If you're a shopping center owner or manager, you certainly spend less time on the roof of your center than you do on the floor that gets constantly worn down by the droves of customers visiting your tenants.

But, just as "under all is the land," in real estate, it is equally true that "over all is the roof" in the shopping center industry. And there's a lot of stuff that can go wrong up there without you having a clue - until you have to pay to fix a bad leak or, worse still, replace the whole roof and blow out your capital improvements budget in the process.

Haven't checked up there in a while? Maybe a little nervous about what you might find? Or maybe you need a new roof and don't know your TPOs from your EPDMs? Don't worry - read on and listen to what a number of roofing industry pros have to tell you about roofing products, the value of maintenance, and how to figure out whom to do business with.

Want to be a guinea pig? As all retail building owners and managers eventually learn (some the hard way), a roof is not a roof is not a roof. "In buying a new roof, keep in mind that you are buying the manufacturing process," advises Thomas J. Bradford, vice president of Bradford Roof Management and Bradford Roofing and Insulation Co., roof consulting and contracting companies based in Billings, Mont.

"There will always be new products in the roofing industry," notes Bradford, and "The question to ask yourself is whether you want to be the guinea pig." When selecting a roof, "choose only from roofing systems that have a proven track record in your part of the country - and be somewhat wary of [those with] the low price."

Materials and membranes There's a lot to choose from out there these days. "As far as trends in materials go, it seems that there is a new product every day," according to William D. Sanders, vice president of Richmond-based Roofing Consultants of Virginia Inc.

The most widely accepted new products Sanders has seen recently include TPO (thermoplastic olefin or polyolefin) roofing membranes and cold-applied BUR (built-up roofing) systems. "However, we have also seen a large number of building owners going back to time-tested roof systems such as a four-ply asphalt built-up system," he notes, "or the single-ply EPDM (ethylene propylene diene monomer) that has a proven track record of performance."

"Over the past five years, the roofing industry has been moving toward heat-welded thermoplastics," says Ray Maczik, director of marketing communications for Saginaw, Mich.-based Duro-Last Roofing Inc., a manufacturer of a prefabricated, reinforced thermoplastic single-ply roofing system for commercial and industrial (flat or low-slope) buildings. "The ease of installation and the reduction of liability are the main reasons for this shift," he notes.

"The fastest-growing membrane type in the commercial/industrial roofing industry, as well as the new construction retail industry, has been thermoplastic plastic membranes (PVC & TPO single-plies), according to John J. Cambruzzi, manager, Preferred Accounts, for Denver-based Johns Manville Roofing Systems, a manufacturer of commercial and industrial roofing systems, including Built-up, Modified Bitumen (SBS and APP), and Single-Ply (PVC, TPO and EPDM).

PVC membranes have steadily gained in popularity because of their proven track record and their ease of installation, notes Cambruzzi, while single-ply membranes can be installed efficiently and cleanly.

TPOs on top? Meanwhile, "TPOs have recently become more popular as well," says Cambruzzi. But, "I recommend that building owners proceed with caution when considering the use of a TPO membrane. They are relatively new in the marketplace and most likely the formulation of current products differs from those produced in the past few years - and these formulations may also change in the future as well."

"We have seen a tremendous increase in the popularity of TPOs during the last five years," reports Tom Gallivan, marketing manager for Stevens Roofing Systems, a Holyoke, Mass.-based manufacturer of TPO roofing membranes sold under the Stevens EP brand name. One of this company's bigger recent projects was the roof of the Great Mall of the Great Plains in Kansas City, he reports, "a 1 million sq. ft. new construction job utilizing White Stevens EP (R).

Several factors are at work behind the rising profile of TPOs, notes Gallivan. "Part of the reason for increased demand is due to an increasing awar eness in the industry of the inherent performance characteristics that TPO technology brings to the industry as compared to other common but older technology roofing systems," he says. "For example, TPOs have the weathering and cold temperature flexibility of EPDM systems with the heat-welded seam capability and integrity of PVC systems - without the drawbacks of either."

Additionally, "Specifiers and architects are better-educated about the role reflective roofing plays in energy efficiency," according to Gallivan, "and the end result is that we have seen our reflective TPO being specifically written into specs."

Maintenance is crucial No matter what type of roofing you choose, you have to take care of it to get the most out of your investment. Most retailers and property managers don't even come close to paying enough attention to maintenance.

"It is amazing the amount of premature replacement of roofs that takes place," says Sanders. "The design life of any basic commercial roofing system is 20 years," he says, "but the national average [actual life of a commercial roof] is actually anywhere from seven to 10 years."

