The Owner’s Property Manager’s Guide to Dealing with Snow
By Eric R. Kizak, P.E.
In New England the first week of January is the traditional start of the snow sports season. Unfortunately, to the dismay of winter outdoor enthusiasts, this year’s season has started off with much less snow as compared to other years. But, sooner or later, significant snows will arrive in New England this winter and when they do building Owners and Property Managers will quickly recall snow removal operations and the many roof failures last winter brought. The following is a guide for the Owner and Property Manager, which if followed, will reduce the panic calls and haphazard approach that were so prevalent last year.
Before the snow:
- Pre-negotiate fees for structural investigation services and a roofing contractor for possible snow removal so that they are available when needed. You will likely receive a better price if you pre-negotiate and will have the time to evaluate credentials and experience. It is advisable that a roof contractor be hired because they are familiar with roof systems and are trained on how to avoid damaging roof during the snow removal process.
- Maintain complete records on your building’s structure and roof system. These records should be scanned and available for electronic distribution. Plans should include any alterations or modifications to the roof structure as well as both the original and current roofing systems. These documents will be used by your engineer to assess the capacity of the existing systems and to determine the extent of snow removal that is necessary.
- Locate, on existing plans, the position of roof drains, scuppers, mechanical systems, etc. or create a roof plan indicating the same. This information will be used by the engineer and snow removal crew to coordinate the process and limit the work to only the necessary areas.
After the snow:
- Monitor the weight of snow on the roof. Your engineer can make periodic direct measurements of the weight of snow for an accurate assessment or the weight of snow, or estimate the snow load based upon published meteorological information. When assessing the weight of snow it is advisable to section the roof into quadrants and take a measurement in each. Measurements should be taken at locations of average depth since in most newer buildings drifting snow is accounted for in the basic design.
- Monitor the roof structure for indications of overload. Indications include, displaced or dropped ceiling tiles, excessive deflection, bowing of nor-bearing partitions, and broken pipes or conduit. If any of these are observed, call your engineer to evaluate the snow loads and put your snow removal team on standby.
If the structural engineer has determined that snow removal is prudent, there are two primary considerations:
- What is the minimum amount of snow that needs to be removed?
- How do you remove the snow without damaging the building or endangering the workers?
The answer to the first question will be provided by your engineer, but in general, snow doesn’t need to be removed from the entire roof and should never be removed to the roof membrane. Under most situations snow removal will only be necessary in the middle of the beam/joist spans and around roof drains.
If the above recommendations are followed the all parties can enjoy the winter’s snows knowing that when we have large snow accumulation that procedures are in place to protect your structure.
And as a winter sports enthusiasts, I say “Let’s prepare and let it snow.”