If waterproofing is compromised, a seal won’t hold, and tiles must be removed to reapply the waterproofing membrane. Signs of compromise include cracked, loose, or drummy tiles, mould, discolouration, odour, or water dripping under the floor. Sometimes these signs aren’t visible, but once we remove grout to attempt a seal, we can uncover underlying waterproofing issues that then require tile removal for proper repair.