Tag Archives: ice on roof

When is it Time to Remove Roof Snow?

Regardless of what side of the climate change argument one is on – it has been snowing in Massachusetts this winter.

A lot.

Late January’s Winter Storm Juno alone brought up to 36 inches of snow in some parts of Massachusetts. https://www.weather.com/storms/winter/news/winter-storm-juno-snow-totals-wind-gusts

As if Juno wasn’t enough, another storm followed – leaving so much snow on the ground it forced the postponement of the celebratory parade through Boston for the Super Bowl Champion New England Patriots. https://www.cbsnews.com/news/flash-freezing-now-the-big-concern-in-northeast/

So, how much snow is too much for one’s roof?roof snow

As a basic rule of thumb, consider saturated snow weighs in at approximately 20 pounds per cubic foot. This weight is based upon a 25% moisture density, which may be conservative or liberal, as the actual moisture content of snow can range from approximately 1% to 33%.

Using the 20 pounds per cubic foot, this means every inch of snow will add 1-2/3 pounds per square foot of weight!

Any ice build-up on roofs would need to be added in as well. Use 5.2 pounds for each inch of ice depth.

For those who want to get scientific, the actual roof snow load can be checked by cutting a one foot square the full depth of the snow and ice build-up on the roof, dumping into a plastic bag and weighing the contents.

Modern buildings are designed for a snow load which assumes the roof snow load will be exceeded anywhere from once in 25 to once in 100 years, depending upon the Risk Category of the structure. The actual International Building Code language on risk categories can be read at: https://publicecodes.cyberregs.com/icod/ibc/2012/icod_ibc_2012_16_par023.htm

Buildings which were not constructed under Code requirements are often at far greater risk to collapse under snowfall. When rain falls upon snow, the weight of the roof snow can increase rapidly. Heating a building, in an attempt to melt the snow off a roof, can result in ice dams at the eave sides of the building – compounding the load problems.

Please be aware of the potential dangers of shoveling or raking snow from a roof. Besides the potential damage to the roofing materials and structure, there are such factors as a person sliding off the roof, falling off a ladder, overexerting themselves, or injury from snow sliding on top of them.

I can’t make recommendations on when to remove snow from any particular roof. It is up to the individual building owner to consider the benefits and dangers of snow removal and determine their own course of action. If your structure is in question, it is always best to consult a registered professional engineer.

Dear Guru: Can I Get Snow Breaks From You?

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: I put gutters and downspouts on my barn this summer and now am dealing with ice sheets damming up against the gutter, and am concerned that the ice/snow backing up may bend the gutter or worse rip the gutter off the fascia. Can you tell me the solution? I see some metal roofs with plastic/metal/??? strips or triangular pieces at the lower end of the roofing sheets, and I assume these are ice breaks of some sort. Can I get these things locally, can I get them ordered through you, or through ABC Steel? How do they work, how are they attached, and do they compromise the roof water shedding? NOT ONLY IN OHIO

DEAR ONLY: 22 years ago I moved into my current home. It has a 7/12 roof slope and a steel roof. Sliding snow ripped the gutters off the very first winter, so I learned the hard way.

Snow breaks – we can provide steel snow breaks for your building (the steel company sells only wholesale, not direct to the public). They are pieces of steel trim, which attach to the roof steel with stitch screws at every high rib. On a building such as yours, we’d suggest going with two runs on each side – one at the first purlin line up from the eave and another 1/2 way up the roof. In your case this would total 14 pieces 10’6″ in length and 400 stitch screws. This product will not impede water running off your roof.

DEAR POLE BARN GURU: Trying to evade having my taxes doubled. Main goal…I want living space on top for underachieved kids. How about totally open bottom area garage doors on both ends. Or just a car port. Simple open living area on top. A small bath, two small bedrooms, open kitchen open living area. If it’s over 800sq. ft. taxes double. Any ideas on a plan and cost? KERRY IN PONTIAC

DEAR KERRY: As you did not leave an email address or any other way to contact you, we’d have to work in broad generalities. I would encourage you to discuss your desires with one of the expert Building Designers at Hansen Pole Buildings.

 I’ve never been a huge fan of design based upon evading taxes, etc. It won’t matter how much you are able to save in taxes, if your new building does not meet with your needs.

 Your lower area could be just an open carport, basically supporting the living space on stilts. This is very popular in the south where low lying lands are frequently flooded due to hurricanes.

 As we do not design for non-structural interior walls, you would have the total flexibility to place rooms as you best see fit. Your overall size limitation would allow you to do something like 20’x40’, 24’x33’, 26’x30’ or 28’ square. I’d suggest you play around some with possible room sizes….and give us a call at your earliest convenience.  99% of the time you will get a price while you are on the phone with a Building Designer.