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,

ArizonaBoys pose for the photographer on a string of coal cars parked on the turning wye that used to run along Campbell Avenue in this photo looking east around 1892. Solar water distillation MOTHER EARTH NEWS The other common type of solar distiller is the multibasin

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