To get a level floor we have applied a latex leveling compound to the floor. This tends to cover the cut outs in the joists where the underfloor heating pipes travel across them so first of all we took digital pictures of all the pipes in all the rooms.
Then we have made simple drawings with dimensions of the cut outs prior to latexing, and then used these to mark up the floor on the latex to show where we must not put nails!
The floor nails using the secret nailing method will go in at about 45 degrees so you have to allow for the horizontal travel when looking at where to put a nail in.
As an extra precaution as the position of the joist can sometimes be concealed, we have drawn lines with the felt marker to show where the joists are too. After all, if we went through a pipe it would be a major job to repair the pipe.
