Shoutout to the guy who showed me a different way to handle expansion joints

For years I cut them with a saw after the pour, which always left a rough edge and took forever on a big slab. Last fall on a warehouse job in Spokane, the crew lead had us set pre-formed foam strips before the pour and just trowel right over them. It cut our finishing time by about two hours and the edges were clean. I'm sold on the new way, but my old boss swears by the saw method for control. What's your take on pre-formed versus cut joints?

3 comments

3 Comments

evan_wilson1811d ago

Wait, is your old boss talking about control joints or expansion joints? Those foam strips are for isolation joints, not really for control (which you cut). For a big warehouse slab, you'd probably use both. The foam is great for edges against walls or columns, but you still need to cut control joints in the field to force the concrete to crack in straight lines. The saw method gives you more control over where those cracks happen.

terry_carter154d ago

Wait, he was calling the foam strips control joints? That's a huge mix up.

eric72311d ago

Exactly, and if you skip those saw cuts, the slab will still crack, just in random ugly lines that ruin the finish.