KNAUF Ceiling Solutions Armstrong Woodworks Grille wood ceiling panels give any room an elegant, linear look. Made with a rapidly renewable natural bamboo core, these warm, natural wood ceilings come in pre-engineered horizontal slats or vertical blades. Install these wooden grilles on the ceiling, on the wall, or create 90º angled ceiling-to-wall transitions. Also available in acoustic options to lower noise reverberation and create quieter spaces.