The main factor that may weaken the stability of the roof structure is dampness. On its negative impact it is particularly exposed rafter framing, which deform under impact of water. Therefore is important roof protection against getting in  water into its internal structure.

Typically, investors during the construction of the roof attach great importance both for building materials, as well as careful execution. Unfortunately, later very often they forget about the survey, and any minor defects  commission outsource cheaper and often non-professional roofing companies. This is a big mistake,

Walkersville Covered Bridge Wikipedia, the free encyclopedia Walkersville Covered Bridge is a historic covered bridge near Walkersville, Lewis County, West Virginia. It was built in 1903, and is a Queen post truss bridge e Rd, Walkersville, Public Property. See the sales history forGlade Rd, Walkersville,

A very important element that must be considered when the roof is projected, is ventilation, allowing drainage of excess dampness from under the roofing.