During the last several years, manufacturers have changed how they make roof shingles, in particular: asphaltic fiberglass roof shingles on houses.
Some people are only concerned about the cost of roofing. Other people are just interested in the appearance. Most people may not know what the typical kind of roof shingles are made of these days.
WHAT ARE ROOF SHINGLES MADE OF: First there is a fiberglass sheet, which is then coated with asphalt on the rear and top, then mineral granules are impregnated into the top surface. Then asphaltic adhesive stripes are applied to the nailing zone, about halfway up the 12″+/- shingle height. There are typically at least 2 of these layers adhered together to result in an architectural laminated roof shingle today. Laminated roof shingles result in heavier weight, more durable construction, more water resistant capabilities and deeper shadow lines for improved aesthetics.
HOW LONG DO ROOF SHINGLES LAST: How long do they last? Perhaps 10 years to 50 years, according to manufacturer’s warranties. Or even your “lifetime.” From this architect’s experience, perhaps 15 years is normal, and maybe 25 years is nearing the upper end or so, for the thicker, heavier products.
WARRANTIES: Rand Soellner, AIA, just reviewed the product data sheets from some of the major residential roofing manufacturers and also talked with major material suppliers in the SE USA. For their middle-upper end fiberglass asphaltic roof shingles, it appears that you can obtain a warranty that completely covers labor & material to replace a roof that has manufacturing defects for the first 10 years of the installation. Then the warranties typically become prorated coverages after that. So when you get down to the last few years of a 50 year warranty, there might not be very much economic value associated with those last few years. Also, the likelihood of anyone keeping asphaltic fiberglass shingles on their roof for half a century without developing some serious problems is unlikely, despite what any warranty might indicate. Also, the main answer to how long fiberglass-asphaltic roof shingles last mainly depends on how thick and heavy the materials are in the manufacturing of the shingle, along with the quality of those materials, in particular the flexibility and durability of the asphaltic coating, the composition of the fiberglass sheet, and the mineral granules and any added materials to provide additional positive characteristics.
ALGAE RESISTANCE AVAILABLE: For instance, zinc and/or copper granules can be added to the limestone granules to provide some resistance to algae growth on your roof shingles. The calcium carbonate in the mineral granules is sure to propagate algae growth without something to curb that effect, so having an algae-resistant shingle is a wise investment.
WEIGHT & THICKNESS: Also, it is smart to obtain a heavier, thicker shingle as well, if you can obtain this information from the manufacturer. It is becoming more difficult to get answers to questions about the weight of roof shingles these days, as it once was one of the main determinants as to the quality and durability of an asphaltic fiberglass roof shingle. However, some companies, like GAF will not provide this information, as they feel that their latest improvements in the quality of the asphalt they use in the manufacture of their shingles should be the most important factor, and there is some logic behind that theory. CertainTeed still posts their roof shingle weights and that is helpful. Their “Landmark” series offers 240#, 260# and 300# weight roof shingles. These weights are per “Square”. A roofing “Square” = 100 square feet. So, the installed weight of the “best” Landmark roof shingle = about 3 psf (pounds per square foot). CertainTeed offers a “Lifetime” warranty on their “Premium” (300#) Landmark shingle, 40 years on their Landmark Plus (260#) shingle, and 30 years on their Landmark shingle. GAF’s comparable to this is likely going to be their “Timberline” series, which is the outgrowth of the previous Elk Prestique II family. Elk was bought out by GAF within the last several years and their product re-formulated within GAF’s latest technology to reinvent and hopefully improve asphaltic fiberglass roof shingles.
COSTS: Being largely a petrol-chemical product, asphaltic fiberglass roof shingle prices will be varying widely from week to week and month to month, as the oil that went into their manufacture varies in price. One of the major material providers for residential construction in the western North Carolina area, Jennings Building Supply, told Rand Soellner that their pricing was “good for today”, whenever they quoted numbers to contractors these days. All of these products discussed in this post are architectural grade, not the low end and not the upper end. They are mid to upper-middle products. For a 240# architectural grade asphaltic fiberglass laminated roof shingle, the price (for today) might in around $94/square (that’s $0.94/sf of installed area) and that’s just for the material, no tax, no delivery and no installation. For the thicker, heavier grade (300#) today’s price might be somewhere around $130/square (that’s $1.30/sf of installed area), once again not including tax, delivery or installation.
So, if your roof happens to be 40′ x 60′ of actual surface area = 2,400 sf. Then, for the upper mid-grade roof shingle cost of $1.30/sf, your new roof material might cost about $3,120.
We have heard that perhaps for a new roof, the labor cost might be in the $0.80/sf range, not including other factors, like high-performance waterproof underlayments. So, excluding the underlayment, a new roof of the sort described herein, upper-mid range might cost about $2.10/sf to install. Multiply that times a 2,400 sf roof = $5,040. If you are replacing an existing roof, that will be an additional cost. We have seen numbers for the tear off and clean up for a medium pitch roof in the $1/sf range.
So, labor being not something that should vary significantly based on the shingles involved, it is actually a better buy to use a heavier, higher quality roof shingle, because it just might end up lasting a very long time, much longer that the cheapest, lightest roof shingles.
INSTALLATION: Nails. NO staples. The nails, if galvanized or aluminum should last as long as your shingles. Staples are thin pieces of bent wire and will probably rust clean through or pull out in high winds. You will void manufacturer’s warranties if you use staples. Wind resistance is a combination of the weight of the shingles, plus the number of proper nails installed along the nailing strip, plus the quality of adhesive along the nailing strip. On most asphaltic fiberglass roof shingles, there are adhesive strips of asphalt along the approximate mid-point of the shingles, which is where the nails are to be installed. When the sun heats the shingles, this adhesive melts, and secures the top shingle over the bottom shingle, providing greater water penetration resistance and wind tear-off resistance.
FIRE RATINGS: You might as well select a roof shingle with a Class A fire resistance rating. This comes with most asphaltic fiberglass roof shingles these days.
WIND RESISTANCE: You can obtain 130MPH wind resistance and even more, depending on the weight, type and thickness of roof shingle and the number and type of nail used to install them. For instance, according to at least one shingle manufacturer, the difference to get a roof shingle from a normal lower rating up to 130 MPH is instead of using 4 nails, use 6. Big deal. It is worth another couple of nails per shingle to obtain a higher wind resistance that could occur if your house greets a tornado or hurricane, or simply gusty storms in your area.
See Rand Soellner Architect for guidance on your next roof and your next house design: 1. 828. 269. 9046