The difference a lime mortar mix made on my 1920s repoint job

Been doing brickwork for 15 years. Always used standard Type N mortar for repointing old houses. Figured it was fine. Then I got a call to fix a wall on a 1922 house in our historic district. Owner insisted on lime mortar. I was skeptical. After I mixed it up and started working it in, the difference was night and day. The old soft bricks weren't fighting the mortar at all. That was two years ago. I drove by last week and the joints still look perfect with no cracks. My normal mortar jobs always show hairline cracks after one winter. Anyone else switch to lime for historic work and see your repairs last way longer?

2 comments

2 Comments

tylerr3912d ago

You been doing this 15 years and only now found out about lime mortar? Yeah, that stuff is the real deal for old brick. I did a job on a 1910 church basement last spring with lime putty mix and it was like the wall was built for it. No fighting, no cracking, just clean joints that look like they've been there a hundred years. Your normal mortar is way too hard for old soft brick, it'll just crack and pull away every winter like clockwork. Once you go lime you never go back, man.

fiona_sullivan2912d ago

1908 was the year my grandma's row house went up, and that brick is softer than a sponge cake. I spent three summers scraping out cement mortar from a previous hack job before I could even think about repointing. Lime putty was the only thing that made that wall look right again after all that damage. You nailed it about the cracking thing too. That hard mortar traps moisture behind it and then the freeze thaw cycles just pop it right out. That church basement job you did probably breathes better than a lot of modern walls now.