Factors To Consider When Purchasing A Roofing System: Part 8 Life-Cycle Costs

Our final installment in this series discusses the life-cycle costs of a roof. Any roof life-cycle discussion must take into consideration the factors covered in previous posts: price; quality; prefabrication; installation disruptions; ease of maintenance; performance; environmental impact. Each type of roofing system will vary on these factors, so it is important to compare your options in order to make the right roofing choice. Some systems are beneficial because they offer substantial energy savings; some are virtually maintenance-free but may cost more to install; others offer lower initial installation costs, but require the expense of tearing off the existing roof and/or regular maintenance once installed.

Clearly, investing in a new roofing system is a major decision that should not be taken lightly. Your choice can determine how long your roof will last, its performance, maintenance, etc. Make sure to research all your roofing options by visiting manufacturers’ web sites and getting their literature or look at independent industry sources – this ensures that you are educated in making the right roofing decision.

Finally, don’t be fooled by lower initial costs. An evaluation of the areas in the following list should help you estimate the real, long-term cost of any roof you are considering.

1. Installation
a. Roof product cost
b. Installation costs (labor & overhead)
c. Tear-off costs (if required)
d. Disposal costs
e. Building disruption costs
2. Long-Term Durability
a. Regular maintenance costs (over 20 years)
b. Roof replacement costs, if life expectancy is less than 20 years
3. Repairs
a. Roof repair costs (estimated over 20 years)
b. Interior damage repairs (estimated over 20 years)
4. Energy Savings
a. Estimated energy savings (over 20 years)
b. Energy rebates/incentives
5. Warranty
a. Cost for 15-year No Dollar Limit (NDL) warranty

What Really Makes a Roof Cool?

Cool roofing and sustainable (or “green”) roofing emerged as separate, but closely related, commercial roofing industry trends about ten years ago. Today, both cool and sustainable roofing continue to gain momentum, and they are driving change in commercial roofing market dynamics, roof system design and manufacture, product innovation, industry initiatives, selection priorities, building codes, and legislation. They are also sparking a considerable degree of discussion, disruption, and controversy due to their ongoing impact on the commercial roofing industry.

The overall objectives of cool and sustainable roofing have become widely accepted as desirable, sometimes mandatory, criteria for the design, manufacture and selection of commercial roofing systems. Cool and sustainable roofing have both been embraced by a host of industry associations and government agencies, many of which are trying to define the “roofs of the future” – including:

As industry groups continue to develop universal definitions and objectives for cool and sustainable roofing, government agencies at the federal, state and local level are implementing more standards, regulations and incentives to encourage or mandate the use of energy-efficient and/or sustainable roofing systems. These actions, combined with simple but powerful economic factors, are creating increased demand for a new class of High-Performance Roofing (HPR) systems that can satisfy traditional performance criteria – such as installed cost, performance and longevity – as well as relatively newer criteria – such as life-cycle costs, energy efficiency, and preservation of the environment.

In our next installment, we will discuss the High-Performance Roofing trend.

Working With A Roofing Contractor: Part 3

Who is Responsible For What?

Once the building owner has officially hired a roofing contractor, he or she can take steps to ensure the relationship is a productive one. It’s important to clarify at the outset the events that are and are not covered by the roofing warranty, so that everyone is on the same page and fully understands its contents. In the past, some roofing manufacturers and contractors have been less than forthcoming about the scope of warranty coverage. In some manufacturer’s warranties, roof damage from acts of God and third parties, such as when a satellite dish installer screws the dish directly to the roof, are not covered. The building owner should be aware of these types of warranty issues

Prior to issuing a warranty, to ensure that each roof installation meets our standards, Duro-Last’s Technical Representatives perform an evaluation consisting of four elements:

  • Quality of the welding.
  • Quality of the detail work.
  • Contractor’s adherence to specifications such as for roof attachment and sealant requirements.
  • Overall aesthetic quality of the job.

It’s important to identify the responsibilities of the manufacturer, the contractor, and the building owner once the roof has been installed and the warranty has been issued. With some roofing systems, the contractor is responsible for making repairs covered under the warranty for the first two years after the roof is installed, while the manufacturer is responsible for any warranty work for the duration of the warranty period.

Similarly, the building owner or facility manager should be aware of his or her responsibilities in upholding the warranty.

For instance, some warranties require the building owner to report any roof leaks within 30 days so that the leak can be repaired before the interior of the building is severely damaged. The building owner should also ask the contractor about charges involved in performing any repairs (including potential premium charges for “after hours” work), and the amount of time typically needed to respond to emergencies.

As with most business partnerships, knowing what to expect upfront makes a project run much more smoothly.

Is Roofing Part of Your Energy Management Strategy? Part 5

Regulatory Mandates

The obvious benefits of cool roofing systems have resulted in many federal, state, and local government initiatives designed to encourage or mandate their use.

