How to lay engineered timber flooring as a floating floor

Floating engineered timber: the job at a glance

1. Read the installation instructions: floating or glued, underlay, gap and stagger.
2. Leave the unopened packs to acclimatise in the room.
3. Check that the subfloor is dry, level and firm.
4. Lay a moisture barrier and underlay as the instructions say.
5. Plan the rows: direction, first and last row widths, and the stagger.
6. Lay the first row with spacers for the expansion gap.
7. Stagger the end joints and start rows with offcuts where the rules allow.
8. Cut the last row to width, then fit the skirting or scotia.

Before you start

Remove carpet and other soft floor coverings. On a concrete slab, grind down high spots and fill dips; on particleboard or timber floorboards, screw down anything loose or creaking. Check flatness with a 2 m straightedge; the instructions say how much unevenness is allowed. Timber reacts to moisture more than laminate does, so check the subfloor moisture as the instructions describe, especially on a new concrete slab.

Acclimatising

Bring the unopened packs into the room and leave them flat. Many manufacturers state 48 hours at normal room temperature; check the time your instructions give. Open the packs only when you start laying.

Moisture barrier and underlay

On a concrete slab, lay the moisture barrier your instructions ask for, often polythene sheet with overlapped, taped joins. Over particleboard or plywood on a suspended timber floor, follow the instructions for timber subfloors, which may ask for no barrier at all. On top goes the underlay your timber manufacturer names for a floating floor. In an apartment or unit, check the body corporate's rules on acoustic underlay before you choose one.

Suspended timber floors and slabs

Many New Zealand houses have a suspended timber floor: particleboard or plywood sheets on joists, over a ventilated space underneath. A floating floor can go over sheet flooring that is dry, flat and firmly fixed. Screw down any sheet that moves or squeaks, and sand or fill the joints so they are level.

Check that the space under the floor is ventilated and dry, because damp underneath shows up as movement in the timber above. On a newer house built on a concrete slab, check that the slab is dry enough before you start, as your instructions describe: a new slab takes a long time to dry.

Plan the rows before you cut

Long boards make mistakes expensive: a wrong cut on a 1900 mm board wastes far more than on a short laminate board. Plan three things together before the first cut.

Example: A 4.8 × 3.4 m room with 1900 × 190 mm boards (an example size) laid lengthways, with a 10 mm expansion gap at each wall. The floor is 3380 mm wide between the gaps. The plan keeps a full 190 mm first row, and the last row is 150 mm wide. The plan has 18 rows and uses 46 boards with 20 cuts, and the wastage it measures is 2.7%.

• Direction. Usually towards the light from the main window, or along the room. See which way to lay hybrid flooring; the same reasoning applies to engineered timber.
• First and last rows. Work out the last row before you lay the first, so neither edge row ends up as a sliver. Read how to avoid a narrow last row.
• Stagger and end pieces. Long engineered boards often need a larger offset than laminate, so take the figure from your product's manual. Enter your product's minimum stagger and shortest end piece, and the plan checks every row.

Laying engineered timber step by step

The first row and the expansion gap

Start along a long, straight wall with spacers between the boards and the wall. Use the expansion gap your product's instructions give: timber floors and large rooms often need more than laminate, and many floors need an expansion joint in doorways. Check the first row with a string line: every row after it follows it.

Staggered end joints and offcuts

Start the next row with the offcut from the previous one if it is long enough and keeps the stagger. If it is too short for the next row, keep it: a later row may use it. The cutting plan shows which offcut goes where.

The last row

Measure the gap to the wall at both ends of the row, take off the expansion gap and cut the board to width. Use a pull bar where there is no room for a tapping block.

Door frames and skirting

Undercut the door frames so the boards slide underneath. Fix the skirting or scotia to the wall, not to the floor, so the floating floor can move.

Random-length boards: what the plan can't do

Some engineered timber comes in packs of mixed lengths. PlankBuddy plans with one board length, so it cannot give an exact plan for random-length packs. You can still use it to check the row widths, the first and last rows and the expansion gap, which depend only on the board width.

PlankBuddy lays straight rows only. Herringbone and other block patterns need a different kind of plan.

Questions about laying engineered timber flooring

See the laying rules that shape every row, or how to lay hybrid flooring step by step.