The cause of this discrepancy doesn't lie with the roofs themselves, according to Sanders. "I don't think you are looking at materials failure as much as you are a lack of maintenance," he says. "For the most part, roof maintenance is something that is totally ignored until someone starts to complain about leaks."

And , at that point, it is normally too late for maintenance. Instead, it's time for either costly repairs or even replacement, according to Sanders.

As he points out, "99% of the time, leaks start out as small, insignificant defects - but by the time they show up inside a building, they can present huge problems. They can grow through expansion-contraction caused by alternating freezes and thaws, and you can wind up with a lot of wet insulation, deck damage and many other things - well before you may ever realize you have a problem."

Owners/managers are not entirely to blame for ignoring the importance of maintenance. In addition to having to deal with a wealth of other issues, they also typically don't get a lot of encouragement and/or advice in this area from their roofing contractors.

"The typical roofing contractor doesn't make money doing maintenance - they make money by replacing roofs," according to Sanders. "They have a vested interest in getting up there, tearing off the old roof, putting on a new, and walking away and never touching it again until it needs to be replaced."

Problems and solutions In addition to deferred/ignored maintenance, another common reason behind the premature replacement of roofs is the failure of building owners/managers to control access to this part of their facility. This problem is especially apparent in the shopping center world, according to Sanders.

"We had a mall here in Richmond where there was a huge problem with leaks," he recounts. "And the reason for all the leaks was that whoever needed access to the roof for any reason had absolutely free rein to do whatever it was they wanted, and no one checked behind them," says Sanders. "If someone needed to put in a satellite dish, set up a TV antenna, or, especially, install a new AC condenser unit, the mall managers would just let them have at it, with no supervision or coordination - and you can well imagine what that roof wound up looking like."

Mall management finally came to Sander's firm for assistance. "It was very important for them to begin taking a proactive stance when it came to taking care of their roof," he says. "We told them that the first thing they had to do was take control, and make it an iron-clad rule that if there is a penetration of the roof for any reason, certain procedures have to be followed," says Sanders.

These procedures have been incorporated into all work orders involving rooftop work. "We advised them [mall management] to even go so far as to write the name of a roofing contractor into all contracts, which state that whoever penetrates the roof for any reason has to contact that roofing contractor to work out - in detail - how to get the work flashed properly," says Sanders. "The contracts also state, for example, that if an AC unit is removed, all associated curbing also has to be taken out and the space roofed in solid to specifications," he says, "which avoids having a roof where you have tons of abandoned curbs and other stuff left behind."

A lot of roof maintenance "is just having someone walk your roof who is competent, trained, knows what to look for and how to evaluate the need for repairs," says Sanders. "A budget needs to be set up on a yearly or bi-yearly basis for roof inspections and repairs," he notes, adding "this is the way to catch small things before they turn into big problems."

From reactive to proactive Like Sanders' company, Bradford Roof Management also utilizes a combination of knowledgeable roofers and the preparation of budgets in order to help owners/managers take charge and get the most mileage out of their roofing dollars.

"We focus on budgeting for proactive roof maintenance management," says Bradford. "And, in addition to the preparation of long- and intermediate-term budgets, we also offer roof surveys, pre-qualification of contractors, plan and specification preparation, on-site inspection and audits on maintenance work."

Data generated in a roofing survey covers several areas, according to Bradford. These include footprint CAD drawings of each building section along with line-item maintenance requirements by section, prioritized by severity and costs, he notes. "Additionally, historical data is collected to include deck type, the type of insulation present and roof membrane identification," says Bradford.

For budgeting purposes, replacement costs are typically based on the same specifications as those for the existing components of the roof, says Bradford, and reported in today's dollars.

Detailed documentation is important, adds Sanders. "It is important to realize that each roof must be addressed individually due to the numerous types of roof systems that are utilized," he notes. "We recommend that the building owner request a copy of the roof system manufacturer's literature for the in-place roof system in order to have a better understanding of the installed system."

And, at the same time, "The owner should also keep a file that contains all of the historical information for the roof system," says Sanders, "such as a copy of the manufacturer's roof guarantee, a copy of the contract from the original roofing contractor, a roof plan diagram, a roof leak history report as well as copies of all annual inspection reports and corrected maintenance items that have been performed."

It takes some work and some organization on the part of the owner. But it can be worth it. "Basically, what we are doing is helping the owners move from a reactive or 'crisis' style of roof management," says Bradford, "to one that is proactive and enables them to take control of their roofs."

Finding the right company ... Whether you are getting a roof inspected, maintained, fixed or replaced, the all-important first step is the selection of the right roofing contractor, notes Bradford.

