Cumaru is a very dense, extremely hard-wearing timber suited to a variety of internal and external applications across residential, commercial and structural/civil construction. Cumaru is also known as Tonka or Brazilian Teak. Compared to other hardwoods only negligible tannin bleeding occurs.
Cumaru is an extremely strong timber, strength graded for F34 (beams) and F27 (posts). This enables longer spans, reduces number of posts and saves you money for on site labour. Cumaru has a very high density of 1085 kg/m3 which means it meets the specified density as specified in AS 3959-2009 for use in timber construction in bushfire zones up to BAL 19. Cumaru is also termite-resistant.
Cumaru is an attractive timber, with a unique interlocking grain. Mid-brown in colour with a reddish or purple hue when cut changing to brown with red or gold flecks. It can age to a lustrous grey if left uncoated.
Pre-drilling for screwing or nailing when installing decking is recommended. Its inherent hardness has a blunting effect on tool cutting edges, therefore saws/chisels/drills etc. need to be sharpened more often. It can be sanded, oiled and painted very easily. Porta recommends using an oil-based paint/stain preparations due to its high timber density, as water-based products have minimal penetration for long-term coating durability. Compared to other hardwoods tested Cumaru demonstrated no apparent or negligible tannin bleed. However Porta recommends cleaning of timber prior to installation and a suitable sealer to protect the timber and minimise any potential run off of natural resins onto surrounding surfaces.
Is Cumaru suitable for in-ground applications like posts etc?
Cumaru is ideal for use in external application such as posts and landscaping. For maximum performance, set posts in concrete to protect it against water. In landscaping applications provide good drainage and protect the timber from static water, where possible.
How does Cumaru stand up to UV or sunshine exposure?
Porta Cumaru has been used in external exposed application such as board walks and wharves, for many years. Our trial show Cumaru withstands severe weather exposure and our experience is that it is highly durable. Read more about Cuamru in the Atlantic City Boardwalk case study.
Can nailplates be used with Porta Cumaru?
Yes, Porta has conducted laboratory nailplate fixing trials and found the nailplates can produce a stable joint when used with Cumaru timber.