Below is brief overview of Federal Energy Management Policy and Mandates. The full overview can be found here.

National Energy Conservation Policy Act (NECPA)

Signed into law in 1978, NECPA serves as the underlying authority for Federal energy management goals and requirements. It is regularly updated and amended by subsequent laws and regulations and is the foundation of most current energy requirements.

Section 543 of NECPA required a reduction in Btu/GSF of 20 percent by 2000, life-cycle cost methods and procedures, budget treatment for energy conservation measures, incentives for Federal facility energy managers, reporting requirements, new technology demonstrations, and agency surveys of energy-saving potential.

Section 102 of EPAct 2005 re-established energy reduction requirement for Federal buildings. The requirement uses a base year of fiscal year (FY) 2003 and requires reductions of 2 percent per year in energy use per square foot, leading to a 20 percent reduction in FY 2015.

In 2007, President George Bush signed Executive Order 13423, strengthening Federal environmental, energy, and transportation management. Section 2 of the Order set more challenging goals than EPAct 2005, requiring a 3 percent reduction in energy intensity per year and leading to a 30 percent reduction in 2015 compared to the base FY of 2003.

Also in 2007, President Bush signed the Energy Security and Independence Act of 2007 (EISA). EISA adopts the energy intensity reduction goals of Executive Order 13423 beginning in FY 2008 with a 9 percent reduction and increasing to a 30 percent reduction in FY 2015.

Click the links below for more detailed information.

Energy Policy Act of 1992

Executive Order 13221

Energy Policy Act of 2005

Executive Order 13423

Energy Independence & Security Act of 2007

Cool Roofing is a Win-Win Energy Management Strategy

Most building owners don’t need regulation to recognize a good thing when they see it. Even without regulatory mandates, PVC and TPO cool roofing systems have been the fastest growing commercial systems in America since the late 1990s. Many utility companies now offer rebates for using reflective roofing systems. These rebates – which can amount to several thousand dollars on large roof installations – are offered nationwide, not just in southern climates.

Best of all, cool roofing is a rare example where there are really no cost or performance tradeoffs for selecting an energy-efficient, environmentally-friendly system. The best single-ply cool roofing systems protect buildings from the rain, sleet, and snow just as well, or better, than alternative dark-surface roofing systems, and they can also play an important part in the energy management strategies of smart building owners and managers.

Factors To Consider When Purchasing A Roofing System: Environmental Impact

The drive for environmentally-friendly products extends to the commercial construction arena, including roofing systems. In this post, we will discuss some of the energy aspects of roofing: reflectivity, emissivity, and the solar reflectance index.

Environmental Impact – Part B

Rooftop reflectivity has received substantial attention during 2009, perhaps most notably in Energy Secretary Steven Chu’s remarks recommending that the world’s roofs be painted white. The upshot is that a roofing material’s ability to reflect solar energy has environmental implications, including its contribution to (or mitigation of) the urban heat island effect and impact on emerging carbon markets, among others. In fact, a roofing system’s energy efficiency is really determined by a couple of interrelated attributes.

Reflectivity (technically, albedo) is the percentage of solar energy reflected by a surface. The higher the reflectance value, the more solar energy that will be reflected from the surface.

Emissivity is the measure of how effectively a material sheds the heat it has absorbed. Materials with a high emissivity value may absorb energy easily, but they also radiate large amounts of it back into the atmosphere.

Roofing systems that provide both high reflectivity and emissivity are most likely to have a significant impact on a building’s energy cost. Some systems can reduce a building’s energy consumption by up to 40%.

The solar reflectance index (SRI) is a tool that evaluates reflectivity, emissivity, and other factors to determine a roof’s overall ability to reject solar heat. Its calculation is defines by ASTM E 1980-01 and is based on a formula that includes values for solar absorptance, solar flux, emissivity, the Stefan Boltxman constant, and other coefficients.

Standard black (reflectivity 5%, emissivity 90%) has an index of 0, and standard white (reflectivity 80%, emissivity 90%) has an index of 100. Very “hot” materials can actually have negative values and very “cool” materials can have values greater than 100. Materials with the highest SRIs are the coolest choices for roofing.

The Duro-Last Cool Zone® roofing system, a PVC membrane, has initial reflectivity and emissivity measurements of 87.5% and 95%, respectively, and a resulting SRI value of 108.

Here are the SRIs of some other roofing materials as measured by Lawrence Berkeley Labs and the Florida Solar Energy Center:

Roofing System




White EPDM





Metal, White




New, Bare

Galvanized Steel




Light Gravel





White Granular

Surface Bitumen




Dark Gravel




Black EPDM




Is Roofing Part of Your Energy Management Strategy? Part 4

Single-Ply Cool Roofing Systems

Many single-ply roofing systems have become popular in commercial applications due to their long-term performance, easy maintenance, and life-cycle cost benefits. Some of them have emerged as the best long-term cool roofing options. Their common attribute: high reflectivity.

