roofing contractor installing shingles

3 Reasons to Tear Off Rather Than Overlay Your Roof

When replacing your roof, you can either choose an overlay, where your roofing contractor places another layer of shingles over your current shingles, or have the existing roof torn off before putting on the new layer. As you can no doubt guess, an overlay is less work for your contractor, which means it can save you money in the short term.

However, it’s not quite as simple as it sounds; you need to think through all the ramifications before choosing between these two options. Although building codes will often allow two or sometimes three layers of shingles, a tear-off is often the better investment. Here are three reasons why.

1. Shingle Sandwiches Can Cause or Exacerbate Roof Problems

If you have a new layer of shingles installed over the old ones, you’re effectively sandwiching your old, worn-out, damaged shingles between the new shingles and the roof deck. This can cause or exacerbate a variety of problems; if there was undetected water damage to the roofing deck, for example, it will continue to worsen until tear-off occurs.

In addition, any water that had gotten past your failing shingles will remain trapped there against the roof deck, which can allow new water damage to occur. And the additional layer of black asphalt shingles helps trap heat more efficiently as well, which can mean the new shingles wear out faster from heat damage and need to be replaced even sooner.

2. Savings Now Can Mean More Money Spent Later

In addition to potentially increasing the money you spend on repairs, the effects of an overlay can balance out the initial savings in other ways at well. For example, the more layers your roofing contractor has to tear off your roof, the more it’ll cost you in labor. This means that tearing off two layers will make your next roof replacement cost more than a one-layer replacement costs now.

And unless you’re in a true financial emergency right now, putting off part of the expense is probably not a good excuse to wait. After all, who knows what will happen in the meantime? You could be worse off financially next time your roof gives out, and the larger expense will be even more difficult to save up for.

3. More Weight Places Strain on Structural Support

Although it may not directly damage your roof, the extra weight of another layer of shingles can place more strain on your home’s structural support. This can be especially dangerous if you live in a cold climate where your roof needs to be able to carry as much snow load as possible.

The more weight your roof is already carrying, the less snow it will be able to reliably support during the winter. Be sure you know how much snow your roof can support and check to see if another layer of shingles would reduce the roof below the capability it needs for safety.

These three points demonstrate how a roof overlay can have a higher cost than you realize, both in more money spent later and in potential roof damage and shortened shingle lifespan. While you can save money in the short term with an overlay, you won’t necessarily be saving money overall, and you could be setting yourself up for water damage problems.

Be sure to consider these things when you’re making the decision whether or not to tear off your current roof before replacement. Whether you need a new roof, a roof damage assessment to decide between repair and replacement, or other roofing services, SUNVEK is ready to help. Get in touch through our website to get your free estimate.

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