Unexpected Danger: Winter Weather’s Stress on Roofing
Winter weather takes its toll in a lot of ways: on roads, cars, and the bread and milk aisles of the grocery store. Winter storms, however, also endanger roofs at both homes and office buildings, a crucial topic which people often only learn about after it’s too late.
The catastrophic effects of snow and ice have the potential to cave in a roof or leak water down the inside of the walls, causing massive internal damage. What could be worse than a roof collapse during a blizzard?
Ice damming and roof snow load are the two most common causes of roof damage. Both are dangerous and both can occur from moderate winter precipitation as well as from record setting blizzards.
Ice damming is the term used to describe a phenomenon in which barricades of ice form along edges of roofs, preventing melted snow from draining properly. Instead the melted snow seeps through the roof. This has the possibility to damage the ceilings, walls and insulation, while also creating an environment conducive to mold growth. Large icicles, although beautiful, are one sign of a forming ice dam.
A major cause of ice dams is heat permeating through the roof, due to faulty insulation, which melts snow at a faster rate than the ice blocking the drains. Since the drains are still blocked, it leaves the snow nowhere to go but through the roof itself. Another factor in ice dams are gutters that aren’t cleaned out before the snowfall, which causes them to become plugged sooner.
“Just the other day we were at two homes in Lititz and they had water flowing down the inside of the walls because the backup,” Owner of Weaver Construction and Roofing, Randy Weaver said.
The Weaver team offers preventative solutions to eliminate ice dams. Adding ice and water shields under the roof itself, which are designed to block the flow of melted material, is an option, but it is one better applied during the construction of a new roof rather than to a preexisting one. Electrical heating cables can be installed in problem areas to melt ice; they are most frequently added to gutters. A simple but effective solution is to add more insulation to ensure the house retains as much heat as possible.
By the time the snowfall begins, Weaver notes, you are too late. Many homeowners or business owners notice the formation of an ice dam and panic, attempting to clear it themselves. Clearing an ice dam is something better left to a professional.
“If you’re inexperienced and thinking of going up there, you have to consider if you can safely get on your roof and if you’re going to damage the roof if you start hacking,” Randy said. ”That’s why we recommend it is something done by a professional. We see it every year, people panic and do a lot of damage.”
Frequently, homeowners will knock holes in their gutter systems or break loose shingles or tiles, only to realize the damage during the following spring.
Snow load is a term used to explain when the snow laying on a roof becomes heavier than what the roof can support. Snow is heavier than most people realize, especially when wet. Experts report that a foot of snow can range anywhere from 3 lbs to 21 lbs depending on the level of moisture in the snow. That much weight can damage a roof and the structure supporting it.
While a blizzard certainly can place more than a foot of snow on a roof, normal snow conditions coupled with drifting can severely damage an unprotected roof. Pockets of deep snow, that concentrate weight in one area can even be more dangerous than a deep, even snowfall.
“It doesn’t take a heavy snow to create a dangerous situation,” Randy said. “We’ve seen roofs collapse many, many times.”
There are several warning signs that the snow load is exceeding the roof’s capacity. Stress cracks in drywall and ceiling tiles falling are main indications of danger. A loud creaking and groaning sound is another. For commercial properties, a sagging sprinkler system is a warning.
Businesses, which typically have lower sloped roofs are susceptible to the danger of snow load. Additionally, HVAC units which are often located on the roof, can trap snow, which requires careful clearance.
Since the stakes are even higher for commercial properties, as far as cost is concerned, the best bet is practicing proper roof maintenance rather than an emergency response policy. To help with this, the Weaver team offers a bi-annual roof inspection to ensure the health of the roof.
“It is a simple thing but since nobody is paying attention it can turn into a bigger issue. We were on a roof a couple of years ago with a crew that did their own maintenance, and we patched over 250 holes in the roof because of how they shoveled it off. That roof was fairly new. It makes you sick in the stomach to think about. That’s an example of why to call the professionals”
The Weaver team utilizes a few techniques that non-professionals wouldn’t know. For example, they leave on an inch of snow to keep from scraping the roof. Their other techniques are a trade secret.
