Calculate floor area

For a rectangular room, floor area = length × width: a room measuring 12 × 15 feet is 180 sq ft, and 4 × 5 metres is 20 m². For L-shaped, angled or irregular rooms, divide the space into simpler sections or draw the real outline in Parquet Planner and get the area instantly.

Rectangular room formula

Measure along the floor and keep both measurements in the same unit.

Length × width = floor area

12 ft × 14 ft = 168 sq ft.
4.2 m × 3.6 m = 15.12 m².

If you measured in feet and inches, convert the inches to a fraction of a foot before multiplying. Six inches is 0.5 ft, so a length of 12 ft 6 in becomes 12.5 ft. The planner can also work directly with inches for English-language projects.

L-shaped rooms

Split the L shape into two non-overlapping rectangles. Calculate each area and add them together. For example, 120 sq ft plus 48 sq ft gives a total floor area of 168 sq ft. Another valid method is to calculate the large outer rectangle and subtract the missing section.

Angled walls and fixed obstacles

A triangular section is base × height ÷ 2. Rooms with several angles quickly become difficult to calculate by hand, so drawing each corner can reduce mistakes. Areas beneath a fixed island, fireplace or column can be subtracted when they will not receive flooring.

Parquet Planner lets you reshape the room, add cutouts and manage several rooms in one project. It calculates the net floor area and perimeter automatically, then uses the same geometry to estimate the actual board layout.

Total floor area for several rooms

Calculate each room and add the results. In Parquet Planner you draw each room in the same project, and the project summary shows the total for all of them together – planks, packs and the area of flooring.

Square metres and square feet

One square metre is 10.764 square feet, and one square foot is 0.0929 m². A 20 m² room is therefore about 215 sq ft, and a 168 sq ft room about 15.6 m².

From area to flooring quantity

Floor area alone is not the amount you should order. Boards must be cut around walls, corners and openings, and flooring is sold in complete packs. Add an appropriate cutting allowance or simulate the layout before converting the required area into packs. The room shape, plank dimensions, direction and pattern can all change the result.

Draw the room and calculate area, boards, packs and waste together.

Calculate my floor area

Frequently asked questions

What is the formula for floor area?

For a rectangle, length × width. For other shapes, split the floor into rectangles and triangles (base × height ÷ 2), calculate each part and add them up.

How do I calculate the floor area of an L-shaped room?

Split it into two rectangles, calculate each and add them – or take the outer rectangle and subtract the missing corner. Both methods give the same answer.

How do I get the total floor area of several rooms?

Calculate each room and add the results. In Parquet Planner you can draw several rooms in one project, and the project summary adds them up for you.

Should I subtract a kitchen island or fireplace?

Yes, if no flooring goes underneath it. In Parquet Planner you add it as a cutout, and its area is taken off automatically.

How do I convert square metres to square feet?

Multiply square metres by 10.764. A 20 m² room is about 215 sq ft.

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