Is Roofing Over Existing Roof a Good Idea?

Are you thinking about selling your “starter” home, refreshing the look of your home, or fixing up a rental? Replacing the whole roof might seem a bit aggressive if the existing roof is still in relatively good shape. Reroofing or an overlay is an option, but is roofing over an existing roof a good idea?

What is overlay or reroofing? It’s when you put roofing material over existing material to instantly give your home a new look or to refresh the roofing system on your home. This is a cheaper option than completely tearing off the old roof, at least in the short term. So it can be a popular choice when it comes to a rental property or when you’re preparing to sell.

Can You Put Shingles Over Shingles?

If the existing roof is still in good condition, with no missing shingles and a few years of service left, an overlay is certainly an option. You are a little limited, however, if you want to put new shingles over an existing roof because of the materials. Putting composite shingles on your roof over asphalt shingles or three-tab shingles, you should be able to re-roof your home.

But if you want to mix and match materials, you will run into some issues because of the differences in installation techniques. For example, installing new shingles over cedar shakes, metal roofing, or slate is an exercise in frustration and will do more harm than good.

So can you put shingles on top of other shingles? Yes, but you have to thoroughly inspect the existing roof first. You don’t want to be covering any problem areas, such as weak spots in the roof structure or where there are missing shingles. These problems aren’t solved by just adding an additional roofing layer–they’re just hidden.

In some cases, build codes may limit reroofing, especially if weight is a concern. The structure of your roof may only be rated for a certain amount of weight. Adding a whole other layer of shingles may weaken the structure and put your home, you, and your family in danger. Check with home inspectors to see if this is a viable choice.

Is Roofing over an Existing Roof a Good Idea?

Even though it may seem like a cheaper, faster option, reroofing your home is rarely the best option for your home. Along with covering up potential issues, adding more weight to your home, and limited choices, at some point in the future you’ll be faced with the same decision.

Because most roofing companies won’t recommend–or even suggest–three layers of shingles on your roof, you’ll be faced with twice as much debris when you eventually replace multiple-layer roofs. That will cost more money, both in labor and dumping fees, and make the roofing job take that much longer.

So while there are times when an overlay may sound like a good idea, and conditions are conducive to this direction, it’s not much of a solution for the long haul. Additionally, you won’t want to add shingles over damaged shingles or as part of a partial roof replacement.

Your roof will have an uneven appearance and you’re still just covering the issue. At this point, you’re just better off installing a new roof. Depending on which materials you choose for your new roof, you may not have to worry about it for as long as you own your home.

Work with experienced roofing professionals

Warner Roofing and Construction has been performing new construction roof installations, tear-offs, replacements, and re-roofing damaged roofs for nearly three decades. We can also investigate what’s going on under the roof to see if there are any issues with the trusses holding everything up.

Have questions about your roof, looking for an upgrade as part of a whole-home remodel, or are even interested in skylights or solar tubes? We’re the Vancouver roofing contractor you’re looking for. Let us know what you’re thinking about doing and we’ll see how we can help.

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Roof shingles being replace on a home to illustrate how often should you reshingle your roof.A man looking out an open skylight to illustrate Should I Replace Skylights When Reroofing and installing a skylight.