Floating Timber Floor Installation (Click/Clack)

The fitter starts by checking the subfloor and preparing the room. The boards should rest in the room where they will be laid for a few days, usually at least 48 hours, so the wood can adjust to the temperature and humidity. They normally stay in their unopened packs during this time, but the manufacturer's instructions have the final say.

Next the underlay goes down and the fitter decides which way the boards will run. Why do boards usually run in the direction of the light from the window? The joints show less, and the room looks longer. The first row goes along a straight wall, with spacers between the boards and the wall to keep the expansion gap. This gap is usually around 10 mm, and the flooring manufacturer gives the exact figure.

To join the boards, the fitter angles each new board into the long-edge joint and lowers it until it clicks into place. Depending on the locking system, the short ends either drop in from above or are tapped together gently through an offcut. The end joints in neighbouring rows are staggered, usually by at least 30 cm. This makes the floor more stable and avoids a regular "ladder" pattern. The last row is cut to width, the spacers come out, and finally the skirting boards and threshold strips go on.

A click joint is precise, so it needs a subfloor that is flat, firm and dry. Manufacturers usually allow a deviation of only a few millimetres over a length of one to two metres. Larger dips and bumps are ground down or filled with self-levelling compound. The subfloor is primed before the compound goes on so that it bonds well.

Old carpet, vinyl or linoleum usually comes up before a timber floor goes down, along with any leftover adhesive. A soft covering under a floating floor makes it spring underfoot and puts strain on the joints.

On concrete or another mineral subfloor you need a vapour barrier. This is usually polyethylene sheeting with overlapping, taped joints, or an underlay that already has a barrier built in. A new screed must be dry enough before the floor goes down. The fitter measures the moisture level, and the flooring manufacturer gives the limits for each type of screed.

Underlays differ mainly in how well they reduce footfall noise and how much they even out small irregularities:

• Foam underlays are common, light and suitable for most dry rooms.
• Cork underlays dampen noise well, but on their own they do not protect against moisture.
• Combination underlays provide sound insulation and a vapour barrier in one roll.

With underfloor heating, use a floor and an underlay that the manufacturer clearly approves for it. An underlay that is too thick holds back the heat.

The simplest case is a rectangular room with a flat subfloor, no pipes and few doors. These things add time and effort:

• an uneven or damp subfloor that has to be repaired and left to dry first
• an irregular layout with alcoves, pillars or angled walls
• radiator pipes, where boards have to be drilled and the holes covered with pipe roses
• many doorways, where door frames need undercutting and threshold strips need fitting
• stairs and transitions to tiles at a different height
• large areas that need an expansion profile according to the manufacturer
• laying a floor in a lived-in home, where furniture has to be moved around

In a flat, ask the building management or owners' association beforehand whether there are rules on footfall noise or on noisy work. Replacing a floor covering is routine work. If you plan to alter the floor or ceiling structure itself, check with the local building authority first.

• No expansion gap. Wood moves. If it presses against a wall, door frame or pipe, the floor lifts and bulges. In practice a heavy wardrobe or a skirting board screwed down too tightly often closes the gap.
• A floating floor that is pinned down. Kitchen units or fitted wardrobes standing on the boards weigh the floor down and stop it moving. This kind of furniture is installed before the floor, or the floor stops short of it with a gap.
• An uneven subfloor. Boards over a dip flex, the joints come under strain, and squeaks and gaps appear.
• Joints not fully closed. A joint that has not fully engaged will open up over time. Tapping directly on the edge of a board damages the locking profile.
• No vapour barrier on concrete. Moisture from the subfloor reaches the wood and the boards start to cup.
• Timber in wet rooms. A floating timber floor is not normally laid in bathrooms or saunas.

A capable amateur can lay a click floor in a dry, regularly shaped room. You will need a saw, a tape measure, a square, spacers, a rubber mallet and a tapping block. Always read the manufacturer's instructions, because locking systems differ.

1. Leave the packs of boards to acclimatise in the room as the manufacturer instructs.
2. Remove the old soft floor covering, then clean and vacuum the subfloor.
3. Check flatness with a long straightedge and level out any irregularities.
4. On concrete, lay a vapour barrier with overlaps and tape the joints.
5. Roll out the underlay with the edges butted together, not overlapping.
6. Measure the width of the room and plan the rows so the last one is not too narrow.
7. Undercut the door frames to the height of a board plus underlay.
8. Lay the first row with the tongue facing the wall and insert spacers for the expansion gap.
9. Join the following rows and stagger the end joints as the manufacturer recommends.
10. At pipes, drill holes larger than the pipe and glue the cut-out piece back in place.
11. Cut the last row to width while keeping the gap at the wall.
12. Remove the spacers and fix the skirting boards to the wall, not to the floor.
13. Fit threshold strips at doorways and where the floor meets another covering.

• Joints are closed along their full length and the boards do not lift at the joints
• The floor does not flex or squeak when you walk on it
• An expansion gap remains along all walls, door frames and pipes
• Skirting boards are fixed to the wall and do not press down on the floor
• Threshold strips sit firmly and do not create a trip hazard
• End joints are staggered and do not form a regular pattern
• The last row is not noticeably narrower than the others
• The surface has no scratches, chipped edges or marks from tapping
• Doors open freely and do not rub on the floor
• You have received the spare boards and the manufacturer's care instructions