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Building Operating Management

Keeping Tabs on Roofs

Out of sight and out of mind, the roof may be in trouble

September 2004 - Roofing   Article Use Policy

A report prepared on behalf of the Roof Consultants Institute


From careless HVAC technicians to tricky warranties, roof problems can spring from myriad sources, and there’s no single solution that guarantees the roof will survive these trouble spots. However, keeping a careful eye on the roof and not letting small problems fester into big ones are important steps toward long roof life.

Scheduled roof inspections and maintenance are the best ways to avoid the most common roofing problems that facilities executives face, say roofing experts. Roofs should be inspected at least twice a year, in the spring and fall. They should be looked over again after contractors work on the roof or after a hurricane, hail storm, lightning strike or ice storm.

“Routine maintenance is a good investment,” says Luther Mock, president of the Roof Consultants Institute (RCI), an association of professional roof consultants, architects and engineers who specialize in roof systems. “It can prolong the life of the roof.”

Water Hazards

The most common roof problem is a leak. Routine maintenance and inspections help ensure the roof is able to protect the building against its main antagonist: water.

“Water is a universal solvent,” Mock says. “It will damage anything, given time. If you can keep water off the roof, you will get more service life out of your roof covering.”

Something as simple as clearing drains can prevent a plethora of problems because the roof dries faster. Unfortunately, starting a maintenance plan now might prevent future problems, but it won’t vanquish existing problems.

If the roof has been leaking for some time, the structural integrity of the roofing system could already be damaged and its load capacity compromised, says Mock. This is a special concern for some roof decking materials, such as cementious wood fiber, which are more vulnerable to water damage than others.

Equally serious is wet insulation. “Insulation must be dry to do its job,” Mock said. “If it’s not doing its job, the building manager or occupants will end up paying more for energy costs.”

To detect wet insulation, a roofing expert will conduct a non-destructive survey with infrared thermography, capacitance or nuclear test method options. Wet insulation warmed during the day will hold heat after sunset. An infrared scan pinpoints where heat radiates from the insulation.

Wet insulation is not an insulation failure; it’s a roof system failure. Membrane holes are perhaps the most common source of these malfunctions. Holes can be caused by foot traffic, weather and faulty construction, to name a few.

Outside of the roofing system itself, HVAC units are perhaps the biggest culprit of roof-related problems. Repairs on HVAC systems can wreak havoc on roofing systems, particularly if support frames aren’t high enough to permit access beneath the unit for maintenance. An HVAC technician can damage a roof membrane by struggling to reach under the unit or by carelessly tossing tools and equipment around, says Gary Cattel, second vice president of RCI and president of Roof Engineering.

Tracing Damage

One way to reduce carelessness is to inspect and document the roof condition prior to the repairs, then demand that the HVAC company pay for damages contractors cause. It is recommended that the facility executive maintain a sign-in sheet to document all rooftop activity.

“HVAC techs can sometimes damage the roof system and not tell anyone,” says Thomas Hutchinson, a principal at Hutchinson Design Group and first vice president of RCI. “Let them know that you’re watching. It usually takes only once or twice.”

Ironically, routine maintenance on HVAC systems is important to the integrity of the roofing system. Clogged condensation drains, broken sealants and dirty filters can allow leaks, even on sunny days, says John Willers, RCI secretary and owner of Rooftop Systems Engineers.

Curbs around HVAC units also can cause headaches. Many times curbs are cut into roof decking as an afterthought rather than set in place during construction. This can result in improperly fitted curbs and insulation turned into the curb, Mock says.

The height of the curb can be a problem, too. While the International Building Code requires curbs to be at least 8 inches, 10- to 12-inch curbs are better, Cattel says.

Coordinating the design of the roofing system with the design of the HVAC system can prevent common roof problems.

“If HVAC equipment is going to be integrated into the roof system, the designer must coordinate with the HVAC engineer,” says Hutchinson. “The HVAC person may not be familiar with the roof system and vice versa.”

Hutchinson says that curbs, piping, condensation lines, gas lines, electrical and other details should be accurately laid out on the roofing mechanicals. Likewise, structural details of roof and deck should be included in the drawings for every element integrated with the roofing system.

When a Leak Occurs

If the roof starts to leak, the first priority is to stop the leak.

