Life Signs

Conducting life-cycle analyses of current systems can help resuscitate the roof-selection process and lead to smarter choices.

When making decisions about school roofing, installation cost is important. However, only a life-cycle-cost analysis gives you the total picture.

Many so-called "bargain" roofs last only a decade or so, and if a school needs to be reroofed every 10 years, then the cost over 30 years ends up being more than three times the initial price paid. A quality roofing system should last 25 years or more, so its cost would be much less than the cost of an inferior roof, even if the initial installed cost is more.

Most roofing problems occur in the first few years of a roof's life, and primarily are due to errors in installation. If a roof survives this initial phase, then the long-term outlook improves.

Since the value of a roof increases if it survives the first few years without incident, there is some motivation for finding out what it means to manage a roof as an asset. This gives insight into the power of using a database in conjunction with life-cycle analysis to manage roofing assets. As a discipline, roof asset management is closely connected to life-cycle costing-both depend upon actual historical databases for roofing projects.

Creating a database Most school districts have enough buildings to develop a sizable database of roofing life cycles. The district should begin by detailing its knowledge of existing roofing systems. Determine when they were installed and what the maintenance costs have been over the years. The database will grow quickly once a regular inspection and maintenance program is implemented.

Some roofing systems last a long time; therefore it can be difficult to sustain maintenance records. Personnel changes, shifting administrative goals and misinformation about roofing trends can become obstacles to life-cycle data collection, especially in the absence of long-range planning. The creation of a database to track this information will make it easier for future recordkeeping. In addition, this building-specific data can be valuable when discerning the problems peculiar to a particular facility.

Measuring quality Roof asset management requires roofing specifiers to quantify investigations and recommendations. Describing a roof as a financial asset requires technical expertise and historical data to assign a value to a roofing system. Value is a measure of quality. It does not matter whether the value is estimated in dollars or as a relative worth compared to some reference or idealization.

Benchmarking or best practices give a baseline to compare roofing systems. Different roofing systems can be compared by giving them a dollar value. The dollar value of a roof should not be confused with the installed cost of the roof.

Using life-cycle analysis as a measure for quality, roof asset management helps isolate factors that contribute to better roofs and sorts out the best practices from many available options. It is a tool for the technical evaluation of roofs.

Refining specifications For a school district, the lessons learned from observations can provide guidelines for selecting the best roof for a given building in a given climate. Roofing materials take the brunt of the effects of weather. Different specifications are needed in different climates. Some roofs work fine in one area of the country and perform poorly in another. Therefore, compare the performance of roofs in different climates.

Another area to be aware of is the effect of insulation thickness on a roof's life cycle. With insulation between the interior of a building and the roofing membrane, the roof does not benefit from the temperature stability of the building interior. It is subjected to various extremes of temperature cycling depending on the climate.

As in any industry, quality must be based upon measurable attributes via statistics. For a roofing system, there are many factors to measure, including installation cost, time before maintenance is required, frequency of maintenance, cost of monitoring, cost of failure, cost of tear-off, cost of re-roofing (labor and materials), value of warranty vs. time, etc. Of course, the simplest scenario applies to a low-maintenance roof that is installed once and needs no repairs for many decades.

The truth about warranties Warranties can be an asset to a school and an important part of a roof asset-management program. However, warranties also can be misleading and promote a false sense of security. It is important to review the warranty to ensure that it is issued with good intent and the manufacturer has sufficient financial resources to back it up.

A warranty is more valuable if it is properly managed from the day the roof installation begins. Inspection and certification of the quality of the installation, specifications and materials are a prerequisite to the issuance of a warranty.

Like most things, a roofing system has a characteristic lifetime. The average life of one roof in one climate is a statistical device for summarizing data available about many roofs. There are several ways to summarize such data. By simply marking down the installation and tear-off dates, theaverage lifetime for a group of similar roofs can be computed after many years of experience. The analysis can be carried to a deeper level by also taking into account such things as maintenance costs.

A profound knowledge of roofing is required to guide a school district into making the right roofing decisions. In some cases, facilities managers have personal preferences. However, if the facilities manager does not have fact-based experience, he or she should defer to an unbiased professional who offers the best solution-and has the facts to back up the decision.

Spencer is manager of marketing and technical services for AlliedSignal, Commercial Roofing Systems, Cary, N.C.

Properly designed and installed, a roof system has predictable maintenance requirements and service life. To effectively maintain your roofs, a roof asset-management program should be created that contains the following key components:

-A roof plan. The first step is to develop an accurate roof plan, drawing the roof to scale with all penetrations shown. At the time of the survey, note deficiencies, either on the same plan or a separate one. The roof plan, which is best developed using a computer-aided drafting (CAD) system, should have a grid for location identification as well as multiple layers to record the physical characteristics of the roof, the deficiencies, the mechanical equipment, electrical conduits and communications wiring, and any other equipment.

If you don't already know, verify the composition of the roof system in place. This is best done by performing a roof cut to identify the roof membrane, insulation and roof deck type. The drainage patterns on the roof should be recorded so you will know if positive drainage exists and to what extent.

-An evaluation of required maintenance. The next step is to evaluate the maintenance required and projected life of each roof level for every building. This will help determine what maintenance is needed, allowing the school to review maintenance and repair budgets and determine if they are adequate. If funds are insufficient, replacement projects may be revisited to determine if it is feasible to extend the service life of a given roof.

By anticipating these requirements, a district can budget funds required to maintain or replace its roof systems. This approach to asset management offers benefits in reduced loss of use, damage to property and disruption of the normal operations of the facilities, all of which result in higher operating costs.

There are software programs available to help accomplish the preceding goals. It is important to select a program that will provide useful information that is easy to maintain. A custom-designed roof asset-management program also can be developed using computer-aided design software and spreadsheet software.

There are two important considerations to keep in mind:

-The implementation of the program and surveying of facilities. This should be done by a qualified roof consulting firm with experience in implementing roof asset-management programs.

-That the value of the roof asset-management program is not in the initial investment. The true benefits lie in developing an ongoing record that can be used for maintenance planning and budget development. The institution must be committed to maintaining the data and upgrading the information on a regular basis.

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