Care should be taken when specifying these materials because some may off-gas toxins, such as formaldehyde, from their binding agents. These engineered wood products are more resource efficient and durable than solid wood. Systems where the cladding, substrate, insulation and even structural components are combined into preassembled, premanufactured components are often developed to provide a more efficient use of materials, more sophisticated thermal and moisture protection and ease of application. While these characteristics support a sustainable strategy, it is important to evaluate them in terms of the environmental qualities of the individual materials, their embodied energy and the energy required to assemble the composite system. Manufactured wall and roof panel systems, typically made up of a rigid insulation core sandwiched by sheathing materials are a potentially energy and resource efficient product.
Some systems are structural and can replace wood or metal framing.
While their R-values are only slightly higher than fiberglass batts used in traditional stick framing, the panels' resistance to infiltration provides a tighter envelope than traditional framing. Sheathing materials on these panels can be anything from stainless steel to recycled aluminum, plywood, waferboard or homosote. Efficient material use, energy conservation, and ease of construction make this group of products worth considering. Use products that come from sustainable sources or those made with recycled material. Take into consideration environmental impacts of manufacture, use and disposal of any product.