Cumaru (Brazilian Teak)

Cumaru (pronounced "koo-MAH-roo") is a dense tropical hardwood that delivers performance remarkably close to Ipe at a significantly lower price point. With a Janka hardness of 3,540 lbf, Cumaru is one of the hardest woods commercially available and has become the go-to choice for builders who want tropical-grade durability without the Ipe premium.

Cumaru decking boards showing warm golden-brown color

Color & Appearance

Cumaru heartwood displays a beautiful range from golden-tan to reddish-brown, often with darker streaking that adds character and depth to a finished deck. The grain is typically interlocked, producing a medium to fine texture with a natural luster. Like all tropical hardwoods, Cumaru will weather to silver-gray if left unfinished, or the warm tones can be preserved with annual UV oil treatments.

Cumaru vs. Ipe

The honest comparison: Cumaru is 95% of the wood that Ipe is, at roughly 70% of the cost. Both carry Class 1 durability ratings and Class A fire ratings. Both resist rot, termites, and marine borers. The primary differences are aesthetic — Cumaru trends warmer and more golden, while Ipe runs darker and more chocolate-toned. Cumaru also has slightly more color variation board-to-board, which many homeowners actually prefer for a more natural, less uniform look.

Available Profiles

1x6 Pre-Grooved Decking: Our standard residential Cumaru profile. Edge-grooved for hidden Ipe Clip fastening. 5.5-inch exposed face. Standard lengths 8'–18'.
1x6 S4S (Square Edge): Traditional face-screw decking. 5.5-inch exposed face. Required for stair treads and perimeter boards where hidden clips cannot be used.
1x6 Tongue & Groove: Milled for porch ceilings, soffits, and paneling. 5.0-inch exposed face width. For covered use only.
1x4 Decking: The classic Northeastern architectural profile — a refined, linear aesthetic highly sought after in modern custom home building. Not limited to light traffic; this is a full-performance decking board. 3.5-inch exposed face.
1x4 Tongue & Groove: Covered porch flooring. 3.0-inch exposed face.
5/4x6 Pre-Grooved: Heavy-duty commercial and extreme-load profile; many builders and homeowners also choose it for residential decks. Edge-grooved for hidden clip fastening. 5.5-inch exposed face. Standard lengths 8'–18'.
5/4x6 S4S (Square Edge): Heavy-duty face-screw profile for commercial and dock applications. 5.5-inch exposed face.

Cumaru deck installation showing rich reddish-brown tones

Close-up of Cumaru wood grain and color variation

Performance Specifications

Janka Hardness: 3,540 lbf
Density: ~66 lbs/cu. ft.
Durability Class: Class 1 — naturally rot-, decay-, and insect-resistant
Fire Rating: Class A (ASTM E84)
Expected Lifespan: 30–50+ years
Grading: Premium Grade

Fastening Ecosystem

Cumaru requires the same installation approach as Ipe — pre-drilling is mandatory, and only stainless steel fasteners should be used.

Ipe Clip Hidden Fasteners: 175-count Complete Kit covers exactly 100 sq. ft. Our standard kits feature the 5/32-inch gap brown clip, designed to disappear into the natural shadow lines of tropical hardwoods.
Smart-Bit Pre-Drill Tool: #7 (flush) or #8 (countersunk). 1 per 100 sq. ft. (1 per box of screws).
Pro Plug System: 5/16-inch Pro Plug tool. 1 per 100 sq. ft.
Hardwood Plugs: 100-piece box of 5/16" plugs, matched to linear footage of S4S perimeter and stair treads.
Face Screws: Our most common choice is #7 x 2-1/4" trim-head stainless steel (350-count box per 100 sq. ft.). Other options are available if you prefer.
End Seal: Seal all cut ends immediately to prevent checking

Railings & Accessories

For custom railing profiles and dimensions we use Ipe; contact us for availability. Pair Ipe railing with a Cumaru or Ipe deck for a cohesive tropical-wood exterior.