General rule

The assessment criteria are indicative and are used in the assessment of flaws and failures in connection with the delivery of floor work.

Cosmetic defects must be visible and assessed by an independent assessment based on the criteria normally used for a handover business in connection with laying wooden floors, see TRÆfakta 03 Wood Floors - Complaints.

Flaws that can only be seen at a particular light effect or viewing angle, or which are only seen after they are pointed out, will not normally be considered a defect.

Failure is physical faults and defects on the floor which degrade the function to an extent so that current industry tolerances for wooden floors are exceeded.

For renovation works where boards or rods are replaced, color differences between old and new surfaces must be tolerated, see TRÆfakta 06 Wooden floors - Assessment of color differences.

If beauty defects and failures are considered significant, they must be remedied by the floor layman / supplier, see the industry guidelines TRÆfakta 03 Wooden floors - Complaints.


The prerequisite for assessing failure and cosmetic errors is that the indoor climate is mainly kept within the normal limits for the use of wood floors, see the manuals TRÆ 63 and 64 Wood floors.

Moisture and temperature

The humidity conditions are crucial for the size of certain faults. For tolerances and faults related to moisture conditions, the humidity and the moisture of the wood must be in equilibrium, and the indoor climate must be within the following tolerances:

  • Room temperature: 18-25ºC
  • Humidity (RF): 30-65%

In addition, for wooden floors with underfloor heating, the highest temperature on the wooden floor surface does not exceed 27 ºC at any time.

Visual assessment

For assessment of deficiencies, reference is made to the guidelines for visual assessment in TRÆ-facts 03 Wooden floors - Complaints.


Deficiencies in delivered floor materials should, as far as possible, be ascertained by floor layers by sample checks of deliveries before the boards are laid, eg. moisture content, width deviation, right angle, landing deviation, washing board, side curvature and color deviations so that the defects do not lead to floor defects.

Detailed rules (indicative)

Lack of materials and laying



Cracks or edge damage (eg from hammer blows)

Replacement of board / rod. Minor errors are spared / repaired, if possible.

Point injuries, pressure marks, scratches and finish damage

The reason for the damage must be examined, including the necessary cover. Small and few faults are rectified. Larger damaged floor areas are abraded and re-treated if possible. Alternatively, the floor should be replaced.

Landing deviations> 0.2-0.3 mm (see WOOD 63)

Replacement of board / rod. For minor defects on oiled floors, repair may be possible. by grinding and refining.

Knot holes, cams

Replacement of board / rod at larger number per unit. floor surface. Minor number of plugs or spares and surface finishes.

Width deviation Parquet boards> ± 0.2 mm Parquet bars> ± 0.5 mm

For width deviations of parquet board / rod width greater than 0.2 and 0.5 mm respectively: Replacement of board / rod. For solid floorboards, please refer to the supplier's product instructions.

Side curvature> 0.1% of the floor length for solid floors,> 0.05% for slat floors

Replacement of board / rod.

Joints> 0.6% of the board width (measured at 30-65% RH)

The reason for the joint formation must be investigated. The remedy depends on the result.

Deviation from rectangular unit> 0.2% of the width of the board

In individual cases, the putty is remedied. In the event of continuous faults, boards / rods are replaced.

Insufficient expansion options (usually at least 10 mm along walls)

Freshening and establishing dilatation joints.

Lack of flatness Deviation> ± 2 mm / 2 m retracted and ± 0.6 mm / 0.25 m retracted

Stroke floors: Partial or complete pick-up of floors and alignment of blocks. Glued floors: Partial picking of rods, alignment of lukewarm and re-gluing of new rods. Floating floors: Partial or complete alignment of the substrate and reloading of the floor.

Resilience> 2 mm / 2 m retracted

Stroke floors: The cause of the failure must be investigated. Checks and stiffness properties of the floorboards are controlled by static load 0.75 kN. When using audio chips, the resilience may be greater. Remedy depends on the result.

Deviation from horizontal maximum = 10 mm / 6 m

Reason for deviation must be investigated. Remedy depends on the result.

