Waterproofing & Damp-Proofing Quantities
Below-ground tanking, DPC/DPM lines, and wet-area waterproofing: how quantities are usually split in BOQs.
Typical BOQ splits
Below-ground works may separate preparation, membranes, protection boards, and drainage. Wet rooms need full-height vs partial tanking clarified.
Link to structural drawings for podium decks and planters—scope crosses disciplines quickly.
DPC and DPM are often linear metres by width type; cavity trays add corners and stop ends that are not obvious from area alone.
Below-ground tanking
Measure retained walls and slabs separately; water pressure and failure mode drive system selection, not just m².
Blinding, rebates, and pile caps need detailing—waterproofing often wraps penetrations with bespoke collars counted per nr.
Wet rooms and showers
Falls, hob heights, and drain positions affect sheet layout—quantities may include offcuts/waste higher than wall paint.
Flood tests and warranties may be preliminaries or separate testing items—read the spec.