What are the most common construction defects?

By volume, finishes: paint defects, plaster cracks, nail pops, skirting and joinery gaps. By consequence, wet rooms: sealant and grout failure, trays that move, missing upstands. Then doors and windows out of adjustment, ceiling stains, external ground levels bridging the damp-proof course, blocked or missing drainage, electrical accessories and, the one that matters most and is found least, missing fire stopping. Our field guide lists forty of them by trade with a severity band each.