The three homes featured above were re-roofed by Caldwell’s Roofing, with before and after pictures taken.
Roof #1: Re-Deck & Re-Roof
The first roof in the slideshow of residential roofing photos was a good example of some rare cases where a second layer of decking is needed, in addition to changing out the shingles.
Residential Roofing Photos: Roof with Extra Layer of Decking Added
Most homes use either 7/16″ OSB (“oriented strand board”) or 3/8″ plywood as the decking material. A 1/8″ gap is left along all the edges to account for expansion and contraction of the material due to temperature changes. However, some homes were built with wood planks (between 4″ and 12″ wide) or wood strips (less than 4″ wide) as the decking material. You might think this is good, but in reality, it’s often a problem. The planks/strips can twist, warp, shrink, and reject nails over time (especially if there is insufficient attic ventilation). This means an uneven surface for the shingles, a surface that can cause tears, a surface that may not hold new shingle nails tightly, and a surface with large gaps between boards that will allow nails in that gap to wiggle free and create leaks. In short, it can really be a disaster, if it’s in bad shape. A knowledgeable roofer will be able to assess your condition and offer his or her gut feeling, although they may request a “waiver of liability” as they may not be framing engineers! In some cases, if there are not significant gaps nor major twisting, the reference book The NRCA Roofing Manual: Steep-slope Roof Systems (2013) suggests that you may be able to re-roof successfully without adding a new layer of decking on top of the wood planks. However, if the gaps are 1/4″ or greater, it is advisable to lay a secondary layer of decking of OSB or plywood on top of the planks (at minimum), to provide a better surface for a new roof. In the case of this house, after stripping the shingles off, the homeowner did want to go back with a new layer of OSB before installing the new shingles. Good decision.
Roof #2: An Attic-Ventilation Nightmare
The second roof in the residential roofing photos slideshow illustrates a second, albeit often-neglected, important aspect of roofing – the attic ventilation.
This Roof Required Lots of Work to Bring the Attic Up to Ventilation Specs
Many homeowners (and even roofers) never make much of a connection between shingles and attic ventilation, but they ought to. In fact, to practice the roofing trade with discipline, one must fully understand the critical importance of attic ventilation. Attic ventilation is important for many reasons:
- Without it, asphalt shingles develop heat-blisters in the summer and the roof often fails prematurely, often at half or even one-third of it’s intended life (that’s a lot of wasted money!).
- Without it, most (if not all) shingle manufacturers’ warranties are considered null and void. The fine print often spells out that having attic ventilation up to code is requisite.
- Without it, you get terrible heat build-up in your attic in the summer (at least in the South) that drives AC bills up and reduces the effective R-value of your attic insulation.
- Without it, moisture and humidity from the home can get trapped in the attic and lead to microbial growth (experts estimate some 58% of childhood asthma is correlated to improper attic ventilation!).
- If you’re into green issues, a poorly-ventilated attic means wasted energy and wasted materials (the roof has to be replaced more times over the life of the house).
If that’s not enough to concern you, consider the fact that, according to shingle manufacturer GAF®, some 9 out of 10 homes lack proper ventilation! Is that not crazy, or what?
With an issue as important as attic ventilation is, you’d think people would be more concerned about it. Hopefully those statistics will change as people become informed of the importance of correct ventilation.
In the case of this house, Caldwell’s Roofing posits their educated guess that it was originally a shake-roof house. There was, many decades ago, a time when wood-shake roofs were being built commonly. Since air could “breathe” through the wood shakes, architects didn’t see any need to design the homes with any soffit overhangs (the part of the roof that hangs over the house). The problem was, once it was time to replace the wood-shake roofs, roofers simply slammed some asphalt shingles on top (sometimes tearing off the shakes, first), without addressing ventilation needs. Problem was, asphalt shingles don’t breathe. Even though roofers sometimes cut in a ridge vent (or there may have been gable vents on the sides), there was no place for air to get into the attic, thus rendering the ridge or gable vents utterly useless. But the problem was even greater. Even if someone wanted to allow air intake at the soffit, there was no way to do it, since the architect hadn’t designed any roof overhangs!
When Caldwell’s Roofing was first called out to take a look at this roof, they were asked to “repair” whatever had to be repaired. To their amazement, they found large framing nails protruding out of the decking and through the shingles! And, it wasn’t an “isolated occurance” – there were shingle tabs popping up all over the roof! What they determined was that, due to the extreme heat build-up in the attic caused by the lack of ventilation, the framing members were squeezing the nails outward, and pushing them out of the roof. Needless to say, Caldwell’s Roofing was concerned that, should they just remove and replace all the shingles, nails would continue to poke their way through the brand new roof! So, they suggested to the homeowner that new decking be installed over the wood strips (the same as on the previous house that was discussed), but they knew they also had to provide the much-needed attic-ventilation. After studying a few options, including The Edge™ by Air Vent, Inc., they decided to order some Pro Flow™ Vented Drip Edge, which is offered by the same company.