Loose bars in slat floors, eg. due to glue failure

Replacing the rods. With extensive failure - replacement of the floor.

Joint between floor and base strips> 4 mm

Footsteps are remounted or sand strips are attached.

Dark or light boards / rods

Factory-produced floors: In case of significant deviation from the supplier's sorting criteria: Replacement of board / rod. Floors made on site: Color differences resulting from surface treatment after laying and sanding must be tolerated.

color Differences

Not usually remedied if they are due to normal differences in the wood material or different supplies (bats)

Color changes in the wood, e.g. due to light impact

Not remedied, since color differences cannot always be detected by laying untreated or newly treated floor surfaces, since color changes often occur over time. due to light effect, e.g. red and brown coloring of pine boards, or due to surface treatment, see TRÆfakta 06: Assessment of color differences.

Discoloration, e.g. mildew spots under lacquer surfaces

Replacement of boards / rods.

Brands on lacquer and oil-treated floors

Replacement of painted boards / rods. Partial repair and grinding of oiled floors and new treatment of the entire floor surface.

Washing board Solid boards> 0.3% Slat floors> 0.15%

The reason for the curvature must be examined, see WOOD 63. Remedy depends on the result.

Murmurs / squeaks

The cause of the mishaps must be investigated, see TRÆfakta 02. Remedy depends on the result.

Mute sounds / creaking sounds when reloading lamella floors

Not remedied, as not all lamella floors can be taken up and passed through without the risk of noise from click assemblies. Supplier instructions must be followed.

Non-professional execution of minor, profiling, etc.

Natural wood moldings are replaced. In case of minor errors on painted lists, etc. moisten and repaint the moldings

Press marks, e.g. from hammer, on lists etc.

Natural wood moldings are replaced. In case of minor errors on painted lists, etc. moisten and repaint the moldings.


Detailed rules (indicative)

Lack of factory surface treatment



Lack of adhesion in the paint or oil layer

1: Grinding and re-painting / remediation, if possible.

2: At oil-treated floors, the surface is spot-repaired.

3: For lacquered and UV-hardened oil-treated floors, where remediation according to 1 and 2 is not possible, replace the boards.

The surface finish shells

Grinding and re-painting / remediation, if possible. Alternatively: Replacing boards / rods.

Permanent marks, poor absorption and color change in the oil treatment

Dry sanding with a hard round, as well as oiling and polishing. Alternatively: Re-grinding and re-treatment.

Uneven gloss in paintwork

Grinding and re-painting / remediation, if possible. Alternatively: Replacing boards / rods.

Insufficient or non-uniform pigmentation

Abrasive and new treatment.

Discoloration, mold, particles, etc. under topcoat

Replacement of boards.


Lack of surface treatment on site



Uneven lacquering, lasering, pickling or nibbling

Intermediate grinding and lacquering / treatment of the entire floor, or grinding and reworking.

Slip in paint or oil surfaces

Lacquered floors: sanding and painting. Oiled floors: Partial grinding and oiling.


Grinding and painting

Brands, poor suction and color change due to inadequate abrasion

Grinding and oiling.

Excess oil forms a glossy surface

Dry sanding with hard pad and oiling and polishing, or grinding and oiling the entire floor.

Insufficient paint or oil

Lacquered floors: Medium sanding and painting of the entire floor. Oiled floors: Clean the entire floor.

Insufficient or flamed pigmentation on lye-treated boards

Abrasive and new treatment.

Insufficient lye treatment

Abrasive and new treatment.

Some smaller particles, dirt and abrasive dust

Judged by the general rule, see page 2. Some smaller particles are sanded / scraped off and the surface treated as possible. In the case of defects to a greater extent: sanding and new treatment.


Lack of floor grinding



Insufficient grinding, cutting or grinding marks

Re-grinding and new treatment.

Local insufficient sanding

Re-grinding and new treatment.

Grinding Rande

Re-grinding and new treatment.

Ring by edge grinding

Re-grinding and new treatment.

Lack of grinding or scraping in corners

Lacquered floors: sanding and painting. Oiled floors: Partial grinding / sharpening and oiling