Warning: Tested a bulk mortar additive on a 500-block wall and got a weird result

Picked up a 5-gallon bucket of this new liquid plasticizer from a supply house in Omaha last spring. Figured it would save time on a big retaining wall job. Mixed it per the instructions and the mortar stayed workable way too long, almost 4 hours. Set was so slow the first 3 courses shifted on me overnight. Had to tear down 80 blocks and start over. Has anyone else seen additives mess with set times like that?

2 comments

2 Comments

shane_wilson1mo agoMost Upvoted

Dang, that sounds like a real headache. Was the bucket clearly marked with any expiration date or batch number? I had a similar thing happen with a different brand where the additive had separated and I didn't shake it enough. Having to rip out 80 blocks sounds brutal, especially on a retaining wall where the alignment is so critical. Hope you got your money back on that stuff, because that's just bad business on their end.

mark_cooper29d ago

Yeah but did you check the consistency BEFORE you started mixing? Because that's the thing that gets me - if the additive had already separated in the bucket, you'd see it right away when you opened it. A thin watery layer on top or a thick sludge at the bottom is a dead giveaway. I ALWAYS give my buckets a good stir with a paint mixer drill attachment before I even pour a drop, even if the label says it's pre-mixed. Those manufacturers don't always get it right, and once you're 80 blocks deep, it's way too late. Did you notice if the bucket felt heavier on one side or had any kind of sediment settled in it?