A traditional 2x4 made specifically from bamboo is less common than one made from traditional lumber like pine or douglas fir. However, there are companies that produce engineered bamboo products that mimic the standard dimensions of lumber used in construction materials like 2x4s. These engineered bamboo products are typically constructed by compressing and gluing together multiple layers of thin bamboo strips or fibers under high pressure to create dimensional stability similar to solid wood products. So while you may not find a natural solid bamboo 2x4 readily available at your local hardware store like you would with softwood or hardwood options; there are alternatives manufactured using engineered bamboo materials that are suitable for various construction applications.