In message , Chris J Dixon
writes
wrote:


It's called "scribing". Put the timber in place, propped in places if
necessary, then find a small spacer that's the size of the smallest gap.
Rest a pencil on the top of the spacer and run the spacer along the
floor so that the pencil draws the floor profile on the wood,

Shouldn't that be the largest gap, otherwise you won't reach the
timber? ;-)
Quite.
Having done this and carefully trimmed exactly to the line, consider
that you will be placing unsealed mdf/chipboard in intimate contact with
a floor which diligent wives are likely to dowse with water at regular
intervals:-)

No doubt someone will suggest a precautionary sealing tactic.

--
Tim Lamb