By Phil LaDuke
Published in the November 2011 issue of Today’s Facility Manager
In most areas of the country, the leaves have fallen from the trees, the temperatures have dropped, and people have come to the realization that winter is not too far away. While many people love the winter months, memories of the treacherous weather that affected cities and towns from coast to coast last year can make even the most passionate winter fan a little uneasy.
Cities on the East Coast that typically enjoy moderate winters were inundated with blizzards, ice storms, and snow last year. And those who live in areas with bitter winters and have grown accustomed to asking the question, “How many feet of snow did we get?” were still astounded at the amount of damage the severe winter caused. Much like last year, meteorologists’ predictions include another harsh time for much of the United States, with colder than average temperatures in many regions and above average snowfalls.
Facility managers (fms) who didn’t sustain any roof damage last winter should consider themselves extremely lucky. The Los Angeles Times reported in February 2011 that the brutal winter conditions brought forth an unforeseen benchmark—a record number of roof collapses across the country, including schools, historic buildings, gas stations, malls, and, perhaps most notably, the Metrodome in Minneapolis, MN. By taking a few key steps beforehand, fms won’t have to rely on luck but on the performance of their roofing systems to get them through to spring.
Don’t Skip The Roof Inspection
A roof inspection is one of the most important activities an fm can undertake to prepare a facility for the winter ahead. Whether fms call a professional contractor or venture up to the roof themselves, performing periodic checks on a structure’s roofing system is important. Fms may rely on the theory that if there is nothing leaking on the inside of the building, there is nothing wrong with the outside. This is a dangerous idea to follow.
How many layers are there between the ceiling and the outdoors—ceiling tiles, HVAC, insulation, framing, decking, roofing insulation, roofing membrane, and possibly a garden roof or photovoltaic system? By the time water passes through all the layers and becomes a leak that can actually be seen and/or felt indoors, the damage can be extremely extensive.
Although routine roof maintenance for all low slope commercial roof systems is optimal with seasonal inspections, bi-annual roofing inspections can uncover problems at an early stage, and developing a plan that involves a combination of visual check ups and a professional inspection is ideal.
Do It Yourself?
If fms are only able to conduct a roof inspection once a year, it is best to do so in the fall before inclement weather descends upon the area. It is much less expensive to examine a debris free roof than it is to pay for snow or ice removal in order to conduct an inspection and uncover issues in frigid temperatures.
If the building’s roof has a steep slope, it is best to hire a roofing professional to conduct the inspection. Without the skill and correct equipment, it can become a very dangerous task and a huge liability for fms to undertake the inspection on their own. Even on a flat roof, fms need make sure they are familiar with safety and OSHA requirements before climbing on the roof.
Keep A Checklist Handy
Addressing small scale problems as early as possible can save fms the headaches and expenses of extensive repairs or a complete roof replacement. Fms should look for several basic items when conducting a roof inspection in order to locate signs of wear and the potential for problems:
- Check for surface damage such as holes caused by debris or open seams;
- Ensure drains are clear and flowing, not plugged;
- Make sure pitch pans/pockets are topped off so water can’t get in and freeze;
- Make sure metal or membrane flashings are secured to the walls;
- Make sure coping joints haven’t opened or shifted to expose the wall;
- Check the perimeter of the roof to make sure nothing is loose; and
- Check for anything that seems out of place or loose items that can get blown off and cut the roofing membrane.
A great way for fms who are roofing novices to learn is to hire a trusted roofing professional the first time and follow along during the inspection. By doing this, fms can take notes, see key items to check, and ask questions about how things should or shouldn’t look.
Can’t Hold Everything
Fms may assume concrete decking under the roofing system can provide unfailing strength. Yet, no matter what type of decking the building has, it still has a weight bearing limit. A roof is constructed to carry a “live load” and have a “dead load” threshold. “Dead load” includes the weight of equipment and HVAC that stay on the roof at all times. For example, snowfall is considered “live load,” because it is not permanently situated on the roof.
A building has a maximum volume that it can carry with both loads considered. During heavy snowfall, ice storms, or repeated severe weather events, a structure’s “live load” capacity can be exceeded, causing major damage, roof failure, and worst case, a roof collapse.
To help ensure the roof will last throughout the winter, fms should not assume that melting snow build up will relieve all the pressure on a roof system. Packed snow can remain on the roof for a long time, even if pockets of it begin to dissipate.
If melted snow is draining and the temperature drops significantly, ice blocks can form around drains and cause water backup on the roof along with the weight of the remaining snow. This can become a dangerous cycle, especially if additional precipitation accumulates during that period to add to the “live load” roof burden. It is definitely smart to check the roof after major snow and ice storms, and if there are drastic drops in temperature, after warm periods.
Get The Snow Off
As the roofing industry advances, manufacturers and contractors are offering more warranties and services than ever before. It is becoming increasingly common for roofing professionals to offer weight load checks, snow removal, and ice removal services on a per incident basis.
Some contractors even offer seasonal services. This can entail a crew that can immediately come to a building to remove the burden if snow reaches a certain depth on a roof.
This is a cost effective, preventive measure that can be put in place to protect a building. Paying the cost of snow removal certainly beats replacing a collapsed roof.
LaDuke is the director of quality building services for Indianapolis, IN-based Firestone Building Products.
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