Removing heavy snow from your roof can prevent costly water damage to your roof, walls and ceilings. Water leaks from ice and snow are caused by interior heat from the house. Water from this melting is trapped and creates an ice dam on the roof, gutters and downspouts. The water then takes the path of least resistance and under the roof system, or sideways and through flashings which were not designed for ponded water. When this happens, interior water damage can occur. But unless you can do it safely, don’t jeopardize your well being by trying to remove it yourself. Leave it to a professional.
Some contractors may suggest that rock salt or calcium chloride be used to melt the ice and snow. This may cause unavoidable damage and many shingle manufacturers warn against this, as it may cause damage to the shingles and void the warranty.
Ice in gutters and downspouts are virtually impossible to remove without damage. In many cases, the gutter system has to be removed from the roof to allow for water to discharge.
Flat roofs whose drains freeze will trap water on the roof system. The trapped water may accumulate to levels higher than the roof flashings, resulting in water leaks. The downspout needs to be removed and possibly breaking open the drain, so there is discharge.
Skylights covered with ice and snow may cause leaking because of their “weep holes” being covered. Internal condensation can’t escape causing water. Have the snow and ice removed from around the skylight. Make sure the contractor is aware that there are skylights, so they don’t damage them if they are buried by snow.