At the base of Maslow’s hierarchy lie the physiological needs humans cannot live without – food, water, clothing, sleep, and shelter. There are many ways to describe “shelter,” but it’s incredibly fitting that among the most common is “a roof over your head.” Walls are great, a floor is preferred, but without a roof, what sheltering properties would a shelter have? Roofing systems are one of the most valuable components of your property, and they sure do take a beating to ensure that you remain sheltered. So, when it comes time to take care of your roof, what do you need to know, and what can you do to protect it?
What are Roofs Made Of?
While a wide variety of material is available for flat roofs, we prominently see modified bitumen roofing systems. These systems are made up of sheets of polymer-modified bitumen with polyester and/or fiberglass reinforcements. The bitumen, a highly viscous constituent of petroleum, provides waterproofing, while the reinforcements add strength and prevent punctures. Assembled in a factory, modified bitumen roof systems are less labor-intensive to install, which can be cost-advantageous.
There is also a wide variety of materials used for shingles, including asphalt, wood, metal, slate, and tile. Wood shingles, generally used in areas with moderate climates, can provide good insulation but may not be ideal for extreme weather conditions as they are prone to mold and rot. Metal shingles, crafted from aluminum, steel, or copper, are durable, resistant to harsh weather, and are energy efficient as they can help lower cooling costs in hot climates by reflecting heat off the house. But being significantly pricier than asphalt shingles, they are much less prevalent. Shingles made from slate or tile are durable and offer a unique appearance, and are both suitable for hot and cold climates as they are natural insulators. However, both slate and tile shingles are significantly heavier than other shingle types, making their installation expensive. Tile shingles, often seen in Mediterranean or Spanish-style architecture, may even require a reinforced roof structure due to their weight.
Asphalt shingles are by far the most common shingle type, as they are affordable, simple to install, and come in a wide range of colors and styles. Asphalt shingles come in two main varieties, organic and fiberglass, both of which are coated in asphalt and granules that protect them from the elements and UV rays. Organic asphalt shingles have a paper or wood-fiber base, while fiberglass shingles are reinforced with a fiberglass mat. In hot climates, asphalt shingles may have a reflective coating to keep the home cool, and in cold climates, fiberglass is the preferred reinforcement as they can better withstand snow and ice. Compared to other shingle types, asphalt shingles are relatively inexpensive, as is their installation. Because they are so lightweight and easy to install, installation time, and therefore labor costs, are reduced. While not as long-lasting as slate or metal shingles, they are designed to remain durable in any climate and require minimal maintenance.
Roof Lifespan
So, exactly how long does a roof last? While this question is nuanced, both flat and sloped roofs have a useful life of around 20 years and can extend up to 25 years if they are well maintained. Sloped, asphalt shingle roofs necessitate replacement when there are multiple or recurring leaks and the shingles begin to cup, curl, or lift. Even if the shingles are largely watertight, water infiltration can permanently damage the underlying sheathing, greatly increasing the cost of a roof replacement. Because roof leaks may also be caused by issues with interrelated roof system components such as flashings, the warranty period on the shingles may exceed the life of the roof itself.
It’s important to note that warranties are an indication of product quality – not a product guarantee. For example, asphalt shingle warranties vary from 20 to 50 years and beyond. However, the scope is generally limited to the cost of the shingles caused by manufacturing defects, such as thermal splitting, granule loss, cupping, and curling. The cost of labor is rarely included, so if the shingles themselves fail, the labor to tear off and install new shingles is an extra cost. Some warranties may offer a no-dollar limit for replacement at an additional cost, effectively acting as an insurance policy, but these warranties also have limits and may not cover damages other than a product defect.
When it’s time to evaluate proposals for a new roof, we recommend taking the time to compare each proposal’s manufacturers’ warranty. You should determine the current cost to fix the roof should it fail soon and compare it with the total replacement cost for each warranty. Of course, you probably won’t make your decision based solely on the warranty, but it is an important aspect of choosing a provider that should not be overlooked.
For both sloped and flat roofs, there are two roof replacement methods available – an overlay or a tear-off. An overlay is the application of a new roof over the existing roof, and while this method is generally cheaper, there are significant disadvantages. For both sloped and flat roofs, overlaying a roof can hide defects in the underlying roof that can cause further, costly issues down the line. Flat roofs may require confirmation through a thermal scan that the underlying insulation is still in good condition and not saturated with moisture. If the insulation is saturated, an overlay is not feasible. For sloped roofs with asphalt shingles, an overlayed roof can cause excess heat absorption, resulting in accelerated deterioration of the old and new shingles, and an uneven appearance.
The tear-off method, on the other hand, includes the removal and full replacement of the entire roofing system. Flat roofs are fully replaced with new flashings and insulation, and sloped roofs receive new underlayments and flashings if required. While the tear-off method is a larger initial investment, it allows any area of defect or degradation to be properly addressed rather than covered up, preventing potential leaks and expensive repairs down the road.
