How do I lay the first row of flooring against a wall that is not straight?

Almost no wall in a British house is straight, and a floating floor laid tight to a bowed wall inherits the bow — which then grows across the room, because every subsequent row follows the first. Scribing takes half an hour and it is the difference between a floor that is square to the room and one that visibly leans.

What you'll need

• a chalk line or a long straight edge
• a scribing block or a compass
• a jigsaw or a circular saw with a guide
• spacers
• a pencil

Step by step

1. Find out how bad the wall is.Pull a string line or lay a long straight edge along it. Measure the gap at the worst point. Under a few millimetres you can usually ignore it; more than that and it needs scribing.
2. Decide the reference line for the whole floor.Usually a line parallel to the most visible wall, or squared off the main sightline. Snap it on the subfloor. Every row will be laid to that, not to the wall.
3. Dry-lay the first row along the reference line.Boards clicked together, sitting with their back edges towards the wall, positioned so that after scribing they will still leave the expansion gap everywhere.
4. Set the scribing block to the widest gap plus the expansion gap.The block or compass is opened to that distance. That setting is what guarantees the gap is maintained at the worst point on the wall.
5. Run the block along the wall with a pencil against it.Keeping the block in contact with the wall and square to it, draw a line along the board. The pencil line is now a copy of the wall's shape, offset by the expansion gap.
6. Number the boards before lifting them.They only fit where they were. A row of unnumbered scribed boards is a puzzle.
7. Cut to the line.A jigsaw for a curved scribe, a circular saw with a guide for a straight taper. Cut just to the waste side of the line and take the last of it back with a plane or a sander if needed.
8. Re-lay the scribed row on the reference line and check.The gap should now be roughly even along the wall and never less than the expansion gap. Spacers hold it while you work.
9. Continue as normal, laying every row to the previous one.The floor is now straight, and it stays straight because each row follows the last rather than the wall.
10. Check the far wall before you get there.If the opposite wall is also bowed, the last row will need scribing too. Knowing that now lets you leave enough width for it.

Tips

• In a bay or an alcove, scribe a card template first and transfer it to the board — much cheaper than learning on the flooring.
• If the wall is very bad, consider whether the skirting can absorb some of it: a thicker skirting hides a bigger gap.
• Where the flooring runs under a door frame, undercut the frame rather than scribing round it. Frames are far easier to cut than boards.
• Keep the tongue or groove you need for the next row intact — scribe on the wall side only.

Common mistakes

• Pushing the first row tight against the bowed wall — The row takes the shape of the wall, and every subsequent row follows it. By the far side of the room the boards are visibly not parallel with the opposite wall, and the last row has to be cut as a wedge to compensate.
• Scribing without allowing for the expansion gap — The scribe copies the wall exactly, so the boards end up touching the wall at the closest point. That is a pinch point, and it is enough to buckle a floating floor.
• Cutting the scribe off the tongue side — The row loses the profile the next row has to engage with. Always scribe the edge that faces the wall.

If it doesn't work

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