Anytime you spot a missing shingle on your roof, the best thing to do is to call your trusted roofer for a quick roof repair. Acting on it immediately can prevent more expensive problems brought about by moisture penetration and water damage.
However, if this isn’t a one-off thing and you’re constantly calling a pro to replace blown-off shingles, there must be a serious problem. Why are your shingles getting blown off? Finding out what causes the shingle blow-offs can lead you to the root of the problem so your roofer can apply the appropriate fix.
Understanding Roof Blow-Off Protection
Good-quality shingles are not supposed to be blown off your roof. They’re not even supposed to move. They are rated for 110-130 mph winds, sometimes higher. So if there are severe gusts of wind blowing in your area, your home should remain protected.
A tornado or a hurricane is another story. But category 2-3 winds accompanied by moderate to major storms should not be able to blow off your shingles unless your roof is already damaged or old.
To keep shingles on your roof, they are nailed securely to the roof deck during roof installation. These wide-headed nails with sharply pointed short shanks are designed to be effective in keeping shingles steadfast without causing damage to the wood or ripping to the shingles.
Shingles that are used for a re-roofing project have adhesive strips that stick to the shingles underneath them. When this is done correctly, the shingles have a water-tight seal.
How Shingles Are Blown Off
There are several culprits behind shingle blow-offs. Most of these should be diagnosed by a professional roof inspector or roofing contractor.
1. Faulty Installation – Poor installation practices can lead to shingles that are not fastened properly, so it’s easy for the wind and a downpour to knock them off the roof. Shingles have a nailing strip where roofers are supposed to nail them. If nails are positioned above that strip, or too high on the shingle, they cannot hold the shingle well enough. This is the common reason when shingles are ripped off where they are nailed.
2. Roof Material Base Is Damaged – Your shingles may be fine and the installation is according to specifications. However, if the base where they are attached is compromised, it will not hold the shingles. Before long, your shingles will be blown off.
There are different types of material used in building the roof deck. Plywood sheathing, OSB board, corrugated metal, or some other material. The roof deck is where a roofer fastens a membrane layer or a roofing material during roof installation. However, if the deck is compromised by water damage, it will not have enough strength to keep shingles in place during windy and stormy weather.
3. Roof Is Due for Replacement – All materials have life spans, including asphalt shingles and other roof options. With asphalt shingles, you can expect your roof to last up to 10-15 years. This is a decent amount of time for a roof to survive with reasonable maintenance. The best shingles can perform for up to 20-25 years.
It’s different for every roof, however, because there are also different factors at play. For example, it’s hotter in some areas than in others. Likewise, it’s colder and wetter in some regions than in others. Homes located near trees receive more debris, and those near the coast are exposed to salty winds and showers. How you treat your roof may also be different from how others treat theirs (eg. how frequently your roof undergoes inspections and maintenance).
All things being equal if a roof is old and due for replacement, there is a higher likelihood of shingles being torn off by the weather and by debris impact.
4. Other Factors – It’s also possible for shingles to be blown off when the roof is new. Seal strips may not have properly set before the wind picked up. Shingles installed during winter weather, and those that have not received enough sun can also be affected immediately by the wind. The quality of your shingles is also crucial.
It takes up to a month and a couple more weeks for your roof to completely adhere and set under agreeable weather conditions. If shingles are blown off during this time, ask your roofing contractor to replace the missing or damaged shingles. A reputable roofing contractor might do this for free, especially if the weather is moderate.
You can save money by repairing your roof if some shingles are blown off. Your roofer will remove the damaged shingles and install new ones in their place.
Note that this is most effective if you don’t wait long before calling your roofer. Delaying shingle repair exposes your roof to water penetration. The longer you wait, the higher the likelihood of needing a full roof tear-off and replacement. Repairing immediately allows you to save money.
The problem with repairing is that new shingles often look different from the shingles you won’t be replaced because the latter has faded from exposure. If you don’t mind the “patched” look that may affect your home’s curb appeal, then this technique is the cost-efficient way to got.
If upon removing the damaged shingles, your roofer finds out that the roof deck and underlayment have been damaged, as well, the only safe course of action is to replace your roof entirely. Besides, if there are plenty of damaged and missing shingles, it’s highly likely that your roofing structure has already been affected by the exposure. The longer you wait to do something about it, the worse the damage will be.
Considerable damage to the roofing structure calls for a full replacement. There’s no point in replacing the missing shingles if the structure underneath is already rotting or starting to crumble.
In most areas, building codes will allow up to two layers of shingles. In some, this style of re-roofing is completely illegal. When you replace an entire roof, the cost is more significant if there are more layers of shingles than one. However, double or multiple layers of shingles often mean a complete tear-off is necessary when the roof is damaged or old.