Hello roger and thank you for your question.
The manufacturer does not recommend installing this product in full bathrooms, however it can be installed at ground level and below grade. Engineered wood should be treated like real wood: any water that is exposed to the surface should be wiped up immediately to prevent product damage. The bath should also have a fan to minimize humidity changes when the shower is used. Moisture test as recommended before starting any installation.
The Installation instructions are located here: http://www.armstrong.com/pdbupimage...
Best wishes on your project.