"Find a contractor you have faith in, one with a reputation for high-quality workmanship, one familiar with the service and maintenance needs of a wide variety of roofing systems," says Bradford. "There is not one system that is right for every application," he notes, "and a competent contractor will be able to make recommendations as to the best system given your specific situation."

... that's on top of roofing industry trends The right roofer who is up to speed on the latest trends in roofing will save you money, according to James Murton, president of Murton Roofing Corp. The Miami-based company is a part of a national partnership known as TECTA (based on the Latin word for "roof"), comprised of roofing contractors across the country. Murton Roofing recently completed a 1.7 million sq. ft. roofing project at Miami's Dolphin Mall, reports Murton, using a modified bitumen system to produce a 35,000 sq. ft. barrel roof of standing seam metal panels.

"Value engineering is the new trend in roofing," says Murton. In this method of carrying out a roofing project, "to help keep prices within a specific budget, the owner, contractor, architect and subcontractor get together to determine what is the best way to install a product that is both within the budget and meets the necessary performance criteria," he says.

The roofing business is, of course, a component of the overall construction business. And, "the biggest trend in the construction industry - as in all businesses - is the development and use of the World Wide Web," according to Stevens Roofing Systems' Gallivan. "The net is rapidly changing the way we gather, process, and disseminate information, as well as the way that construction projects are designed, bid, sold and completed," he notes. "It is a paradigm shift in the industry that will affect its very core."

Everything's negotiable. But you might want to keep in mind that players in the roofing industry are operating under some price constraints. "It has become more and more difficult to remain profitable in the roofing business," says Johns Manville's Cambruzzi. "Raw material costs have increased substantially in the last several years," he notes, "with the finished products selling for less today than they did 10 years ago."

Picking the right roof When it comes to the type of roof to buy, "the key issues a building owner should address include finding a roofing manager and a roofing system that have proven records of performance," says Duro-Last's Maczik. "A careful evaluation of the roof warranty - for hidden costs and required maintenance over the life of the warranty - is also suggested," he advises.

Another recommendation from Maczik is to take into account how the installation process will affect the environment your business operates in. And as a particularly important consideration for retail buildings, "Can the roof be installed without disrupting the normal, everyday routine of your business?" he asks. "Are there messy materials, hazardous chemicals, and/or noxious fumes inherent to installation that might affect your customers, employees or tenants? Will the new roof be maintenance-free? Leakproof? Energy efficient?" also need to be asked, he says.

Ask a lot of questions, adds Gallivan. Sample questions to ask a TPO manufacturer, which can also apply to makers of other roofing types:

* Do you manufacture the product yourself? ("Many companies are merely marketers of a pre-compounded product and have little technical knowledge," says Gallivan).

* How many years of TPO manufacturing experience do you have? ("Five years is a good minimum.")

* How old is your oldest TPO job?

* How is your product different from others on the market?

* Can your company supply a list of references of installations that are similar? ("Any roofing system's suitability and longevity varies depending on building location and use."

* What are the environmental consequences of tear-off and disposal of a system?

Finally, "I recommend that building owners select a manufacturer that is well-established and has a history of providing quality services and roofing systems," says Cambruzzi. The ability to provide a variety of roofing systems is also important, he notes.

"Building owners should also take into account the environmental conditions, the type of access to the roof during installation, time expected to occupy the building, etc.," he says, "as well as making sure that that the contractor chosen is experienced in installing the type of roof system required."

The following deficient roof conditions are the most common ones to look for when you perform your roof maintenance inspections.

Asphalt or coal tar gravel-surfaced BUR * Interior leak areas

* Low filler at pitch pockets

* Open wall and/or curb flashing laps

* Failed/split gravel stop stripping felts

* Clogged roof drains

* Open expansion joint covers

* Fallen wall or curb flashing

* Roof splits

* Damage from equipment maintenance

* Previous improper repairs

Single-ply membranes * Interior leak areas

* Open seams at walls or curbs

* Failed gravel stop stripping

* Low filler at pitch pockets

* Clogged roof drains

* Open pipe flashing

* Open field seams

* Roof punctures or tears

* Grease or chemical contaminants

Metal roof systems * Interior leak areas

* Deteriorated sealant between roof panels and metal trim

* Missing panel closures at gutters, valleys and ridge areas

* Rusted roof panels or metal trim

* Deteriorated fastener grommets at roof panel and metal trim attachments

* Clogged gutters and/or downspouts

* Lack of crickets at high sides of roof curbs creating water dams

* Roof panel deflections from mechanical or snow loads

Source: William D. Sanders, Roofing Consultants of Virginia Inc., Richmond.