With all of the snow we’ve had here in New England lately, we’ve already seen a number of roofs collapse from the added snow load. Already this month in Massachusetts alone we have seen roof collapses at the Piano Mill in Rockland, a commercial building in Rockland, an industrial building in Canton, a former sportsplex building in Auburn, an Abington building, and an historic building in Hingham.
There are often, but not always, advanced warning signs that occur before a roof collapses. If you observe any of these signs, safely evacuate the building and have a structural engineer perform an inspection. Your building may be sending out warnings signs in advance.
Some Warning Signs
Visual Signs: If you notice anything new or usual such as sagging ceilings or beams, cracked wood beams or posts, bent posts, cracked plaster or sheetrock, misalignment of building elements, new gaps that have formed, doors that have become difficult to operate, bulging or curved walls, cracked or broken windows, light fixtures or sprinkler heads pushing down from the ceiling, bowed pipes or electrical conduit, pipe leaks or bursts (due to bending), new roof leaks, or water stains your roof could be in danger of imminent collapse.
Auditory Signs: Creaking, popping, cracking, repeated tapping sounds in the walls or ceiling, or any strange or unusual sounds.
Felt Signs: Things that are new or unusual such as cold drafts, spongy or bouncy floors, tilting or uneven floors, or any strange movements felt within the building.
The advanced warning signs listed represent only some possible signs that can occur. The absence of such signs does not mean that your roof is necessarily safe from collapse. It is also possible for a roof collapse to occur with little to no advanced warning signs at all.
To be safe, it is recommended that: 1) roofs be cleared of as much snow as possible in a safe and responsible manner by a qualified contractor using proper snow removal methods, and 2) an assessment be performed by a structural engineer to evaluate existing snow-load conditions when snow cannot be safely or practically removed. The engineer can evaluate the degree of danger and can help manage the situation with possible solutions such as added temporary shoring and bracing. Always err on the side of caution.
Written by Joel E. Breuer, PE managing partner at HG Cornerstone. Mr. Breuer can be contacted at firstname.lastname@example.org.