Services & Maintenance: Three Steps To Roof Replacement

By Bryan Brunow and Eric Hasselbusch

Published in the November 2012 issue of Today’s Facility Manager

Working in a perfect environment, a facility manager (fm) would implement a sustainable roof program with the goal of achieving lowest cost of ownership while extending asset life. Three factors—proper design, quality construction, and proactive maintenance—have the greatest impact on achieving this goal. Meanwhile, reduced risk to personnel and property damage, fewer materials entering landfills, extended roof replacement cycles, and fewer headaches associated with emergency repairs are additional benefits of a sustainable roofing program.

Building Code and Rating System Changes

By Barry Reid, LEED AP BD&C

Roofing systems play a significant role in the energy efficiency performance of a facility. Photo: Georgia-Pacific Gypsum
Roofing systems play a significant role in the energy efficiency performance of a facility. Photo: Georgia-Pacific Gypsum

This is no time for a leaky or otherwise faulty roof. Today’s roofs not only handle the traditional role of protecting facilities and their contents from the elements but must also be sustainable—along with providing increased energy efficiency and further extending the life of facilities. Advancements in energy technology, including solar photovoltaics and roof mounted wind turbines, have hastened the roof’s evolution into a multiuse platform.

This year, numerous changes to building codes have occurred. Many of them are driven by energy efficiency mandates, which have further heightened the importance of well performing commercial roofs.

The alphabet soup of code abbreviations includes numerous new or updated codes. Two in particular—the 2012 International Green Construction Code (IgCC) and the 2012 International Energy Conservation Code (IECC)—have significant impact on new or reroof projects. Next year, a new version of LEED—called LEED v4 and currently being reworked to address stakeholder concerns—is also expected to be released.

Following are some highlights of the changes brought about by the new IgCC code and the updated IECC code, and their impact on the roofing industry.

IgCC. The first green building code developed in the International Code Council (ICC) code development process, the IgCC is designed to reduce the negative impacts of the built environment on the natural environment by establishing minimum green codes. The IgCC was developed using the ICC development process in association with the USGBC, IES, ASHRAE, ASTM, and AIA. It is intended as an overlay code for the other ICC codes that have been adopted by state or local jurisdictions. Thus far, the IgCC has been implemented by several states and municipalities, with others soon to follow.

Key IgCC roofing highlights include:
• Addresses roof surfaces, roof coverings, solar reflectance, thermal emittance, and vegetative roofs
• Increased insulation above roof decks and lower product volatile organic compound (VOC) emissions

IECC. The 2012 IECC calls for facilities to achieve a 30% increase in energy efficiency over the 2006 IECC. This sixth edition of the code illustrates the growing importance of ensuring that all facilities are achieving high levels of energy efficiency in congruence with relevant model building codes.

A few key IECC roofing highlights:
• Increased insulation for low slope roofs with above deck insulation.
• For metal roofs, R-5 thermal blocks are required (or U-factor Compliance Methods must be used).
• Solar reflectance and thermal emittance requirements and options for low sloped roofs in southern climate zones.
• Roof solar reflectance is required in Climate Zones 1-3 for low sloped roofs, directly above cooled conditioned spaces.

LEED v4. This version of the LEED green building rating system from the USGBC is expected to favor a life cycle approach for products that are installed in LEED certified buildings and assemblies. It is expected to reward transparency for sustainable manufacturing, socially responsible raw materials sourcing, and use of products with low VOC emissions.

Expected LEED v4 roofing highlights:
Updates to the roof Solar Reflectance Index (SRI) requirements
Credit for “Heat Island Reduction” that combine non-roof and roof elements in measuring heat island effect

The code mandates described have also increased demand for air barriers and continuous insulation that improve energy efficiency and reduce operating costs. Also, today’s roofing systems are more complex, requiring more protective measures to extend service life. Both of these enhancements add importance to selecting and installing roofing cover boards properly, which heightens the performance of these and other elements of the building envelope.

With these new codes and rating systems in place or pending, the value of installing durable and energy efficient roofs is further magnified.

Reid is sustainability/product manager for Georgia-Pacific Gypsum, a building products company based in Atlanta, GA.

Unfortunately, most fms do not have the perfect environment. Often, there are competing interests, funding issues, personnel decisions, and changes in project prioritization, to name a few. In addition, many organizations have different levels of acceptable risk they can assume when dealing with deteriorating or aging roof systems. All of these factors impact how fms decide to manage their roofing assets. What quite often begins as a proactive plan can quickly become a reactive plan to replace a roof when it fails.

When fms find themselves in these types of situations, how can they ensure they obtain the right system installed correctly and at a fair market price? With dozens of roofing material options, thousands of roof component combinations, and other criteria to consider, such as building codes, wind zone, deck type, roof traffic, and insurance requirements, determining where to start can be a daunting task.

Fms can begin to develop sound roof replacement strategies by considering these three questions:

  1. How will the appropriate roof design be determined?
  2. What measures will ensure the roof system is constructed as designed?
  3. How will the system be maintained after it is constructed?

Step One: Design

Proper design is the foundation of a successful roofing project. Just like a house built with a poor foundation, an improperly designed roof will fail. Unexpected repairs can be inconvenient and costly.

There is the old adage, “You get what you pay for.” Fms should choose a design professional who has the expertise and knowledge to design a roof system that follows applicable codes and meets the facility’s specific needs and requirements. In addition, design parameters should not be dictated based on relationships with manufacturers or contractors.

