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Rant: That historic church restoration in Boston used way too much mortar
I walked past a job last month on Beacon Street where they were repointing a 150 year old brick church. The mason was slapping on mortar joints thicker than my thumb. Everybody says you need a fat joint for old soft brick but that stuff was like 3/4 of an inch. I've worked with salvaged brick from the 1800s before and 3/8 is PLENTY if you mix the mortar right. That much extra just traps water and will blow the face off in a few winters. Who else has seen old timers overdo it on historic work?
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robin89611d ago
Wait are you sure that much mortar won't just ruin the whole point of the repointing? I mean I've heard the same thing about old brick needing a softer, more flexible mortar mix to keep from cracking under expansion and all that. But if you pile it on that thick, you're basically making a solid block of mortar that's gonna trap moisture against the brick forever. The whole idea of repointing is to let the building breathe, not seal it up like a Tupperware container. Those old bricks are soft and porous, so any water that gets in needs a way out, and a fat joint just holds it in until it freezes and pops the face off. Idk, maybe the mason thinks he's being safe by overdoing it, but that kind of work is just gonna cost more money later when the repairs fail.
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tessalane10d ago
Oh man, I gotta disagree a little here. I've seen plenty of old brick buildings that had thick repointing joints hold up fine for decades, especially if the mortar mix is right and the bricks aren't total mush. The real problem is usually the mix being too hard, not the joint thickness - a lime-based mortar that's softer than the brick can handle a fat joint without trapping moisture like you're saying. Plus, if the old joints were already that wide to begin with, trying to force a thin bead in there can actually create more gaps for water to sneak behind.
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