What is EHCI Certification Manager?

EHCI Certification Manager manages 5 data types including bundle links. Helps you organize, track, and share your work in 1 place for teams and solo users.

Installation

Struggling with End Checking on Cumaru: Sealing Method Feedback

Tyler Morrison Jul 6, 2026 at 10:34 PM

Just wrapped a 400sqft Cumaru deck in humid Florida and I'm hitting a wall with end checking. Even after giving the ends a fresh cut, I'm seeing splitting within 48 hours of installation. I’ve been applying Anchorseal to every cut on site, but the heat is just brutal right now. Is anyone else finding that the current supply of Cumaru is checking worse than previous seasons? I'm debating whether to switch to a different wax-based emulsion or if I should push the client to trim the boards back further during the final finish. I used to rely on standard paraffin, but it’s not holding up in this 90-degree heat. Are you guys having better luck with specific brands like Anchorseal Classic versus the newer formulations? Any tips on application timing—should I be sealing the second I trim, even before the boards hit the joists?

2 Replies

Grant EllisonJul 8, 2026 at 10:34 PM

Honestly, Florida humidity is brutal on Cumaru. I stopped trusting Anchorseal for the Florida summer heat years ago. I switched to Anchorseal 2, and the key is applying it within seconds of the cut—literally have the brush in hand before the saw stops spinning. Don't let those end grains sit open in that sun for even a minute. If you’re really struggling, try double-coating the ends. Some guys like using high-end end grain sealers like Woodlife CopperCoat underneath the wax, but in this heat, the speed of application matters more than the specific brand. Keep at it, it's just the nature of the beast.

Rachel WoodJul 10, 2026 at 10:34 PM

Rachel Wood: I’ve been dealing with Cumaru in the Southeast for years, and I stopped relying solely on wax a while back. In this Florida heat, I’ve found that using a two-step process works best: apply a coat of an oil-based end grain sealer first to penetrate the fibers, then follow up with a thick layer of a premium emulsion once that’s tacky. Also, are you checking your moisture content before install? If the stock is coming in drier than the ambient environment, it’s going to move no matter what you do. I’ve started storing boards under shade cloths on-site to keep the surface temperature down during the install.