EHCI Learning & Certification
Cumaru technical profile
Cumaru (Dipteryx odorata): hardness, density, durability, movement, fastener and finishing guidance for exterior use.
- Botanical name
- Dipteryx odorata
- Origin
- Northern South America
- Janka hardness
- 3,330 lbf
- Density (12% MC)
- 1,085 kg/m³
- Natural durability
- Very durable
- Appearance
- Medium to reddish brown with interlocked grain and a waxy feel
Movement and stability
Moderate to high; kiln-dried stock recommended for decking to reduce checking and cupping
Working properties
Dense with interlocked grain; tearout on planing; pre-drill all fasteners
Fastener guidance
Stainless steel; hidden clip systems require groove tolerance checks due to movement
Finishing and weathering
Oil finishes adhere better after acclimation; expect natural color variation between boards
Common applications
Cautions
- Air-dried stock can move substantially after installation
- Acclimate on site under cover before fixing
Related guides
Sources: USDA Forest Products Laboratory, Wood Handbook (FPL-GTR-282); International Wood Products Association species guidance; Published supplier technical data sheets (values vary by origin and grade). Values are typical and must be confirmed with supplier documentation.