How to install parquet flooring
What has to be right before the first board goes down – subfloor moisture, flatness, room climate – and then how to float or glue it, straight or in herringbone. With the limits from manufacturer instructions and German trade rules.
This guide is for anyone who wants to float a click-jointed engineered parquet floor themselves, and for anyone hiring a floor layer who wants to know what should be checked. Most parquet failures are caused before laying, not during it: a screed that is still too damp, air that is too dry, a missing wall gap. So check the numbers below first. They come from parquet and adhesive manufacturers' instructions; in the end, the instructions for your product always win.
Check these numbers before you start
Residual moisture, measured by the calcium carbide method and recorded: cement screed at most 2.0 %, over underfloor heating at most 1.8 %; calcium sulfate screed at most 0.5 %, over underfloor heating at most 0.3 %. Fast-drying and flowing screeds: the screed manufacturer's value. Some Swiss rules allow only 1.5 % for heated cement screed.
Timber subfloor: at most 12 % wood moisture; wood-based panels at most 11 %. No polyethylene film on timber.
Flatness: level any deviation of more than 2 mm over 1 m (check with a 1 m straightedge or a level).
Climate: air at least 18 °C, subfloor at least 15 °C, relative humidity 40–60 %, kept steady from 2 days before until about 5 days after laying.
Underfloor heating: the screed has been heated up following a written heat-up protocol and then moisture-tested. The thermal resistance of parquet plus adhesive or underlayment is at most 0.15 m²K/W.
The subfloor is solid, free of cracks and clean, with no old carpet or other textile covering left on it.
In Germany, parquet work is contracted under DIN 18356, and flatness tolerances are set by DIN 18202.
Installing parquet in 9 steps
Acclimate the boards
Store the packs unopened and lying flat in the room where they will be laid, on 3–4 battens and about 1 m from the walls so air can circulate: at least 24 hours, 48 hours for some manufacturers, at around 20 °C and 50–60 % humidity. Open them only just before laying. Check every board in good light – boards with visible defects are not replaced once they are down.
Measure and prepare the subfloor
Have the residual moisture measured by the calcium carbide method (limits above) and record it. Check flatness with a straightedge, fill dips of more than 2 mm per meter and respect the drying time of the leveling compound. Vacuum and have cracks repaired. With underfloor heating: is the heat-up protocol finished and signed?
Measure the room and plan the first row
Straight boards usually run toward the main light, and lengthwise in a hallway. Measure the room across the board direction and work out how wide the last row will be: if it comes out very narrow, rip the first row narrower so both edge rows are similar. Walls are rarely straight – scribe the first row to the wall, not the other way around.
Floating: film and underlayment
On a mineral screed, first lay polyethylene film at least 0.2 mm thick as a vapor retarder: overlap the sheets by 200 mm, tape them tight and turn the film up 20 mm at the walls. Butt the underlayment on top without overlaps – manufacturers often limit its thickness to 3 mm. Trim the film at baseboard height only after laying.
Glue-down: adhesive and trowel
Use a parquet adhesive (elastic silane-modified or polyurethane) that your parquet manufacturer approves, and follow its data sheet. Typical: trowel notch B11 to B15, about 1.0–1.2 kg/m² for short engineered formats and 1.4–1.5 kg/m² for plank formats and solid strip. Spread only what you can cover within the open time (often around 30 minutes). Slide the boards in, press them down and wipe off adhesive at once.
First rows with the wall gap
Set wedges for a gap of 10–15 mm to every wall, door frame, heating pipe and fixed part, depending on the manufacturer. With click parquet, the tongue side faces the wall. Align the first rows carefully; any error here runs through the whole room.
Lay the field
Mix boards from several packs so color and grain even out. Offset the end joints in neighboring rows by at least 30–40 cm (the manufacturer's figure), and keep cut pieces at row ends at least 20 cm long. Start the next row with the offcut when it is long enough. For heating pipes, drill a hole of pipe diameter plus 20–30 mm, cut the board through the hole and glue the piece back in.
Herringbone: work from the center line
Herringbone does not start at a wall. Find the center line between opposite walls and shift it parallel by the distance given in the manufacturer's instructions – for one product it is 5.7 cm for a single braid and 11.5 cm for a double braid; this line sits over the tips of the braid. Glue a first braid of four blocks in the middle of the room, let it cure, then work outward. Edge pieces are cut at 45°.
Joints, baseboards, transitions, waiting times
Put movement joints in doorways and on long runs (from 8 m with some manufacturers, from 12 m along the boards with others) and cover them with profiles. Remove the wedges and fix baseboards to the wall, never through the parquet. Load glued parquet only after the curing time on the adhesive data sheet (for example about 12–24 hours) and sand no sooner than 24 hours. Put felt pads on furniture straight away. Over underfloor heating, raise the flow temperature slowly afterwards; one manufacturer states at most 5 °C per day.
