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,

Yard Meets Garden in High Line Phase The Dirt Getting to know the High Line in New York City over the last year, it has been lovely to discover the back story the heroic efforts involved in saving the rail yard. The Hidden Glasgow Forums View

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