What is a roof overlay and how does it impact your new roof? A roof overlay is an outdated roofing method in which roofers would install new shingles on top of your old shingles.

Think of it this way -if you were to get new carpet, would you lay your new carpet over your existing carpet? No.

However, this actually used to be a method roofing companies would use back in the day, with many thinking it was a more efficient and durable way to add a new roof to your home. This process was referred to as an “overlay.”

While the model is significantly outdated, some still might use this method. Today, we will answer the question of what a roof overlay is and why it matters for your new roof replacement project.

What is a roof overlay in the first place?

A roof overlay sounds like a covering over your window or door, but that would actually be inaccurate.

When a roofing contractor completes a roofing overlay, they’re placing the new roof’s shingles over the existing shingles. Hence the name overlay; roofing contractors will lay new roofing materials over the existing roof.

This approach used to be expected and the understanding was that more shingles on your roof meant more protection. Also, roofing contractors had to charge more to remove old layers of shingles so it was also the cheaper option.

However, in today’s age, you won’t find many roofing companies that do an overlay, and you should always make sure to clarify this when you’re getting a new roof.

Pros and Cons to a Roof Overlay

Below you will find the pros and cons to a roof overlay. Let us clearly state that the pros are few and while we don’t want to make generalizations here at Legacy Roofing of Idaho, we do want to share that 99.9% of the time a overlay roof is not ideal.

Roof Overlay Pros

Cheaper option (more on this later)
Seen as quicker and more efficient
More layers

Roof Overlay Cons

Not as durable
The roof’s structure is not designed to hold the extra weight in some cases
Roofing over damaged shingles is not smart
You missed out on the inspection of the plywood decking that may need to be replaced
Long-term, it costs more
The roof approach isn’t that hard and only takes 1-2 hours longer
More is less. More layers do not mean your home is more protected. A roofing overlay can actually void a new roof warranty and make it hard to repair in the event of a leak or issue.

Replacing Your Old Roof with a tearoff

Below, you will see a picture of a brand-new asphalt shingle roof. Prior to installing these new shingles, we completed a tear-off of the existing shingles and underlayment.

A brand new roof in the 21st century should always be applied directly to the roof decking following this approach:

Remove existing shingles and roofing underlayment
Install new synthetic roof underlayment
Install new asphalt shingles with the proper amount of nails to have certified warranties from the shingle manufacturer
Enjoy your new roof

This process detailed below is the standard operating procedure for replacing your existing roof and the tear-off room method is a must. Most of the time, a solid roofing company can remove and replace a roof in one day.

What is Better Existing Roof Overlay or Roof Replacement?

While some may try to argue that a roof overlay is cheaper than a full-scale new roof replacement, the answer is that a roof replacement is better and less expensive.

For starters, a roof overlay has too many cons to deal with such as a greater chance of leaks, less durability, less warranty coverage, and your long-term costs increasing.

When it comes to resale value, your home will often recoup 70%-80% of your costs with a new roof, however, not with an overlay where this is actually not a good selling point. Most roofing companies charge extra if there happen to be two layers of shingles, but a normal one layer tear-off is included.

The winner is: Tear-off.

Tear Off: Longer Lasting & Better

One distinct advantage of a tear-off approach to a new roof is that it is actually less expensive and it is also longer lasting/more durable. You typically are not going to be asked if you want one or the other, but keep in mind that a reroof over your old roof is not the option you want to go with.

Pros and cons matter, and in this case the overlay process has too many cons to deal with.

Pros to a Complete Tear-off New Roof:

The best option is always to install a completely new roof (stripping the old roof off and adding new insulation and shingles).

Roof Overlay: An old method that is no longer used

To help you understand this method further, think of it as an old method that isn’t used any longer – or at least it shouldn’t be.

Roof tear-off factors in the price of your new roof and this cost is minor if it costs anything at all. Knowing this, some companies still may try to hedge the idea that you save money with a reroof overlay – but that isn’t true.

It was once thought an overlay was the better approach to savings, but now it is generally regarded as a lazy approach that is essentially adding more work and costs down the road. Also, when you need a new roof, why would you want to put your new roof on a worn-out roof?

See More: For a complete guide on roof costs, be sure to check out our post here.

Hiring a Roofing Contractor

When it comes to hiring a roofing contractor, here are the things you need to be mindful of in order:

Are they licensed, bonded, and insured?
What does their track record look like?
Talk about pricing and their process to installing a roof
Be sure they used the highest quality materials (think shingles)
Do they do a new layer over an existing layer, or do they tear off the old roof? This is a question we should always ask just to be safe!

In the event, a company only does overlay (this isn’t common) then we suggest putting that contractor to the side and finding a new one. You don’t want to compromise your roof’s structural integrity or the long-term health of your home!

Frequently Asked Roof Overlay Questions:

✅ See Also – Our Complete Roof FAQ

Is it cheaper to do a roof overlay?

At first, it might seem cheaper to do a roof overlay – put a new roof on top of an old roof – but it is not. The costs, later on, are way more and new roofs have the roof tear-off included already! It is not extra.

What is better a new roof or a roof overlay?

A roof overlay is when a new roof (layer of shingles) is applied over an existing roofing material. A new roof is when everything to the plywood decking is replaced – this is the best way to go. You don’t lay new carpet on your old carpet, just like you don’t lay a new roof on an old one!

What is a Roof Overlay? [And Why it Matters for Your New Roof]