“Put a cork in it,” Willers says. “Don’t worry about compatible materials. There isn’t time to wait for a contractor to come out with the appropriate materials.”

If the roof is under warranty, follow the reporting protocol outlined in the warranty, which usually means the contractor is notified and can make repairs, normally within 48 hours. “A lot of contracts require timely reporting, and that’s the owner’s responsibility,” says Cattel. “If they don’t call within a given period, the warrantor may attempt to decline coverage.”

Hutchinson adds that it’s still a good idea to contact the manufacturer or warranty holder directly, regardless of protocol. If the problem stems from the contractor’s workmanship, the problem might not be recorded properly.

It’s equally wise to contact the project’s roof consultant. Cattel says a leak should be watched closely. “The worst thing you can do is let it fester.”

Facility executives with buildings of different roof types must keep good records of what warranties cover which roofs and who to call for each. File all warranties in one spot and keep track of roofs with expired warranties and roofs that never had warranties, Mock says.

Pinpointing Problems

It’s equally important to develop a relationship with a contractor who has experience in all types of roofing systems. “A one-trick roofer might get you through a crisis, but the repair most likely will not be long-term,” Mock says. If the building is old or if it is the victim of poor record keeping, it might be difficult to determine the exact roof type, experts say. That’s another reason to look for a contractor who can handle an array of roofing systems.

Once the crisis stage is past, it’s time to investigate the source of the problem. Looking around membrane penetrations, examining the flashing at high walls, and searching for slips at edge details and tears in the membrane are the most important steps in the investigative process. Inspect sealants as well, and check to see whether exhaust caps are properly installed.

“You really have to investigate to see what kind of condition those things are in,” Mock says.

To get an idea of how well membrane seams are performing, tug on them. If the seams are tight, it means they’re performing well. If they’re deteriorating and loose, it could indicate they were not installed properly in the first place.

On asphalt roofs, look for dried out or defective pitch pockets and open joints or splits. If there is a blister in the asphalt, don’t step on it to release the pressure, Mock says. “If the blister is holding pressure, that means water can’t get in.”

The blister should rise and fall with temperature. Mark the blister with spray paint and monitor it as part of the roof’s routine maintenance. If the blister fails to rise on a hot day, then it needs to be repaired.

If a problem isn’t readily apparent, water testing can recreate the leak so it can be traced to the source.

“When it’s raining, you can’t always localize the source because the whole exterior is wet,” Willers says. “We go out on a sunny day and make the roof leak by applying water to suspected areas.”

The amount of work required to stop a leak depends on the complexity of the problem. If a seam is the problem, the solution is merely to repair it instead of re-roofing the entire building. A tear in the membrane might require a simple patch.
Complex problems should be reviewed based on whether the proposed solution is short- or long-term.

“The worst thing a facility executive can do is get bids from contractors with no scope of work defined,” Hutchinson says. “One contractor might bid a short-term repair, and another might bid a permanent solution. When you select a repair based on price, you don’t really know what you’re getting.”

Warranty Work

Before settling on a new roofing system, facilities executives should determine what type of warranty they want, Hutchinson says. For example, a full system warranty offers a single point of contact and covers all the roof system components for a given period of time. Another warranty might focus only on the product’s watertightness, covering only the cost of a patch. A third option might be a basic two-year warranty on workmanship, provided by the contractor.

Whatever warranty is selected, read it immediately, roof consultants say.

“I know they’re boring,” Mock says. “But you need to know what’s included and what’s excluded. Many times, there are exclusions that people wouldn’t think of. For example, to keep the warranty enforced, you have to keep up the maintenance on the roof. It’s the facility executive’s responsibility to maintain the roof to keep the warranty in force.”

While most warranties cover the cost of fixing a leak, few provide coverage for consequential damage. This means that soggy carpets and ruined office equipment won’t be replaced under the roof warranty. Even damaged insulation is excluded.

“The spirit of most warranties says that if there’s a leak, they’ll fix it. Any related damage traditionally falls under property or renter’s insurance,” Mock says. “Know the exclusions. That’s very important.”

Other common exclusions include damage from condensation, roof traffic, hail, wind in excess of certain speeds, and mold and mildew.

