Materials
Floorboard rows & balanced edges
- where
- usable width (mm)
- room width (mm)
- gap at each wall (mm)
- row count
- effective board cover (mm)
- equal edge-row width (mm)
Explain this equation
Sets out floorboard rows across a room so that the first and last rows are the same width. That avoids leaving a thin sliver against one wall.
W is the room width and g the expansion gap left at each wall. u is the usable width between gaps. c is the effective cover of one board, excluding the tongue. n is the number of rows, and e the width of each of the two edge rows. All are in millimetres.
Taking 2g from the room leaves the width to be filled. Dividing by the cover and rounding up gives the rows needed. Of those, n − 2 are full boards, and the space left over is split equally between the two edge rows.
A 3000 mm room with 10 mm gaps and 150 mm cover leaves 2980 mm and needs 20 rows: 18 full rows plus two edge rows of 140 mm.
Watch out: if only one row is needed, the calculator reports the full usable width. Check the product's minimum rip width.
Set out equal first and last rows across a room.
Enter your values to see the result.
Good to know
Cover width excludes the tongue. For one row the full usable width is reported. Confirm product minimum rip width and support. Expansion gap is a specified input.
Limits
Flooring gaps, slide clearances, fire-door gaps, fixing schedules and finishes must follow the design and product instructions.
Sources
This is a calculation aid, not a structural design or compliance certificate. Every default is an example, not a specification for your project.