional
Consider hiring a qualified flooring installer or floor sanding professional if:
- Asbestos is suspected — this is non-negotiable; licensed removal is required
- The subfloor is in poor condition and needs significant repair or levelling
- You're working with a large area (over 30–40 m²) where fatigue and technique errors become costly
- You're unsure of the adhesive type or subfloor construction
- You want to salvage the timber boards for reuse — a professional can often remove boards with less damage
A skilled flooring installer will also be able to assess whether your subfloor meets the requirements for your intended new floor covering. You can find qualified local flooring professionals on tradedirectory.co.nz.
