can be stacked when they are fully loaded. They may also be fitted with a lid during stacking for stability reasons. By stacking pallet boxes on each other space can be used more efficiently, thus are able to save warehouse space and truck load capacity. Another advantage of pallet boxes is that the goods are stored safely and are not easily damaged during logistic movements and transport. Furthermore, there are collapsible pallet boxes from which the pallet walls can be laid flat on the pallet. In this way, less space is required during empty return transport. Bulk boxes are closely related; they are usually large separate boxes shipped on pallets. Alternative uses Old and discarded wooden pallets can be used in pallet crafts and various furniture pieces. Discarded wooden pallets should not be used for firewood or crafts unless it has been determined that the wood in these pallets has not been treated with wood preservatives, fungicides and/or pesticides. Various pyrethrins and propiconazole are common treatments for wooden pallets. In addition, imported palletized goods are routinely fumigated with highly toxic pesticides. During use, harmful materials or chemicals also may spill on the pallet wood and be absorbed. Craft publications have advised readers to use pallets to build a skateboarding obstacle called a manual pad, barricades during amateur paintball games, or other sport-related items. Other publications have suggested using pallet wood for small animal cages or fences. Pallet wood has been recycled for use as furniture wood by at least one company. The acoustic guitar maker Taylor Guitars once produced a high quality "pallet guitar" made from pallet wood, in order to demonstrate the importance of construction technique versus expensive exotic woods. I-Beam Design, an architecture and interior design firm based in New York, NY won an award in a 1999 competition sponsored by Architecture for Humanity for their submission of “The Pallet House”, a design solution to house the returning refugees of Kosovo. Full-scale prototypes of The Pallet House were featured in the "Casa per Tutti" Exhibit at the Milan Triennale and the Earth Awards in HRH Prince Charles’ Royal Gardens as part of The Prince's Charities Foundation's Conference on a Sustainable Future organized in collaboration with IBM and The Financial Times. The Pallet House is an affordable transitional home that can become permanent over time. It can be used as refugee housing or as affordable housing as well. Due