Some warranties might include an unpleasant surprise. A building owner might think the roofing system carries a 20-year warranty. If the roof was installed incorrectly, however, the warranty is void, says Patrick Downey, executive director of Keystone Building Construction and RCI treasurer.

Facilities executives should understand the terms of replacement and what portion of the warranty is covered by the manufacturer and what portion is covered by the contractors.

Some warranties provide no dollar limit on replacement while others are prorated based on how long the roof has been installed. A prorated warranty will cover fewer repair or replacement costs for a system nearing the end of its life than for a newer one.

Other nuances include clauses requiring facilities executives to inform manufacturers or contractors when any work takes place on the roof, including work on other building elements. For example, if a new air conditioner is installed, manufacturers or contractors might have a say in the installation process.

“If you have a warranty, you can’t do whatever you want to do to the roof,” Mock says.

Facilities executives can ensure that the roof and warranty meet the necessary conditions by having the warranty holder inspect the completed project before accepting the warranty.

“Have a manufacturer’s rep come out during the course of work and walk the job with him or her. Make sure that materials are installed properly,” he says.

Experts also suggest that facilities executives develop good relationships with a small number of manufacturers and contractors. “A lot more problems get taken care of through relationships than through the warranties,” Downey adds.

In fact, a warranty may not be in the best interest of the facilities executive.

“You might get better coverage without a warranty,” Downey says. “Have the roof system installed to manufacturer’s specs, but don’t take warranty. Some warranties are just a marketing function, and more often than not, they’re written to limit liability.

“Most warranties only cover the product that was sold,” he says. “They aren’t going to cover sheet metal components, sealants, mechanical equipment, skylights or expansion joint coverings. When a problem comes up, it’s very likely to be a component not covered.”

Tearing Off the Roof

Sometimes, the only way to solve a problem permanently is to tear off the roof and start over. A core cut can be a good way to verify the necessity of such a drastic move. A core cut allows the roof designer to determine how many roof systems are in place, the type of deck and the general condition of the roof system.

“We can often take test cuts to see what caused the problem and design them out of the new roofing system,” Cattel says.

If the old roof must go and a warranty isn’t an issue, the facilities executive first must define the purpose of the new roofing system. Roofs are sometimes used for recreational activities, storage and even helicopter landing pads – many times, uses that were afterthoughts to the original construction.

Climate is another critical consideration. A building in Chicago must withstand snow loads while a building along a coast must withstand gale force winds. Extreme temperature changes and even earthquakes may need to be taken into consideration.

Once purpose and weather hazards are determined, appropriate materials must be selected. The biggest mistake in the design of the roofing system is employing materials with different service lives, Downey says.

“For example, using sheet metal components with a 10- to 15-year life can compromise the integrity of a roofing system designed with a 25-year service life,” he says. “Or you could put on a roof with a 10-year service life yet install coping with a 30-year life. Often facilities executives pay a premium for high-end products, but when they have to replace the roof, the high-end components get thrown out.”

Downey suggests that facilities executives specify service life and maintenance requirements up front.

In fact, upfront, detailed planning is key to minimizing problems caused by all roof trouble areas. There’s no cure-all, but like any facet of facilities executives’ jobs, an ounce of prevention is worth a pound of cure.


Roof Consultants Institute: Setting Professionals Apart

The Roof Consultants Institute (RCI) is an international non-profit association of professional roof consultants, architects, and engineers who specialize in the specification and design of roof systems.

Since 1983, RCI members have offered design, repair planning, quality observance, legal testimony and general roof management services. RCI’s roof consultants adhere to an ethics code that offers professional service without affiliation with any product or manufacturer. The Registered Roof Consultant (RRC) and Registered Roof Observer (RRO) programs distinguish professionals with established standards of education, experience and ethics.

The Institute’s current membership numbers more than 1,800, including professional, industry and facility manager members. RCI boasts an international constituency residing in all 50 states, Canada, Mexico, Africa, Europe, Australia, the Middle East and the Philippines.

“The practice of roof consulting is relatively new,” says Patrick Downey, RCI treasurer. “It is a blend of what you look at in an engineer, an architect and a contractor. Typically, the roof is the source of the greatest cost and greatest problems. Most facilities executives don’t have the necessary in-house expertise. The role of the roof consultant is to provide that expertise.”

For more information about the Roof Consultants Institute, call 1-800-828-1902.

 




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