How much parquet do I need for 20 m²?

In a straight third bond about 21.2 m², that is 20 m² plus 6.1 % waste; with packs of 1.92 m² that makes 12 packs. In herringbone it is about 23.1 m² and 13 packs. Add one reserve pack either way.

How much waste should I allow for parquet?

In our simulation study a straight third bond came to a median of 5.7 %, 8.4 % in small rooms under 15 m² and 4.3 % in large rooms from 30 m². Herringbone came to 14.8 %. For diagonal laying, calculators and flooring forums give 15 to 20 %.

How do I work out the number of packs?

Floor area times (1 + waste in percent ÷ 100), divided by the coverage per pack, always rounded up. With several rooms each room gets the waste for its size and you round once over the total, because offcuts travel from one room to the next.

Does herringbone parquet need more material?

Yes, in the study's median about 9 percentage points more than a straight third bond, because every edge piece is cut at an angle. Short blocks lose less: oak blocks of 50 × 7 cm came to 8.5 % in herringbone, long planks of about 128 × 19 cm to 20 %.

Should I buy an extra pack of parquet?

Yes. The waste covers only the offcuts that can no longer be used, not breakage, a plank damaged while laying or a repair in a few years. Keep one pack from the same batch, because a later purchase often comes in a different shade.

Sunny flat with honey-coloured oak herringbone parquet in the living and dining area

Parquet calculator

Parquet flooring calculator: how much parquet do I need?

Floor area plus waste, divided by the square metres per pack, rounded up. For 20 m² in a straight third bond and packs of 1.92 m² that is 12 packs, in herringbone 13. The waste per room comes from our simulation study of 5,811 layout plans.

Parquet calculator

Each room gets the waste for its size; the packs are rounded up only once, over all rooms.

Room

Room length

Room width

Plank length

Default: the oak parquet plank from the layout planner

Plank width

Coverage per pack

m²

printed on the pack, for example 1.92 m²

Laying pattern

You need

Enter the length and width of a room.

Packs of parquet by room size

For packs of 1.92 m² and rectangular rooms, from the typical figure to the awkward case in one plan in ten:

Floor area	Straight, third bond	Diagonal	Herringbone
10 m²	6 – 7	6 – 7	7
15 m²	9	9 – 10	10
20 m²	12	12 – 13	13
25 m²	14 – 15	15 – 16	16 – 17
30 m²	17 – 18	18 – 19	18 – 19
40 m²	22 – 23	24 – 25	24 – 26

Straight and herringbone: median and awkward-case figure of our simulation study by room size. Diagonal: rule of thumb of 15 to 20 %. No reserve pack.

Worked example: a 5 × 4 m living room

Area: 5 × 4 m = 20 m², oak parquet planks of 120 × 20 cm, 8 planks per pack = 1.92 m² per pack.
Straight, third bond: 6.1 % waste for rooms of 15 to 30 m², so 20 × 1.061 = 21.22 m². 21.22 ÷ 1.92 = 11.05, so you order 12 packs.
Herringbone: 15.3 % waste, so 20 × 1.153 = 23.06 m². 23.06 ÷ 1.92 = 12.01, so you order 13 packs – one pack more.
Diagonal by the rule of thumb: 15 to 20 %, so 23 to 24 m² and 12 to 13 packs.
On top, one reserve pack from the same batch for breakage and later repairs.

The herringbone waste for your room size and shape is on the page herringbone waste percentage. For laminate, the laminate flooring calculator counts every plank and every cut, and how to lay parquet step by step is in the guide how to install parquet flooring.

For the edges, the skirting board calculator counts the boards, the corners and the end caps for the same rooms.

Floating parquet needs an underlay: the underlay calculator gives the rolls and the vapour barrier film for the same rooms.

Frequently asked questions

How much parquet do I need for 20 m²?: In a straight third bond about 21.2 m², that is 20 m² plus 6.1 % waste; with packs of 1.92 m² that makes 12 packs. In herringbone it is about 23.1 m² and 13 packs. Add one reserve pack either way.
How much waste should I allow for parquet?: In our simulation study a straight third bond came to a median of 5.7 %, 8.4 % in small rooms under 15 m² and 4.3 % in large rooms from 30 m². Herringbone came to 14.8 %. For diagonal laying, calculators and flooring forums give 15 to 20 %.
How do I work out the number of packs?: Floor area times (1 + waste in percent ÷ 100), divided by the coverage per pack, always rounded up. With several rooms each room gets the waste for its size and you round once over the total, because offcuts travel from one room to the next.
Does herringbone parquet need more material?: Yes, in the study's median about 9 percentage points more than a straight third bond, because every edge piece is cut at an angle. Short blocks lose less: oak blocks of 50 × 7 cm came to 8.5 % in herringbone, long planks of about 128 × 19 cm to 20 %.
Should I buy an extra pack of parquet?: Yes. The waste covers only the offcuts that can no longer be used, not breakage, a plank damaged while laying or a repair in a few years. Keep one pack from the same batch, because a later purchase often comes in a different shade.

Count the exact waste for your room

Upload your floor plan and the free planner works out the exact packs and waste before you order.

create a layout plan

Sources: Autolay simulation study, 5,811 layout plans, October 2026; diagonal: rule of thumb from calculators and flooring forums; pack size: oak parquet plank from the layout planner.