Float or glue?
| Situation | Method | Why |
|---|---|---|
| Click engineered parquet, ordinary living room, screed without heating | Float | Fast, no curing time, can be taken up later. A little louder underfoot. |
| Engineered parquet over underfloor heating | Glue recommended | Better heat transfer; manufacturers prefer gluing to floating. Float only if the manufacturer approves it. |
| Solid parquet, strip parquet, solid boards | Glue | Solid wood swells and shrinks more and needs a shear-proof bond to the subfloor. |
| Tongue-and-groove herringbone | Glue | These blocks are usually approved for glue-down only. |
| Heavy fixtures on the floor (kitchen, stove, aquarium) | Glue, or install the fixtures first | A floating floor must never be pinned down. |
Tools and materials
| Item | Quantity |
|---|---|
| Parquet | Floor area plus cut waste – count the waste for your room and pattern instead of assuming a flat rate; keep one spare pack for later repairs |
| Polyethylene film, 0.2 mm (floating on screed) | Floor area plus 200 mm overlap at each seam and 20 mm turned up at the walls |
| Underlayment (floating) | Floor area, butted; thickness as the parquet manufacturer specifies, often 3 mm at most |
| Parquet adhesive (glue-down) | About 1.0–1.5 kg/m² depending on format and notch (B11–B15) |
| Notched trowel with the right notch | One, plus a spare for large floors |
| Spacer wedges | Enough for a 10–15 mm gap along every wall |
| Tools | Fine-tooth saw, jigsaw, folding rule, square, pencil, drill bits for pipe holes, hammer, tapping block, pull bar for the last row, 1 m straightedge |
| Wood glue | For pieces cut around heating pipes |
| Baseboards and transition profiles | Room perimeter minus doors; one profile per doorway |
The most common mistakes
Laid without a recorded moisture measurement
How to spot it: Boards cup across their width, the adhesive lets go, joints open after the first winter.
Fix: Have it measured, record the value and keep to the limit for the screed type and heating. Heat up a heated screed following the protocol first.
Wall gap too small or blocked
How to spot it: The floor lifts in the middle of the room, creaks, and boards push up at door frames and pipes.
Fix: Leave 10–15 mm everywhere, including door frames, pipes and stairs. Never stand a kitchen, stove or built-in cabinet on a floating floor.
Air too dry or climate swinging
How to spot it: Wide gaps between the boards in winter, cupping in summer.
Fix: Keep 40–60 % relative humidity and humidify if needed; heat steadily before and after laying.
End joints too close or offcuts too short
How to spot it: A staircase pattern, short wobbly pieces at the edge, broken click joints.
Fix: Offset end joints by at least 30–40 cm and keep cut pieces at least 20 cm long.
Too little adhesive or left open too long
How to spot it: A hollow sound when tapped, boards that spring.
Fix: Use the notch from the adhesive data sheet, spread only what you can cover within the open time, slide the boards in and press them down.
When a professional is the better choice
Manufacturers want the screed moisture measured by a professional and recorded before parquet goes down. Beyond that, some jobs are trade work, because adhesive, primer, heat-up protocol and sanding all have to match.
- Solid parquet and glued herringbone
- Any glue-down over underfloor heating
- Sanding and sealing raw parquet, which needs a floor sanding machine and practice
- A subfloor that springs, is cracked or needs more than a few millimeters of leveling
Frequently asked questions
- How dry does the screed have to be for parquet?
- Measured by the calcium carbide method: cement screed at most 2.0 % (1.8 % over underfloor heating), calcium sulfate screed at most 0.5 % (0.3 % over underfloor heating). For fast-drying and flowing screeds, the screed manufacturer's value applies. The age of the screed alone tells you nothing – only the measurement counts.
- How long should parquet acclimate before laying?
- Manufacturers state at least 24 to 48 hours, with the packs unopened and flat, at an air temperature of at least 18 °C (around 20 °C is ideal) and 40–60 % relative humidity. Keep the climate steady for about 5 days after laying as well.
- How big should the gap to the wall be?
- 10–15 mm to all walls and fixed parts, depending on the manufacturer. You also need movement joints in doorways and on long runs – from 8 m in some instructions, from 12 m along the boards in others.
- Can parquet go over underfloor heating?
- Yes, if the product is approved for it. The thermal resistance of parquet plus adhesive or underlayment should not exceed 0.15 m²K/W, and the surface temperature limit is 24 to 29 °C depending on the manufacturer. Gluing is preferred to floating, and some manufacturers exclude electric underfloor heating.
- How much waste does herringbone parquet need?
- Clearly more than a straight lay, because every edge block is cut at 45°. The exact amount depends on the room shape, the block length and where the center line falls – counting beats any rule of thumb. Add one spare pack as well.
Know the board count before you shop
The planner cannot measure moisture, but it does the arithmetic: draw your room, pick the board size and pattern, and it places every board at real size, shows how wide the edge rows come out and counts boards and cut pieces.
Start planning