  • Polyvinyl chloride (PVC) single-ply roofing systems have the best track record of long-term performance among white single-ply cool roofing systems. The first white PVC systems were installed in Germany during the 1960s, and their overall performance and life cycle cost benefits made these early systems popular in Europe during the 1970s and ’80s.
  • Chlorosulfonated polyethylene (CSPE) single-plies were the earliest widespread white roofing systems in the U.S., introduced in the 1970s under the Hypalon® brand. Although effective as a cool roofing system, Hypalon has not achieved the same commercial success as PVC, EPDM and other single-plies.
  • More recent cool roofing single-ply developments include the introduction of thermoplastic polyolefins (TPOs) and certain new co-polymer alloys (CPAs) during the late 1980s and 1990s.

Today, many single-ply roofing systems are available in white, including EPDM and modified bitumen, but PVC and TPO systems are the most popular and best-performing in terms of long-term reflectance. The National Roofing Contractors Association (NRCA) has identified the PVC/TPO thermoplastic single-ply category as the fastest growing roofing sector in America for several years. The coolest among these systems typically have solar reflectance ranging from 70 percent to 85 percent.

Installing a single-ply cool roofing system can save energy and money for building owners all over the United States.

The Cool Roof Rating Council was created to develop accurate and credible methods for evaluating and labeling the solar reflectance and thermal emittance of roofing products. The CRRC’s web site enables you to search for rated products as you investigate roofing systems that will help make your building as energy-efficient as possible.

In our final installment we will discuss Regulatory Incentives and Mandates.

Factors To Consider When Purchasing A Roofing System: Environmental Impact

You must consider many factors when your roof needs to be replaced or when you are constructing a building that requires a new roof. Reviewing these factors will help you to make the wisest roofing choice and get the best long-term value for your investment.

There’s a lot to cover in a discussion of the environmental issues surrounding roofing selections, so we’re dividing it up into two posts.

Environmental Impact – Part A

Today’s society calls for more products that are environmentally-friendly, and that drive extends to commercial construction products, including roofing systems. Several factors have a bearing on a system’s environmental impact.

When researching roofing systems, investigate the materials that are used in their production. During the past several years, PVC building materials have been scrutinized perhaps more than any other, largely due to production issues that date back more than 30 years. In fact, a recent USGBC report indicated that on the whole, PVC is as benign as other construction products, and in some cases may be the most environmentally-friendly option.

Many PVC single-ply membranes are also lightweight and can often be installed over existing roofing systems, eliminating costly and landfilling tear-offs and requiring less fuel to transport to the job site than other heavier materials.

Some roofing systems benefit not only the external environment, but the internal environment as well, contributing to better indoor air quality and occupant comfort. With optimized insulation and venting, some systems can also relieve positive air pressure to keep indoor air cleaner.

When researching roofing systems, learn what happens to manufacturing scrap as well as the system itself after the end of its useful life. Some roofing manufacturers recycle scrap into other commercial products like flooring, expansion joints, walkpads, etc. Furthermore, manufacturers like Duro-Last® have implemented recycling programs for PVC roof membranes after their useful roofing lives. Such programs keep waste out of landfills and reduce the need for virgin feedstock used in a number of construction products, including new roofing membranes.

In our next installment of Factors To Consider When Purchasing A Roofing System, we will discuss the energy aspects of roofing: reflectivity, emissivity, and the solar reflectance index.

Factors To Consider When Purchasing A Roofing System: Performance

You must consider many factors when your roof needs to be replaced or when you are constructing a building that requires a new roof: Price. Quality of the product being installed. Prefabrication. Installation disruptions. Ease of maintenance. Performance. Environmental impact. Life-cycle costs, and so on. It is crucial to review all of these aspects in order to make the wisest roofing choice and get the best long-term value for your investment.

This is the sixth post in a series discussing the issues involved in purchasing a roofing system.

Proven Track Record

How long has the roofing system you are considering been on the market? How has it performed? Has its formula changed over the years to improve performance? Is “thicker” really “better” when it comes to roof performance? Answers to these questions are vital to know in order to get the best roof for your building.

Hundreds of roofing systems are on the market today, and sometimes they seem to blend together and appear to offer the same qualities. Not true. Look at how long the roofing product has been around and then evaluate its success. Most manufacturers will be happy to direct you to satisfied customers who can describe how their roofing system solved a problem.

Thicker=Better? Not So Fast!

Some roofing manufacturers promote the idea that when it comes to roof performance, “thicker” means “better.” However, that is not necessarily the case.

Some manufacturers increase membrane thickness by adding more material to the bottom film layer but little to the exposed layer. However, increasing bottom layer thickness does not directly increase membrane performance. Rather, performance is a balance between film formulation, membrane thickness, and reinforcement.