What Poses a Threat to Roofs?
Water, specifically water infiltration, is enemy number one for any roofing system. Roof leaks can be caused by a myriad of issues, but generally, they can be grouped into one of three categories.
Regardless of what caused a roof leak, it’s crucial to make prompt repairs as water infiltration can have devastating effects on an entire house or building. When water penetrates the roof it can spread through the structure quickly, damaging ceilings, walls, and even floors. This moisture can weaken structural elements, cause wood rot, and promote mold and mildew growth, leading to compromised indoor air quality and potential health risks. Persistent or ignored leaks can damage insulation, which decreases thermal efficiency and increases energy costs. In the most severe cases, this moisture can lead to electrical hazards should it reach any wiring.
Hot weather can have several adverse effects on both sloped and flat roofs. Asphalt shingles and asphalt or rubber flat roof membranes lose their flexibility when exposed to prolonged high temperatures, causing them to become brittle enough to crack. Heat can also accelerate the loss of shingle granules, which are essential in protection from both UV rays and physical damage. Excessive heat can accelerate the aging of any roofing material, as well as the adhesives used on flat roofs. Damage done by heat may lead to water infiltration, so it’s crucial to consult a professional when choosing shingles or a roofing membrane in hot climates.
In cold climates, sloped roofs face the threat of ice dams. Caused predominately by inadequate or improperly installed attic insulation or ventilation, ice dams form when warm air accumulates at the peak of an attic while the roof eaves – the edges where the roof “hangs” over the home – remain cold. As the warm attic air melts the snow at the ridge of the roof, water runs down the slope and lands at the cold roof eaves, re-freezing to form a buildup of snow and ice. This buildup often traps water that seeps under shingles, ultimately causing water damage to not just the roof deck, but also the building interior.
Insulation and ventilation are two of the most important components of any roof. Both components work to prevent moisture buildup, which is the cause of all those words you never want to hear – rot, mold, and mildew. Moisture buildup can also warp the roof’s sheathing, deteriorate shingles, and eventually damage building interiors. Outside of controlling attic moisture, ventilation and insulation work together to maintain energy efficiency. Proper attic insulation ensures minimal heat gain and loss between the attic and the living space, and proper ventilation removes excess heat from the attic that can radiate into living spaces. Combined, air conditioners don’t have to work as hard, and energy consumption can be reduced year-round.
What Can You Do to Maintain Your Roof?
Regular, thorough inspections are essential in identifying and addressing potential roofing system issues before they escalate and should be paid for through the operating budget. Roof inspections conducted by a professional are, by far, the most effective way to maintain any roof, and should ideally be completed twice a year. Inspection costs do pay off, as even the slightest reduction to the roof’s useful life can have a large impact on the overall cost of either a partial repair or full replacement. While some minor repairs could be safely made on your own, it will always be best practice to promptly call a qualified professional if you notice signs of deterioration or damage.
So, what can you do to maintain your roof and extend its lifespan? After severe weather or heavy rain, sloped roofs should be examined for damaged or missing shingles, and those with flat roofs should note water that remains pooled 48 hours after a heavy rainfall as this may indicate a clog. Debris of any kind should be cleared from roof surfaces, and gutters, drains, or downspouts should be cleaned regularly to ensure proper drainage. Overhanging branches should be trimmed to avoid an accumulation of leaves or moss, and algae growth should be cleaned with a roof-safe cleaner. In homes with sloped roofs, ensuring proper attic ventilation is key to reducing heat buildup and moisture.
Semi-annually, perimeter flashing on flat roofs should be checked for loose fasteners, deflections, and sealant deterioration, and the entire roof surface should be inspected for ruptures or damage including blistering or bubbling. In areas where there may be foot traffic, sharp debris or trash should be removed and any areas of crushed or damaged insulation should be noted. Because any type of liquid can damage the roof’s membrane, mechanical equipment should also be checked for oil spills or other contaminants.
Lastly, foot traffic on any roof should be kept to a minimum. That cozy rooftop restaurant is not the norm – flat roofs used for recreational spaces are specialized to withstand pressure and may have additional structural support. The vast majority of roofs are simply not built to be walked on. Flat roofs can experience damaged felt or punctured membranes, and shingles of any type can experience cracking, breaking, or scuffing. Even if the shingles don’t crack, walking on them can weaken or crack the underlayment. Most importantly, it’s a safety issue. Other than the obvious risk of falling, it’s impossible to determine if an invisible roof component is damaged, rotting, or degraded, and you may end up causing excess damage. In some instances, having walked on your roof gives insurance companies the right to deny further claims.
Your roof is a large, valuable investment, and should be treated as such. With a proper understanding of your roof, effective maintenance practices, and regular inspections, associations can extend their roofs’ useful lives, save money on costly repairs, and safeguard the structural integrity of the entire home or building. The roof over your head protects you – why not protect it?