The following is a list of criteria for fms to consider during the design phase:

  • Occupant goals and requirements
  • Building codes and insurance requirements
  • Life cycle costs
  • Risk management
  • Budget limitations
  • Sustainability (energy, durability, storm water, materials, recycling, etc.)
  • Building form and function
  • Structural considerations
  • Deck, substrate, and surface components and conditions
  • Contaminants (atmospheric and rooftop)
  • Roof traffic
  • Roof access
  • Slope and drainage
  • Material installation requirements
  • Compatibility of materials
  • Aesthetics
  • Geographical location
  • Maintenance program

Here are a few of those criteria explored in further detail.

Building form and function. Often during the life of a facility the processes taking place inside change from when originally constructed. Changes such as adding dock doors, transitioning from unconditioned to conditioned space, and contaminants being discharged on the roof surface can have a significant impact on the performance of the roof system.

Roof contaminants. Fms should identify chemicals, oils, or animal fats discharged on the roof. Depending on the type and quantity, contaminants can have a significant, negative impact on the performance of certain roof membranes, resulting in premature failure. By identifying potential contaminants before a roof system is designed, fms can evaluate alternative strategies such as: incorporating containment basins, using different roof membranes, modifying ventilation systems, or increasing maintenance to reduce the impact on the roof.

Codes and insurance requirements. Federal, state, and local building codes as well as insurance requirements have a significant impact on roof design. Storm water runoff, reuse or recycling of materials, air quality issues, energy efficiency (e.g., R-values), and wind uplift rating requirements are several design elements that may be impacted by code and insurance requirements. [See accompanying sidebar for more on building codes.]

Using improper materials to maintain this metal panel roof resulted in a temporary repair and increased the cost for proper repairs. Photo: Benchmark, Inc.
Using improper materials to maintain this metal panel roof resulted in a temporary repair and increased the cost for proper repairs. (Photo: Benchmark, Inc.)

Slope and drainage. Water is the number one enemy of roof systems. Fms should ensure—and building code requires—a roof is designed with positive slope and the necessary drainage devices and emergency overflow.

Finally, when beginning the design phase of the project fms should consider incorporating preliminary design options as part of the process. The use of preliminary designs allows fms to compare various design elements to available budgets, so they can make informed decisions.

The most important aspect of the preliminary design is it ensures the designer and client discuss project requirements and design options prior to completion of the final design. For instance, if the designer missed critical information related to insurance requirements or roof contaminants, the fm could end up with a roof that fails prematurely and may not be covered by insurance.

Step Two: Construction

During construction, new wooden nailers were installed on top of existing, rotted wood nailers at the perimeter roof edge. Photo: Benchmark, Inc.
During construction, new wooden nailers were installed on top of existing, rotted wood nailers at the perimeter roof edge. (Photo: Benchmark, Inc.)

Embarking on the construction phase of a roofing project with well designed plans, including clear and detailed specifications, puts fms in the position to execute a cost-effective and successful project. Just as critical, fms need to ensure their design professional effectively communicates with the contractor and other project participants.

For the contractor, finding qualified labor, effective project supervision, working safely, and incorporating a quality control process to ensure the roof is installed as specified are the primary factors that will determine the success of the project once construction begins. Because these factors are critical to the project, fms should be aware of and understand how these factors may impact the project.

According to the Bureau of Labor Statistics, roofing is the fifth most dangerous occupation in the United States, with a fatality rate of 34.7 per 100,000. In addition, the roofing industry experiences a higher proportion of workers leaving the job each year in comparison to other construction trades. This high turnover rate can create significant challenges for construction project supervisors.

When the distractions, risks, and complexity associated with a roofing project are considered it is not surprising to experience installation errors that if not detected will negatively impact long-term performance.

Step Three: Maintenance

Once a roof system has been successfully designed and constructed, fms will want to protect their investment by considering maintenance as a cost-effective strategy in maximizing the service life of the roof. There is significant industry information that supports implementing a roof maintenance program to extend roof life and reduce life cycle costs.1

Not including an expansion joint in this wall flashing detail during the design phase resulted in wrinkled flashings and open seams. Photo: Benchmark, Inc.
Not including an expansion joint in this wall flashing detail during the design phase resulted in wrinkled flashings and open seams. (Photo: Benchmark, Inc.)

The best time to develop a preventive maintenance program is during the design phase. The type of roof system impacts the maintenance program that will be considered. A simplified approach includes inspecting roofs twice per year and after major weather events. Cleaning debris from drains and identifying and fixing minor problems (e.g., punctures, caulking failures) before they require major investment to repair or replace help ensure long-term performance.

The sooner a maintenance plan is implemented, the more fms will save in the long run. Failure to implement a roof system properly will likely result in a shortened life (average life expectancy of 17 years).2With a little planning and a capable team, a well designed, constructed, and maintained roof can meet or exceed a design life of 20 to 30 years while protecting people, property, and production.

Eric Hasselbusch
Eric Hasselbusch
Bryan Brunow
Bryan Brunow

Brunow is a staff consultant and Registered Roof Observer (RRO) with Benchmark, Inc., a roof and pavement consulting firm based in Cedar Rapids, IA. Hasselbusch is an account manager and marketing director with Benchmark, Inc.

1The decision not to employ an aggressive roof maintenance program is costing owners between $0.10 and $0.15 per square foot per year. Dennis Firman, P.E., U.S. Air Force.

2Roof Longevity and Replacement Report, funded by the Roofing Industry Alliance for Progress. Study completed by Ducker Worldwide.