Tag Archives: How ice dams form

Roof Ice Dam (Sid the Snowflake)

The Adventures of Sid the Snowflake (Trapped Behind an Ice Dam)

Sid tumbled through the sky at the mercy of the wind. One gust sent him hurling back up towards the gray mist that he’d just departed from, then another would suddenly spin him in a different direction. He tried to catch a glimpse of the ground below as he careened through the stormy heavens, but all he could see was a sky full of his fellow snowflakes, all in the same predicament. Not knowing whether he was going to land in the ocean, on solid ground, or on the backside of a cow, Sid was filled with the angst of an uncertain future.

A voice suddenly broke his reflective solitude.

“I’ll see you on the ground!” another snowflake yelled to him, seemingly enjoying his carefree flight.

“Alright,” Sid responded as he glided closer and closer to earth. “Good luck!”

Illustration of Sid the snowflake

Sid knew the chance of seeing this new acquaintance again was slim. Snowflakes that begin their decent together often ended up miles apart by the time they reach the ground. Still, Sid took some comfort in the friendly words and embraced a small sense of reassurance offered by the stranger. Sid was just one of millions who were facing the uncertainty of an unknown destination. This was all part of their cycle of life.

The gusty winds subsided during Sid’s descent, and as visibility increased he could make out forms on the approaching ground. Sid’s last journey took him on an exciting adventure in the North Pacific Ocean, and he was half expecting the same. During that adventure, he enjoyed seeing a wide variety of exotic marine life, and he even had the experience of rolling across the back of a small humpback whale.

But today would be much, much different. There was land below. Not only was there land, there were people! Sid was headed for a city. He had fallen into a small town once before, and though the experience wasn’t horrible, it was far from being his favorite. Being scooped up in a shovel and tossed aside to be splattered by dirty, ill-mannered slush from passing cars was something he really hoped he wouldn’t have to endure again.

As he drifted toward the ground, Sid could see that many of his peers had arrived earlier, blanketing the uneven ground and buildings with a pristine layer of white. He plotted his landing and prepared for his arrival in the front yard of a small farm house. But a sudden gust tossed him aside and onto the roof of the house. He breathed a sigh of relief, grateful to be on a roof and not in some cow pasture. He was quickly joined by others, and the group settled in, not yet sure of their fate.

After five uneventful days on the roof, Sid started feeling a bit “loosey goosey” as warm air that had escaped from the attic warmed the roof and tickled his rear end. He watched as friends around him collapsed from their frozen state into clear liquid, each letting out a loud “whoo hoo” as they tumbled down the roof valley. They zigzagged their way down the giant water slide before crashing into a growing pool that had formed behind a mountain of snow and ice at the roof’s edge.

Then it was Sid’s turn. As his last frozen foothold gave way, he cascaded toward his friends, clumsily bumping into a few stubborn packs of ice before being released into the small pool. This would be Sid’s new home for a few days. The large ice dam wasn’t going to allow any of them to drip into the gutter or downspout anytime in the near future.

Illustration showing how roof ice dams form

Apparently, the ice dam had been growing long before Sid’s arrival. The shingles were much warmer higher up on the roof, but the surface near the roof’s edge was still cold. When drops of melted snow trickled down into the freezing valley below, they collected and transformed back into their frozen state. Without the warmth escaping from the attic as it did near the top of the roof, the frozen water would remain where it was, completely at the mercy of Mother Nature. Here it would dwell until the temperature dictated otherwise.

The process of melting and refreezing behind the formidable ice dam had repeated several times before Sid had arrived. And now, trapped behind the ice, Sid and his friends would also take part in that process. As night fell on another cold day, Sid and his companions once again changed back into their frozen state. They could do nothing but wait for warmer weather.

With each passing day, the crowd grew larger as runoff from warm areas of the roof increased the pool’s size. Milling about like restless concert goers awaiting the opening act, some of Sid’s cohorts grew impatient.

“Let’s work our way through this place and drip inside the house,” he heard one say. Soon, a plan was hatched, and an ample collection of supporters began their unconventional trek. In their liquid state, aided by gravity, they wound their way down through a maze of cracks in the roof. If a crack came to an end or became too small, they would wait patiently for the freezing temperature to grant them their super powers. As they transformed into ice, they expanded with tremendous force, enlarging the existing cracks and preparing a way for them to continue their journey when they resumed their watery ways. With each night and freezing day, the group inched its way through the aging roof. Before long, a trail had been blazed, creating a small stream for others to follow. It didn’t take long for one of the home’s walls to absorb a budding contingent of melted snowflakes.

But Sid had no intention of sliding down into the house. The idea of seeping into a home seemed unnatural. Besides, he hated the taste of plaster and drywall, and the last thing he wanted was to become a filament of mildew or mold on a gross, stained wall. He didn’t mind waiting with the others behind the ice dam. Unfortunately, the homeowner hadn’t installed a roof deicing system, which would have prevented Sid’s derelict friends from turning in to a bunch of drips to forge an alternate path into the house. Eventually however, the temperature would warm and melt the ice dam, allowing Sid continue on his way. He’d made this journey once before, resting on a Utah rooftop for over a week before finding his way back to a stream, and eventually back in to the clouds – where he was happiest.

At the end of another day, Sid looked up to the stars that shimmered through the wisps of clouds drifting in the moonlight. “Someday,” he reflected, “I’ll be back up there.” The ice dam couldn’t hold Sid forever, and he knew it. He closed his eyes and promised himself, “Tomorrow, I’ll find a way to start my journey back up to the sky.”