Heritage masonry repointing & deck-membrane risk
Load-bearing clay-brick masonry whose original soft lime mortar erodes; loft conversions also add rooftop amenity decks over elastomeric waterproofing.
Pre-1930 masonry needs soft, lime-rich mortar; repointing with hard modern Portland-cement mortar restricts brick movement and causes the brick face to crack and spall.
What it means for you: Improper past repointing means ongoing spalling and facade repair; planters/furniture on deck membranes cause water ingress into the units below.
Check: Mortar type used in any past repointing, facade spalling, and rooftop-deck membrane condition.
