What happens when modern cement mortar is used on an older property that was originally built with lime?
In this section from the upcoming Episode 2 of The Healthy House Podcast, Jake Mitchell from Archer Brick & Stone explains the difference between lime mortar and cement pointing, and why using the wrong material can cause lasting damage to traditional masonry.
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Highlights
Many period properties, particularly those built before the 1920s, were designed using lime mortar. Lime is more permeable, allowing moisture to move through the wall and evaporate naturally. When harder cement mortar is introduced, moisture can become trapped within softer bricks or stone, potentially leading to saturated masonry, crumbling mortar, spalling and damaged brick faces.
Jake also shares examples from residential properties and restoration work where previous cement repairs made removing damaged bricks more difficult and increased the risk of further damage.
The conversation explores traditional repointing, permeability, freeze-thaw damage, identifying different mortar types and why mortar should act as the sacrificial part of an older wall.
Understanding the age, construction and original materials of a building is essential before carrying out masonry repairs.
This clip is taken from Episode 2: Brick by Brick: The Truth About Traditional Homes - EP 2 Jake Mitchell - Archer Brick & Stone.
