The mortar mix we used on the old city hall job versus the new library addition

We worked on the city hall restoration about five years ago, and the mortar was a classic lime-rich mix, you know, the slow-curing kind. For the new library wing last month, the specs called for a modern, pre-blended mortar with additives for faster set. The difference in speed was huge, like we laid three times the brick in a day. But I'm worried the new stuff won't have the same flexibility over 50 years. Has anyone else had to switch mixes for a job and seen a trade-off between speed and long-term durability?

3 comments

3 Comments

caleb24124d ago

Yeah, that "trade-off between speed and long-term durability" is the real question. We used a fast-set mix on a commercial job and it saved weeks, but I keep wondering if it'll crack in twenty years when the building settles.

murray.ray24d ago

Everything's built to fail faster now.

tessa_kelly3d ago

Man, I used to be all about that speed, you know? Get the job done fast and move on. But seeing some older brickwork from like the 1920s that's still perfect, while newer stuff is already cracking, really made me stop and think. That slow lime mortar moves with the building forever, it's like it's alive. The fast stuff just gets hard and brittle, and then it fights every little shift. Now I see why the old way lasted a century.

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