Film formulation determines the flexibility of the membrane and its ability to resist crazing and cracking over time, plus protect against ultraviolet (UV) radiation.

Membrane thickness provides protection from water, snow, and ice elements.

Reinforcement provided by the scrim layer of the membrane is the source of the membrane’s strength. The scrim protects against natural elements such as wind and hail, and from human activities that can cause punctures and tears. Additionally, reinforcement gives dimensional stability to the membrane and strength against building movement.

If you buy or specify single-ply roofing systems, your decision should be based on membrane performance, not thickness alone.

In our seventh installment in this series, we will discuss roofing system features that have a positive impact on the environment.

Is Roofing Part of Your Energy Management Strategy?

Significant Savings Drive Demand for Cool Roofing

Cool Roofing Options and Choosing the Best Cool Roofing System

There are two primary types of cool roofing products on the market today: (1) reflective paints and coatings; and (2) single-ply roofing systems. Paints and coatings based on either acrylic or elastomeric chemistry can be an effective short-term solution for reducing energy costs, but most facility owners looking for long-term, low-maintenance solutions opt for a complete single-ply roofing system.

Many roofing products are on the market, which can make choosing the right one a challenge. Fortunately, several objective tools are available to help with the process. Choosing a system from the approved list of products in the EPA’s ENERGY STAR® Roof Products Program or from the Cool Roof Rating Council (CRRC) ratings chart is a good way to narrow down the selection process. Products on the ENERGY STAR list undergo rigorous testing before approval to ensure that they meet the established standard for reflectance.

In addition, the ENERGY STAR Roof Products Program has developed an energy savings calculator that projects the potential savings from installing a cool roof compared with alternative “non-cool” systems.

Here is a short list of important factors to consider when selecting a cool roofing system:

  1. Reflectance/emittance performance, both initial and after three years.
  2. Long-term track record of durability and performance.
  3. A good warranty backed by a solid, well-established manufacturer.
  4. Climate and weather extremes in a given location.
  5. Maintenance requirements and ease of repair.

In our next installment we will discuss: Single-Ply Cool Roofing Systems


Factors To Conside When Purchasing A Roofing System: Ease of Maintenance

You must consider many factors when your roof needs to be replaced or when you are constructing a building that requires a new roof: Price. Quality of the product being installed. Prefabrication. Installation disruptions. Ease of maintenance. Performance. Environmental impact. Life-cycle costs, and so on. It is crucial to review all of these aspects in order to make the wisest roofing choice and get the best long-term value for your investment.

This is the fifth post in a series that will discuss the issues involved in purchasing a roofing system.

Ease Of Maintenance

Once a roofing system has been installed, most building owners do not want to have to deal with it again. They do want to make sure that they get the most from their roof investment and, most importantly, that it provides long-term, leak-proof protection for their building.

If you’re in the market for a new roof, it is very important to understand the importance of the roof selection process and the impact it can have on your money and time. Both can be saved by matching the building design, building use needs and your capabilities.

Some systems can require extensive maintenance, such as re-coating, re-surfacing, new flashings, or re-spraying after a few years of service for the system to perform properly. Many require regular inspections and repairs in order to maintain warranty coverage. Then there are some roofing systems that are virtually maintenance-free, necessitating little to no upkeep when designed and installed correctly.

Consider how much time and money you are willing to invest in maintaining your roof or fulfilling warranty requirements. Clearly, most building owners will opt for a roofing system that requires less maintenance. However, even roofs that require little or no maintenance can benefit from periodic, common-sense inspections that can help keep drains and gutters flowing, vegetative overgrowth (trees) clear, ponding water a non-issue, and third-party damage minimal, especially following storms and other climatic events.

When looking at maintenance, it is important to ensure that the roof system is compatible with your building. As an example, roof systems with high emissivity and reflectivity will significantly reduce the stress put on cooling systems by dramatically lowering the ambient air temperature in summer that the units have to cool. This can lower energy costs as well as cooling system loads and maintenance. Facilities with rooftop grease vents should have roofs that are able to withstand grease exhaust. This will reduce or eliminate annual maintenance and resurfacing of these areas, which is necessary with asphalt based systems.

Additionally, it is critical that maintenance crews know how to correctly care for the specific roofing system that is installed on your building. Most roofing manufacturers provide instructions on how to maintain their systems, and they should be followed carefully so as to not void the warranty. It’s important to note that some manufacturers will only allow maintenance and repairs to be performed by the original installing contractor, or the warranty will be voided.

Thorough research on the care and maintenance requirements of each roofing system being considered will help you choose the right one for your building and help you customize your roof maintenance program to the needs of your facility.

In our sixth installment of Factors To Consider When Purchasing A Roofing System, we will discuss roofing system features that provide outstanding performance.