Snow-shelf structure
Snow-shelf structure
(OP)
I have a new roof that is approximately 3 metres higher than an existing roof. I have looked at many options to address the issue of accumulated snow load that would result on the existing low roof, but found that the most economical approach is to build a snow shelf. This structure is in Canada.
The snow shelf will be supported entirely by the new roof and will extend above the existing low roof by a distance of approximately 3.5m. I am adding a high parapet on the new high roof to reduce the required projection of the snow shelf to 3.5m.
What is the criteria for locating the height of the snow shelf?
Top of deck to match height of the basic snow load of the low roof?
Underside of shelf structure to match height of the basic snow load of the low roof?
The snow shelf will be supported entirely by the new roof and will extend above the existing low roof by a distance of approximately 3.5m. I am adding a high parapet on the new high roof to reduce the required projection of the snow shelf to 3.5m.
What is the criteria for locating the height of the snow shelf?
Top of deck to match height of the basic snow load of the low roof?
Underside of shelf structure to match height of the basic snow load of the low roof?






RE: Snow-shelf structure
RE: Snow-shelf structure
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RE: Snow-shelf structure
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RE: Snow-shelf structure
RE: Snow-shelf structure
@GalileoG>>>> You can avoid leeward drift on the lower roof by building a new screen wall / parapet of sufficient height.
However, as BadgerPE posted above, you still need to deal with windward drift on the lower roof (because of higher adjacent new construction).
Does the existing lower roof have parapet? This may provide some relief.
Qualitatively, the build-up of the windward drift on the lower roof will be reduced depending on the projection of the new snow shelf and the reduced length of the lower roof(lu per ASCE 7) upwind of the drift.