Steven L. Smith, Bellingham, WA Home Inspector (King of the House)

It might vary in different areas, but around here, most of the siding one finds on manufactured homes is oriented strand board. It is commonly called OSB. By the way, the famous siding that had so many problems -- L-P siding, was oriented strand board. Even though they have done some work on the composition of it, anytime OSB is seen, it needs to be carefully gone over. Very seldom, especially on manufactured homes, do I find OSB that does not have at least some decay. This material, when it gets wet not only decays but it almost reverts to a form of cardboard. It is soft and you can put a probe right through it with the greatest of ease. With this product, good eaves help protect the siding. It also needs to be carefully maintained and paint and caulking kept in good shape. Downspouts dumping on the siding, dirt on the siding -- while bad with any wood siding -- are about 5x worse with this product. It should not be surface nailed and holes for hooks or planters on the side are invitations for trouble. If one had such a home in a very dry climate, with little rain or moisture in the air, some of these warnings might be less critical concerns. This information is passed along as a number of realtors have posted information on mobile and manufactured homes. A photo of OSB on a manufactured home is below. It looks much like T1-11 siding (a veneer (in sheets or layers) like plywood) to the untrained eye -- but they are different products. OSB is ground-up flakes of wood all glued back together. I will be writing a blog on that issue shortly.

Typical manufactured home with OSB, sometimes we see various metal sidings, but this is the norm