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,

EADS Wikipedia, the free encyclopedia The European Aeronautic Defence and Space Company N.V. EADS was a global panEuropean aerospace and defence corporation that operated 2000–2013, and was. Airbus Group, Inc. Wikipedia, the free encyclopedia Airbus Group, Inc. formerly EADS North America represents the North American activities

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