Parquet floors, whether in traditional herringbone block format or in more contemporary plank herringbone or chevron layouts, present specific challenges in floor finishing. The alternating grain directions of the blocks mean that sanding and varnish application need to be approached differently from straight-run plank floors. Getting this right produces a floor that looks even and professional; getting it wrong produces a floor with visible machine marks or uneven sheen.
Sanding Parquet: The Challenge of Grain Direction
In a standard herringbone parquet layout, adjacent blocks are laid at 90 degrees to each other. This means that sanding along the grain of one row of blocks produces cross-grain sanding on the adjacent row. True with-grain sanding in both directions simultaneously is impossible on a herringbone pattern.
The standard approach for sanding herringbone parquet is to sand diagonally, at 45 degrees to both block directions. This produces a 45-degree angle sanding direction on every block, which, while not ideal for any individual block, is equally consistent across the entire floor. Starting with 40-grit diagonally and progressing to 60-grit and 80-grit at the same angle, then finishing with an 80-grit or 100-grit orbital or vibrating sander across the whole floor, produces a good surface ready for varnishing.
The final orbital sanding pass is important for parquet. It removes the slight grain-raising that can occur from the diagonal sanding direction and produces a surface that is consistent across both block orientations. This final pass should be done in two or three directions to ensure complete coverage.
Varnish Application on Parquet
Varnish application on parquet follows the same principles as on plank floors, but with one additional consideration: the seal coat application direction. Apply the seal coat across the diagonal of the herringbone pattern, which ensures that the product is worked into the grain of every block rather than gliding over the cross-grain blocks on alternate rows.
For the main varnish coats, applying along the full length of the room (which will be at a diagonal to the herringbone pattern) and maintaining a wet edge across the room area works well. Work with the length of the room rather than trying to follow the block pattern.
Between coats, screen the floor with 100-grit to 120-grit screen to remove grain raising and ensure good intercoat adhesion. This is the same process as for plank floors, and it is equally important on parquet.
Product Selection for Parquet
Bona Traffic HD is widely used on parquet floors and produces excellent results. Its extra-matt formulation is particularly popular on old oak parquet blocks where a very natural look is desired. For solid oak parquet that will be sanded and refinished periodically over many years, a quality two-component varnish like Traffic HD or Loba 2K Invisible provides the best durability per refinishing cycle.
- Sand herringbone parquet diagonally at 45 degrees to both block directions
- Finish with orbital sanding in multiple directions to remove machine marks
- Apply seal coat along the diagonal of the pattern
- Apply varnish coats along the room length, maintaining a wet edge
- Screen between every coat
- Bona Traffic HD extra-matt: excellent for traditional oak parquet
The patience required to prepare and varnish a parquet floor properly is repaid by a result that is beautiful and durable. Old parquet floors that have been poorly maintained or covered with carpet for decades can often be completely transformed by a professional sand and varnish, revealing extraordinary quality beneath the surface neglect.
