Ipe vs. Cumaru: A Side-by-Side Comparison for Deck Builders

Two Great Species, Different Realities

Ipe and Cumaru are the two most popular tropical hardwoods for exterior decking in North America. Both are dense, durable, and beautiful. But if you're treating them identically on the job site, you're probably running into problems.

After years of working with both species and reviewing feedback from certified professionals in the field, here's what actually matters.

Density and Working Properties

Ipe (Tabebuia spp.) typically ranges from 1,050 to 1,100 kg/m³. Cumaru (Dipteryx odorata) is close—usually 1,000 to 1,070 kg/m³—but it tends to be slightly more variable within a given board.

What this means in practice:

• Pre-drilling is non-negotiable for both. But Cumaru can be slightly more forgiving with bit sizes
• Blade wear is significant with both, but Ipe tends to dull carbide tips faster
• Cumaru is generally easier to sand to a smooth finish

Dimensional Stability

Here's where things diverge. Cumaru has a higher tangential-to-radial shrinkage ratio than Ipe, meaning it's more prone to cupping if not properly acclimated and installed.

For deck installations:

• Allow adequate acclimation time—Cumaru may need more time than Ipe in humid climates
• Gap spacing should account for Cumaru's slightly higher movement potential
• Face-screwing with proper pre-drilling is often more reliable for Cumaru than hidden fastener systems

Color and Aging

Fresh Ipe ranges from olive brown to nearly black. Cumaru tends toward a warmer golden-brown with reddish undertones. Both will silver to a similar grey if left unfinished.

The key difference: Cumaru's color variation within a shipment tends to be wider than Ipe. If your client expects a uniform look, discuss this upfront and consider a penetrating oil finish to even the tones.

Cost Considerations

Cumaru typically runs 15-30% less than Ipe per board foot. For budget-conscious projects, this can be significant—especially on larger decks. But don't position it as "cheap Ipe." It's a distinct species with its own strengths.

The Bottom Line

Both species are excellent choices. The difference is in the details—acclimation, fastening, finishing, and setting proper client expectations. Understanding these species-specific nuances is exactly what EHCI Level 2 certification covers.