Luan Wood Waterproof?
I have written extensively on this blog that Luan Wood does not respong well to Water Exposure as it tends to warp and degrade the material. In fact this is why you should only use Luan Wood as a underlayment for Vinyl or Laminate Flooring on not for Ceramic or Tile, where the wood will get wet during the installing process. The Wood / Plywood Associations have made a note that Luan Wood has not been fully tested, and has not achieved any grading from the organizations.
How to Bend Plywood
Luan Wood Video Series
Bending Luan Wood Video
Installing Luan Wood Video
Cutting and Installing Vinyl Over Luan
Installing Luan Over Subfloor
Laying laminate over Subfloor
Making Tile Flush With Subfloor
Attaching Luan To Subfloor
Working With Luan For Do It Yourselfers
There are reports that using Luan Plywood as underlayment for Tile is unacceptable. This is because some believe that because Luan Plywood is made of an unacceptable and unapproved substrate that it cannot receive tile or cementitious backer units. Now I've written on this blog that Luan Plywood doesn't react well to moisture that is a sure part of the process when laying ceramic tile flooring, so this is no surprise the readers here. Ceramic, Tile, Stone or any other product with a cementitious backer unit should not use any Luan Wood as stated by the general body making guidelines for the flooring and hardwood industries.
Furthermore they state that for the abovementioned materials, Luan products are not made and manufactured under any recognized grading rules or measures. As well it is not recognized by the building codes or organizations and does not carry a grade stampe or have any structural design value.