The Manufactured Housing Forums

A while back I outlined plans to strip off the shingles and osb board off my double wide and add more insulation and also more breathing room for eave vents to roof vent. A lot of ice build up was the main problem. Plus we froze pretty much each winter. But a couple weeks ago I seen a contractor with the building inspectors okay, useing 2"X12" roof rafters at 24" spaceings, 7/16 osb board, at a pretty impressive pitch, ridge vents and he said 18 inches of blown in insulation. The outside walls held all the weight of the new roof and made a sturdy enough roof system so you could build an addition on and not worry about the strength of the rafters as you would with the trusses built out of two by two lumber. Sounds good and is okayed here in Michigan. My question is the air space between the original insulation and the underside of the old roof. Would there be a moisture build up here. It seems like pretty much dead air space with no ventilation. Any ideas would be appreciated. Thanks
Dan from Mi.

This does create a condensation problem for the reason you suggest. Even though your local building inspector approves this roof it would void the hud approval of your home.

Add a vented ridge cap to your plans with a venting into the old roof/ceiling space.

At this point with the roof you intend to build you will not be moving this home again and the HUD approval is no longer significant, as long as what your adding is structurally sound.