Why dirty work always comes first

Demolition, chasing walls for services and screeding produce fine dust that settles on every exposed surface, however far it seems from the work area. If fine finishes (wood flooring, paint, wallpaper) are already in place when this messy work starts, dust and debris damage them directly, sometimes irreversibly.

Screed and plaster release moisture into the air as they dry, a process that can take weeks depending on thickness and conditions. Laying wood flooring or wallpaper over residual moisture that hasn't fully dried leads to warping or detachment that shows only months later, long after the job seems successfully finished.

Redoing a finish damaged by messy work done afterwards almost always costs more than following the right order from the start — not only the lost material, but double labour (removal, then refitting) and the extra time lost.

There are legitimate cases where some finishes go in earlier than the classic order — for example a room completely sealed off from the rest of the site with no more messy work scheduled. These exceptions need a careful assessment of the real risk, not just the wish to hurry a deadline, which is the most common real cause of wrong reversals.