Comparing Tropical Woods for Use in Outdoor Furniture

Utile, Sapele, and Ipe compared and contrasted. Which works better for exterior furniture? June 13, 2011

Question
I have a quote request for a custom cabinet/furniture piece for exterior use. The designer asked for options in Utile/Sipo, Sapele and Ipe. Does anyone have any comments as far as long term viability? Also in consideration is that the slab doors on front of cabinets will have to be a veneer laid up with epoxy on exterior grade MDF, if that makes a difference.

Forum Responses
(Architectural Woodworking Forum)
From contributor E:
I can't comment on Sipo/Utile , but I would avoid Ipe. The lumber I have seen under that name is rarely dried thoroughly, checks badly when dry and is unpleasant to work with- oily, brittle and full of festering splinters. The veneer should be dry, but has no better working properties. It has a good rep for durability meaning rot resistance, but is probably better suited for decking than cabinetwork. Sapele, I believe, is rated as moderately resistant to decay, as are Honduras mahogany and Spanish cedar. In my limited experience it is not as stable in use as those two woods in exterior applications.



From contributor K:
Regardless of material cost, the costs to manufacture out of Ipe are going to be much greater than any of the other selections. Any of the others should hold up outside just fine as long as they're not submerged and allowed to dry out after they get wet.


From contributor O:
Ipe, as imported, is a mix of several species similar in appearance and properties, traded under the common name. I am under the belief that some species called Ipe can be glued, others cannot. This comes from experience, but mostly from observation. I have seen one exterior project fail spectacularly when the epoxy formulated for the stuff failed. The woodworker was using deckwood Ipe. Your machining costs will be high, and employee annoyance will also be high since the stuff is an irritant.


From Gene Wengert, forum technical advisor:
Sapele does have very good insect and decay resistance (heartwood, not sapwood). Utile (or Sipo) is a kissing cousin of Sapele (same genus) - same properties roughly. Ipe has great resistance to decay and insects. Because it will be used in exterior, drying is not an issue. However, Ipe consists of a group of species that are in the TABEBUIA genus, so you can find some variability in color and properties. What you want is Ipe that is in the Lapacho group of species.