They cut a strip of decking back at the edge of the roof, enabling air to enter through the drip edge, pass through the cut-out at the bottom of the roof decking, and get into the attic. But there was another problem – after cutting the decking back, they found that solid blocking had been installed between every rafter (i.e., the blocking would render the vented drip edge useless)! This meant that Caldwell’s Roofing had to bust enough of the blocks in half in order to allow adequate air to get in.
Both Layers of Decking Have Been Cut Back in Preparation for Vented Drip Edge
When everything was said and done, Caldwell’s Roofing was able to bring this home with essentially zero attic ventilation all the way up to a 1:150 ratio of NFVA (“Net Free Ventilating Area”) to attic footprint area. This is twice as good as code’s requirement of 1:300. Caldwell’s Roofing also designed the new ventilation system at the requested 50:50 balanced ratio of half the ventilation area being at the ridge, and half of it at the soffit.
The vented drip edge, that was spoken of, provides 9 square inches of NFVA per lineal foot. Caldwell’s Roofing owner, Brad Caldwell, did the math to ensure an attic with ventilation exceeding code’s specs.
This Roof Required Lots of Work to Bring the Attic Up to Ventilation Specs
Notice that you can’t even notice the vented drip edge, which is the main reason Caldwell’s Roofing opted to use it instead of some other options. If you stand right under it, and you know what to look for, you can sort of see it; but it blends in perfectly with the roof to the “Average Joe.”
Roof #3: An Illustration of the Need for Roof Maintenance
Our last of the three residential roofing photos serves as a reminder to make sure you keep your roof properly maintained. You can do that by calling a reputable roofing contractor and seeing what they advise. If your roof is surrounded by, and under, a lot of broad-leaf trees, roofing maintenance may be something you really need to spend more on. That was the case for this house.
Leaves Piled on a Roof Can Hide Roof Damage and Can Deteriorate Shingles
Leaves were piled all over the roof, and in particular, on a back slope that was difficult to get to or even to see. There was an 8″-diameter hole in the roof in the back where a branch had punctured the roof! However, there were two or three other holes where water was pouring into the house, and one of the holes was over a wall, where the water could “hide” its descent down to the floor, where it was badly warping the hardwood flooring planks! Once Caldwell’s Roofing began the re-roof, they discovered moldy insulation, rotted rafters (the roof was about to cave in in one section – no joke!), and warped decking. Squirrels loved the situation, but it was wreaking havoc on the poor home.
Lack of Roofing Maintenance Meant an 8-Inch-Diameter Hole Was Hidden By Leaves!
After tearing off the shingles, Caldwell’s Roofing replaced the damaged framing members and bad insulation, then replaced warped decking in some badly-affected areas. Finally, they installed new felt paper and dimensional shingles.
As a way of keeping this home from experiencing more costly damage due to a lack of maintenance, Caldwell’s Roofing has scheduled a roofing maintenance schedule with the homeowner. At $65/visit, Caldwell’s Roofing blows off the roof as well as the surrounding decks and driveway/sidewalk, to keep everything in good shape. This will not only extend the life of the roof, but it also keeps everything clean and tidy.
Because the roof is greater than a 4:12 slope (it’s a “switch-pitch” with slopes of 5:12 in some places, and 8:12 in other places), Caldwell’s Roofing follows OSHA’s requirement to be harnessed while performing work (even the maintenance work). 9 out of 10 roofers will scoff at such a notion, but Caldwell’s Roofing installed permanent D-minus™ anchor points on the roof to enable their routine maintenance schedule. The workers simply don harnesses and attach to the D-Minus™ anchor points before beginning the work of blowing the roof off, and they are ensured of safety should anyone ever slip or lose their footing. It takes practically no more time to do that, and it could save a life.
Close-Up of a D-Minus™ Anchor Point, OSHA-Rated to 5,000 lbs
D-Minus™ anchor points can be obtained from www.SuperAnchor.com. Caldwell’s Roofing loves the D-minus™ anchor points. They’re relatively inexpensive (some $10/piece), are OSHA-approved, are easy-to-install with 6 provided spiral-shank nails, have a Butyl strip on the back to permanently waterproof the anchor (so it won’t leak down the line), can be permanently installed, can be tucked under a shingle (or, for dimensional shingles, under a “dragontooth” tab) where most of the anchor is “hidden” from view, and they can even be painted (check this before doing it) beforehand to match the color of the roof (to blend in even better). You do have to hit with a hammer to find the location of a rafter, as the anchor point is only rated for 5,000 lbs when it’s in a rafter (and yes, you really need the 5,000 lbs, as you can generate many times your own weight in a free-fall situation, which anchor points are meant to arrest). If plumbers and HVAC guys can have all manner of ugly penetrations through the roof, why can’t roofers leave a few tasteful D-minus™ anchor points to ensure the safety of themselves and future workers? It just makes sense.
Multiple D-Minus™ Anchor Points, Spaced at OSHA-Approved Max Interval of 12′
So, here’s a before and after of the roof we’ve been discussing. We loved the modern style the architect drew up for this house. What do you think of it?
Residential Roofing Photos: Illustration of Importance of Roof Maintenance
