By RK Kliebenstein
“You’ve come a long way, baby” was the advertising theme in October 1968 when Philip Morse launched the Virginia Slims cigarette brand. The self-storage industry was in its infancy back then, and fortunately, it’s fared much better than the Slims. In fact, the slogan could easily be attributed to today’s storage product. From the days of wood garages or rows of metal buildings with chain-link fence to sleek, state-of-the-art buildings, self-storage has certainly come a long way.
Modern facility design includes many types of building materials. You might see everything from soaring glass atriums, like those used on Westy Self Storage properties, to the glossy single-story buildings used by Metro Self Storage. Some of the greatest evolution has come from the use of advanced materials like Galvalume insulated panels, tilt-up panels, stone and EIFS (exterior insulation and finishing system), which provide an array of textures that complement more traditional materials.
One of the most important elements of a project design is the roof. In terms of both new construction and maintenance, it’s also one of the largest building expenses.
As our industry has matured, many roofs have aged and are now well beyond their originally intended life cycle. Remember, many self-storage projects were built as “land banks,” meaning self-storage was an interim use while the owner awaited a better use for the land. In many cases, the replacement use never materialized, and buildings intended for 15- to 20-year life spans are now entering 30-plus years of operation. This has caused owners to look for repair and replacement options. Let’s take a look at some of the designs and materials that are reshaping the look and quality of today’s self-storage roofs.
Materials and Types
Just as the industry has matured, so have building products. Roofs now come in many shapes and sizes, as do the materials used in their construction, repair and retrofit. Design and materials will differ by location. While few self-storage properties use slate shingles, stone slabs, tile or wood shake, and ceramic tiles are an unpopular choice because of their weight, there are several materials suitable for storage roofs.
Shingles are common on wood truss and frame buildings. Most often, the shingle roof sheets are made from a heat process—often bitumen-based—most popularly known as asphalt shingles. They contain a ceramic or fiberglass mat and a ceramic or composite grit. Some will contain asbestos. While durable, they can cause health concerns and may be expensive to dispose of if you have to replace large quantities.
There are some newer rubber shingles that contain ultraviolet-light inhibitors and can last up to 50 years. Some owners have also chosen to use an interlocking metal shingle. While they have a long life, they can be costly.
Membrane roofs are popular for low-pitched roofs, often flat roofs, though they’re less frequently used to retrofit the common corrugated-metal roofs used in self-storage construction. These heat-fused panels can be made of rubber membranes glued together with contact adhesive or tape. Plastic sheets, known as thermoplastics, can be fused with hot air, creating a single membrane. These roofs can be repaired and rewelded if necessary. In some applications, the drawback may be that the natural “breathing” or aspiration of a roof is interrupted, and moisture may not properly escape, so other methods of ventilation must be employed.
Roof coatings are increasingly popular, and warrantees are available for up to 20 years for standing-seam roofs and 15 years for screw-down construction. The popular aluminum-based products not only provide a good solution that prevents water intrusion, they can act as insulation or a “cool roof” to reduce heat.
Also increasing in popularity are spray-polyurethane systems. These are made by combining a two-liquid component, which forms the base of an adhered roof system. They can be installed in various thicknesses to provide slope-to-drain or meet a specified thermal resistance. Protective surfacing is then applied to the foam to provide protection from the elements.
The first component of a spray-polyurethane roof is rigid, closed cell, foam insulation. The foam is composed of two components: isocyanate and polyol. Transfer pumps are used to get the components to a proportioning unit that properly measures and mixes the two in even ratios, and then heats and pumps them through two hoses. The components are mixed at the spray gun, which is used to apply them to a substrate.
The second component, the protective surfacing, is typically a spray-applied elastomeric that may be a membrane, such as a fleece-backed thermoset single-ply membrane. The purpose of the surfacing is to provide weatherproofing, protect the foam from ultraviolet exposure, provide protection from mechanical damage, and assist with the fire-resistant characteristic of the roof system.
Roof replacement in self-storage is expensive and can be disruptive to business. For this reason, many owners would rather cover an existing roof than replace it. Some will choose to even add an entirely new roof and leave the existing roof in place, usually if they’re looking to add climate-controlled space or correct insufficient pitch.
Attachments and Accessories
Ventilation covers. These penetrations are available for plumbing stacks and air vents. They can be a common source of roof leaks and need to be protected from the elements as well as intrusion from animals and pests. Look for products made specifically to work with your type of roof and vent. Protection ranges from simple grills that fit over plumbing stacks to more complex air vents that are large enough to displace air but designed to prevent ice, snow and water from entering the buildings.
Snow blocks or stops. These devices prevent avalanche occurrences during heavy snow fall in which large quantities of snow and ice may accumulate and slide off roofs, potentially causing personal injury. These devices allow snow and ice to melt slowly. Available in a variety of materials, including polycarbonates, they should be installed properly to avoid roof damage. Snow stops can be installed at the time of original construction or as a retrofit to existing buildings.
Gutters. Improper use or a lack of gutters can be a cause roof failure. Buildings without them can experience ponding that deteriorates the roof. If water builds up and doesn’t flow properly, it can freeze, creating stress on roof components. Safety is also a major concern. Gutters help to prevent sheets of water or snow from falling in front of unit doors, protecting tenants and their possessions during an in-climate move.
Gutters have a tendency to collect leaves and debris and often become damaged or inoperable. It’s important to keep them clean, and there are several products on the market to help self-storage operators inspect and maintain them.
One of the most technologically advanced tools is the iRobot cleaner that travels gutter runs. It includes an auger and brush system that frees up clogs and cleans the gutter. Battery-operated and remote-controlled, it also has an automatic mode that allows it to run by itself. When used regularly, iRobot is useful for the long gutter runs that are typical in self-storage buildings.
Self-storage is one of the most actively managed commercial real estate types. As in the hospitality industry, its evolution is driven by product development, including building materials for roofs and other building components. By seeking more economical, effective and aesthetic solutions, self-storage owners and operators will keep all their roof-design needs covered.
RK Kliebenstein is vice president of acquisitions for Metro Storage LLC, a privately owned, fully integrated real estate operating company specializing in the acquisition, development and management of self-storage facilities nationwide. He’s also a frequent speaker at industry events. For more information, call 847.235.8965; e-mail [email protected]; visit www.metrostoragecorporate.com.