​Written By: Bill Scheidegger and Jamie Buenzli

15

WINTER AND YOUR COMMERCIAL ROOF

February, 2019

THE IMPACT OF EXTREME TEMPERATURE, SNOW AND ICE ON A ROOFING SYSTEM
Winter can be a destructive season for any commercial roof.  Fluctuating extreme temperatures, snow, ice and wind can wreak havoc on any roof system.  Flat commercial roofs are constructed with low-slopes and wide spans, making them more susceptible to winter damage.  

EVERY COMMERCIAL ROOF, REGARDLESS OF AGE OR CONDITION SHOULD BE INSPECTED IN THE SPRING TO ASSESS WINTER DAMAGE. 

Proactive preventative roof maintenance in the spring not only minimizes overall roof system costs, it also maximizes the life-span of your roof system and greatly reduces the potential for roof leaks that can cause collateral damage to the valuable assets housed under your roof.  Below are a few examples of what can go wrong on your roof in the wintertime.

​Creating pathways for the water to flow around an ice dam on a roof

ICE DAMS AND PONDING
 
Ice dams are ridges of ice that can build up at the roof edge and prevent snow as it melts from draining off the roof system.  As the water ponds on the roof gravity causes the water to seek the path of least resistance to the ground, which can sometime mean coming through as roof leaks.  Ponding water can also add significant weight and impact the integrity of your roof system. 
 
 
CLOGGED DRAIN STRAINERS
 
Flat roofs are particularly vulnerable to ponding and leaks if the drain strainer becomes clogged.  This can happen in winter because even a minimal amount of environmental debris on the drain in the fall can freeze over winter and create a barrier to the drain.  Environmental debris such as leaves, sticks and seeds can also clog the roof drain as the snow melts and moves the debris scattered around the roof to the drain area.

​Drain strainers clogged with environmental debris causing roof ponding near drain area

THERMAL SHOCK

In Wisconsin, extreme cold in the winter and warm sunshine in the early weeks of spring can cause temperatures to fluctuate by almost 100 degrees in a single day.  These dramatic changes in temperature cause rapid expansion and contraction that can be very stressful to a roof system.  This stress can potentially create splits as well as cause tears and holes in the membrane to expand, increasing the possibility of roof leaks.
​​GLACIATION

Snowpack and ice can form sheets that act like miniature glaciers that move across your roof during melt.  The weight of these glaciers pushing down a roof with higher slope can damage vents and metal stripping which can cause leaks.
    
 
ICICLES
 
Icicles can cause significant damage on multi-level roofs as they fall onto the roof system.  Icicles can puncture the protective membrane on your roof, which can cause leaks if not identified and repaired.

​Winter roof repairs can be very challenging

CHALLENGES TO WINTER LEAK IDENTIFICATION AND REPAIRS

Identifying leaks and making repairs in winter can be challenging.  Cold temperatures and winter precipitation can make roof and ladder conditions unsafe for technicians.  If snow accumulates, shoveling is required to clear the roof in effort to search for the leak cause.  In many cases, ice can inhibit a crew from locating the cause of the leak because shoveling frozen rock or chipping away ice may do more damage to the roof system, therefore every effort should be made to identify and repair potential leaks before winter begins.  
  

​Shoveling snow on a commercial roof to search for the cause of a leak

PREVENTATIVE MAINTENANCE IS THE KEY MINIMIZING WINTER DAMAGE AND LEAKS

Simply stated, your roof system is most vulnerable in the winter months and leak repair can be challenging, if not impossible in the snow and ice.  PREVENTATIVE MAINTENANCE is the key to maximizing roof system performance.  Spring roof inspections are necessary to assess and repair winter damage.  Fall roof inspections prepare your roof for the cold and snow in effort to minimize winter wear.

Call GBR Corporation today at (608) 838-0066 or REQUEST A QUOTE online to learn more about our preventative maintenance and roof asset management programs.