About Marion McKnight

Marion McKnight is vice president of Operations at Houston-based PHP Systems/Design. He has been responsible for overseeing core business and operational functions for more than 20 years.

Six Risks You Should Know Before Putting Skylights on Your Roof

Skylights are popular for a reason. They add an extra dash of beauty to any commercial building, and they’re a great source of free lighting. But there are also drawbacks, and, if you’re not aware of them, the costs can end up being far greater than the benefits. Whether you already have a skylight or are considering adding one to the design of a new roof, make sure you’re prepared to deal with the downsides:

  • 1. Leaks
    Skylights are famous—or maybe that should be infamous—for leaking. Over time, the seals and flashing can deteriorate, providing an opportunity for water to penetrate your roof. Things like rain, snow and debris can accelerate the process. Modern skylights are less prone to leaks than older versions, but even the best skylight can leak if it isn’t installed properly.

    There’s an additional leak risk, too: ice dams. Skylights transfer heat to the surrounding roofing material, causing any accumulated snow to melt. That, in turn, can contribute to ice dams, eventually causing even more leaks and adding to the cost of roof maintenance.

  • 2. Breakage
    Even standard roofs are vulnerable to the elements, particularly wind and storm damage, but skylights are even more so. Hail and flying debris, for in-stance, can easily crack a skylight. And, when it comes to snow loads, skylights can be the weakest part of the roof. If you calculate the maximum weight load based on the rest of the roof, your sky-light could fail from the excess weight of a heavy snowfall.

  • 3. Falls
    For workers performing roof maintenance, skylights pose a risk for serious injury, or even death. Some workers simply assume skylights are designed to bear their weight and will intentionally stand or sit on them. Tripping and falling onto a skylight presents yet another risk. That’s why the Washington, D.C.-based Occupational Safety and Health Administration puts skylights in the same category as other open holes and requires that each one is protected by a screen or guard rail that meets OSHA’s regulations.

    However, guard rails aren’t 100 percent safe either. Depending on the quality of the safety net or the weight of the victim, roof-maintenance professionals can fall through just as easily as they would through a skylight.

  • 4. Light Exposure
    While access to free natural light is one of the primary benefits of skylights, there’s also a drawback. Depending on the placement, skylights can actually let in too much light, contributing to glare and excess UV exposure. Not only can that be hard on employees, it can cause preventable damage to furniture, carpeting, art and more valuable items.

  • 5. Energy Loss
    In stark contrast to the lure of free lighting, skylights can have a significant negative impact on heating and cooling costs. Skylights simply don’t present the same barrier to heat transfer that more traditional roofing materials do. In the winter, heat escapes. In the summer, heat seeps into the building—and sun-light and glare only add to that effect. According to the National Fenestration Rating Council Inc., Greenbelt, Md., skylights can cause a building’s interior temperature to fluctuate by more than half the difference between the exterior temperature.

  • 6. Space Constraints
    Skylights take up rooftop space that could be used for equipment or other purposes. To get the maximum benefit of free natural lighting, you need to dedicate 7 to 10 percent of your roof to skylights. That’s space that can’t be used for things like rooftop equipment and supports. It also claims space that might be needed for workers to perform roof maintenance. And if you have a small roof, that is going to be a problem!

There’s no doubt that skylights contribute to a building’s aesthetic appeal, and they can also reduce the cost of electrical lighting. But they have drawbacks, too, and building managers have to consider both aspects to make an informed decision. When considering skylights as part of your building’s future, remember to think about the hidden costs, like increased roof maintenance, heating and cooling, and safety precautions.

Four Lessons from the Worst Catastrophic Roofing Errors

From dog shaming to funny videos, it seems to be human nature to giggle at other people’s mistakes. But a dog that ate the toddler’s crayons and is now pooping rainbows is one thing. Roof management mistakes can be dangerous, inconvenient and incredibly expensive. Let’s take a look at some of the biggest roofing disasters of the last few years and see what we can learn from them:

1. Risk vs. Reward

When Hurricane Wilma roared into Miami-Dade County, Florida, most people thought the area was prepared. After all, building codes at the time required the ability to withstand winds of 146 mph, significantly faster than Wilma’s highest recorded winds. Imagine a building owner’s surprise when his roof peeled right off the building. As it turned out, the problem wasn’t with the roof itself but with the way it was secured—or wasn’t secured—to the walls. Despite the fact that building codes required a continuous cleat, there wasn’t one in use. In an attempt to save the $3,000 it would have cost to use the continuous cleat, the building owner set himself up to sustain damages of around $400,000. From a roof management risk versus reward perspective, that decision was a really big “oops”.

2. Don’t Cut Corners

A building in North Carolina also lost its roof to high winds. The failure was caused by insufficient anchoring of the roof. During construction, the wood blocking for the roof had been attached directly to the top row of bricks. When the building was reconstructed, the new design called fora bond beam and anchor bolts. Those simple adjustments created a roof that was ready to withstand winds much higher than those that spelled doom for the original roof.

3. Never Run Before You Can Walk

Green roofs are all the rage, and that trend is practically guaranteed to continue for years to come. However, businesses have been incorporating sustainability into their plans so quickly there hasn’t always been time to identify best practices. Sloped green roofs are a good example. The problem with these is a lack of proper drainage and an inadequate growing medium. When those two ingredients are combined with rain or snow, the result can be a load that far exceeds the weight the roof is designed to handle, which can lead to leaks, mudslides and, in the worst cases, roof collapse. For example, in St. Charles, Ill., a green roof collapsed after a heavy snowstorm, causing extensive (and expensive) damage to the facility.

4. Not All Materials Are Equal

During the Big Dig construction project in Boston, a section of ceiling collapsed, killing one person and halting work (and causing traffic backups) for nearly a year. The problem was deemed to be the system of anchors and epoxy used in the construction process. Or, more accurately, the inadequacy of those items. The anchors were shorter than required, and the epoxy used to fasten the anchors to the concrete was below standards. As with the roof damaged by Hurricane Wilma, this is a situation in which shortcuts—in this case, subpar materials—resulted in costs that far exceeded what it would have cost to do the job right from the beginning.

The most striking thing about these catastrophic roof management failures is that the factors that led to them aren’t all that unusual. The losses weren’t the result of inconceivably stupid mistakes that leave the industry asking, “How could that have happened?” What’s striking is that shortcuts like these are far too common. It’s just that, most of the time, nothing happens. The roof never fails, so the shortcuts are never discovered.

However, when something does go wrong, careers are destroyed, businesses and individuals go bankrupt, and lives are lost or ruined. Don’t gamble with shortcuts when it comes to roof management. It’s possible that nothing will ever go wrong. If it does, however, things will never be the same and it’s just not worth it.