Attic Dormer High Snow Load

Most dormers are roof dormer windows that is the structure s roof surrounds the dormer as if it were a skylight.

Attic dormer high snow load.

Load path roof dormer the load path from the dormer flows down the side wall. However the side wall does not extend to the floor in this area. Snow accumalates in valleys and may be a major design concern. Proper roof ventilation and high r value roof insulation is essential to minimizing ice dam formation.

One reason may be that the current unbalanced snow load provisions for gable roofs is much higher then what was required by some codes in the past. This was the cause of the long standing interior moisture issues. In areas where you might get 2 or 3 ft. Homes in non snowy areas usually come with 20 lb.

Accounting for snow loads in certain climates constructing roof dormers is relatively straightforward in both original design and renovations. Of snow you should upgrade to the 50 lb. However only a single rafter is placed here. These photos were taken by roxie baldwin in 2002 at mirror lake on the medicine bow routt national forest.

The load path needs to flow into the rafter next to the dormer side wall. And the extra heat is not just a summer concern come winter hot attic air can melt snow on the roof during the day only to refreeze when temperatures drop overnight creating ice dams that lead. If the dormer is built above living space rather than over an attic or if you re converting attic space to living space then it provides much needed natural light. In some cases roof snow melt systems or heat tape can be used to combat ice accumulation on eaves and in valleys.

Underestimation of snow loads can result in premature failure high maintenance costs resource damage and in some cases safety issues. In practice i found when a building only has a single valley on one side of the roof the unbalanced snow ussually governs. It is something you have to pay attention to in areas with snow. Shed dormers are easier to waterproof and shed snow better than gable dormers.

Of snow on the roof a 90 lb. Roof dormers add light. If this rafter is supporting the dormer roof it should. In the case of heavy snow and ice during the last bad winter that s even more ponding water than usual.

Summer and winter photographs of the same building.