That weird brick arch over in the old Canton warehouse district finally made sense to me

I was staring at it for like twenty minutes trying to figure out the centering, and then I realized they'd built it in two halves against a temporary plywood backer, not a full wooden frame. The mortar joints on the underside are perfectly smooth. I'm rebuilding a small garden wall arch next week and I'm tempted to try this method. Has anyone here actually done a split arch like that before?

2 comments

2 Comments

diana_bell749d ago

Oh yeah, the "two halves against a temporary plywood backer" thing. I read a whole article about that method in an old masonry magazine. They called it a building line arch or something. The big trick is getting the plywood curve perfect so both halves meet cleanly in the middle. I'd be nervous about the key brick at the top slipping before the mortar sets.

murphy.lisa9d ago

Ever try using a couple of small wood wedges for that top key brick? I had the same worry on my last arch. I cut two thin wedges from a scrap piece of pine and tapped them in on either side of the key brick after I set it. It held everything tight until the mortar got a grip. Just pulled them out the next day and filled the tiny gaps.