Focus on the Roof

One of the most difficult problems facility executives face is getting the most out of their facility’s roofs. Many roofs have to be replaced before they reach their rated service live.

Why all the trouble with roofs? Part of it is attributable to the environment in which roofs must function. They are exposed to wind, rain, hail, sunshine, as well as birds and other animals. They must withstand temperature swings from well below freezing to in excess of 120 degrees. They serve as a platform for building mechanical systems that can vibrate, inducing stress failures in roofing components. And they must survive foot traffic.

With the strain that roofs are routinely exposed to, combined with the expense of roof replacement, it is logical to think that roofs would be a focus of attention for facility executives. In some facilities they are. Executives at these facilities have found that by following a comprehensive program for managing roof assets, they can lower life-cycle costs for roofs while reducing the frequency of leaks and emergency repairs.

But not all roofs are managed. Less than half of building owners ever file a claim against their roof’s warranty even though most roofs experience some problems during the warranty period. And many of those who do file a claim have it voided because they have not been doing the tasks necessary to maintain the warranty.

The difference between these two groups is how they view the roof. The group of facility executives that are successful in lowering roof costs views the roof as an asset to be managed. The others view the roof as a maintenance expense, focusing on replacing rather than managing.

Roof asset management is a process. It begins with a thorough understanding of the roof inventory that is installed in the facility. The condition of each roof in the inventory is then assessed. Data from the inventory and the assessment is collected and stored in a central location where it can be accessed easily. Evaluation of that data along with data from subsequent inspections is used to develop a schedule and budget for major roof repairs and replacements.

Two Types of Maintenance

There are two types of maintenance programs: break-down maintenance and scheduled maintenance.

The term break-down maintenance is used in the mechanical equipment business to mean repairs made only when a unit breaks down rather than on a schedule. Break-down maintenance in roofing means merely fixing leaks when they occur rather than having an active preventive maintenance program. Roof leaks usually have secondary effects such as causing wet insulation, corrosion, interior damage and perhaps mold.

Scheduled maintenance and repairs can be planned for the owner’s convenience. The owner’s convenience may mean scheduling for optimum seasonal work, plant shutdowns, weekends or school holidays to avoid disruption. Having a regularly scheduled program for repair and maintenance work can also reduce costs because contractors are able to depend on a certain volume of work and staff accordingly. 

How Freezing Temperatures Can Cause Roof Leaks...Even in Florida!

Did you know that Florida freezes can cause your roof to leak? That’s right, many building owners and managers are unaware of the dangers a freeze can have on your roof. Let’s take a look at what water does when it freezes and how it creates a roof leak.

When moisture is on your roof, whether through rain, dew, ponding water or HVAC discharge, it tends to pond in areas. For instance, rain ponding on a poorly maintained pitch pocket. Most liquids have a quite simple behavior when they are cooled (at a fixed pressure): they shrink. The liquids contract as it is cooled; because the molecules are moving slower they are less able to overcome the attractive intermolecular forces drawing them closer to each other. Then the freezing temperature is reached, and the substance solidifies which causes it to contract some more because crystalline solids are usually tightly packed.

Water is one of the few exceptions to this behavior, which is a problem to your roof. When liquid water is cooled, it contracts like one would expect until a temperature of approximately 4 degrees Celsius (39.2 degrees Fahrenheit) is reached. After that, it expands slightly until it reaches the freezing point of 0 degrees Celsius (32 degrees Fahrenheit), and then when it freezes it expands by approximately 9%, which herein lies the problem to your roof.

All the moisture that was trapped in the little cracks and voids in the roof and flashing will expand and make them much worse. Over the course of several freezes, these thermal ‘shock cycles’ create openings and cracks for water intrusion under the membrane, into the roof system, ultimately resulting in a roof leak.

How can you prevent this from occurring? There are two important steps. First, we need to make sure moisture is getting off of the roofing system. This means ensuring proper drainage, no areas or flashings that can hold water and confirming that all HVAC units have condensation lines that run to the drainage ports and are fully connected. Second, we have to make sure all voids, cracks and damage to the roof is addressed and sealed accordingly. This includes pitch pockets, membrane voids, counter flashing sealants, etc.

With a few proper precautions and actions steps, we can ensure that your roof is protected when those night temperatures begin to drop below freezing, or better as you learned, 39.2 degrees.

Don’t Wait ‘Til It’s Too Late!

Most maintenance and engineering managers face the quandary of too many problem roofs for the money available. The problem might well be a lack of money, but it could also be the lack of a coherent roof management plan.

Most managers in commercial and institutional facilities agree that regular inspections are an essential part of a roof asset management program. They also recognize and agree with the basic roof management tenet that regular inspections and routine maintenance reduce ownership costs, reduce leak frequency and severity, extend roof life, and reduce management inefficiencies.

But, in practice, by the time many organizations think about starting a roof management plan, they need a roof-replacement program. The obligation to fund and implement roof replacements has supplanted the opportunities to maintain and repair. If organizations can extend the life of each built-up roof under management one year, they break even on the roof-management plan costs. If they can extend each roof by two or three years, the plan can reduce roof expenditures by a multiple of its costs.

So why don’t all organizations have a viable inspection and maintenance plan for their built-up roofs? Is it inertia or a fear of the unknown? The reasons are hard to fathom, but what is certain is that some plans never get started. Also certain is that even a minimal plan is better than no plan. The best advice for managers is to start now.