The Age Old Question When You’re Preparing to Replace Your Roof...
“Do we tear the old one off or just re-roof over the top of it?”
Every homeowner sooner or later faces the daunting task of needing to have the roof on their home replaced. And rest assured, the million-dollar question is “Do we have to tear off the old roof or can we just put shingles over the top of it?”
If you are in the middle of doing your due diligence for this particular task at hand, the following information will help you understand if your home is even a candidate for a re-roof, or if it will require a tear off.
How many layers of shingles are currently on your home?
Once upon a time some communities and municipalities actually allowed three layers of shingles to be put on a home. Today, those communities are very few and far between with most cities only allowing two layers of shingles on a roof.
If your home currently has more than one layer of shingles, tear off will more than likely be required.
There is only one layer of shingles on my home, now can I get a re-roof?
Now that you’ve determined there is only one layer on your home, let’s visit the next set of qualifying questions…
Approximately how old are shingles on your home and more importantly, how do they look?
The typical life expectancy of an average shingled roof ranges anywhere from 17-27 years, depending on the type of shingle used and the region of the country you reside.
As a roof ages, some of the most common signs are granule loss and the corners of the shingles starting to curl.
It is important to keep in mind the flatter the surface of the current roof, the flatter the shingles over the top will lay as they are installed, resulting in an aesthetically pleasing re-roof.
Has your current roof shown any signs of leaking?
The answer to this question is imperative when determining which route to go. Most (if not all) reputable contractors will not even consider installing a second layer over an existing roof that has shown signs of leaking and here’s why…
Most roof leaks are due to parts of the roof system other than just the shingles! Parts of the roof system such as roof to wall flashings, roof vents, skylights, and vent flashings, not to mention Mother Nature throwing in her two cents with ice damming, ice back up, wind driven rain and interior condensation!
You see, re-roofs generally consist of installing shingles over shingles….period. Whereas all the pieces and parts mentioned above are either below the shingles or integrated into the first layer of shingles and are not accessible if the current roof is not being removed.
What type of shingles are currently on your home now, architectural / dimensional or 3-tab?
The older, traditional 3-tab shingles are only one ply and lay flatter by design than the two-ply architectural/dimensional shingle which appears as a more rugged 3-D look, hence the moniker “dimensional.”
While it may be possible to re-roof over an architectural/dimensional shingle, the finished re-roof product over this type of roof may not be as pleasing to the eye as a re-roof over a traditional 3-tab shingle.
Ok, So Let Me Just Review My Checklist…
I only have one layer of shingles on my home – CHECK!
The current shingles are still laying flat; I don’t see a lot of curling – CHECK!
My roof has never shown any signs of leaking – CHECK!
My current roof is a 3-tab shingle, not an architectural/dimensional shingle – CHECK!
Now Can I Get a Re-Roof?
The quick answer is YES! But before you make that final decision, please read on for just another minute or two as we discuss the general pros and cons of re-roof vs. tear off.
As mentioned above, a re-roof is generally defined as installing shingles over shingles…..nothing more, nothing less.
Less expensive - Less labor, less material (no underlayment, ice guard, etc.), low debris removal costs.
Less Mess - Unlike a tear–off (which is the equivalent to open heart surgery on a house), a re-roof is a considerably “cleaner” process, not only around the yard, but in attic spaces as well.
Less inconvenience - The contractor shouldn’t need to be on your property nearly as long for a re-roof as opposed to a tear–off.
No visual inspection of some of the most important parts of the roof system, including, but not limited to, roof to wall flashings and the roof deck (the actual wood under the shingles and underlayment).
Eliminates the option to replace ice & water shield to protect against ice damming and ice backup, new underlayment (felt paper), roof to wall flashings and skylight flashings
A tear-off is generally defined as removing the entire existing roof system down to the wood deck and installing a roof new system.
Visual inspection of some of the most important parts of the roof system including roof to wall flashings and the roof deck (the actual wood under the shingles and underlayment).
Replacement of the following products: Ice & water shield to protect against ice damming and ice backup, new underlayment (felt paper), roof to wall flashings & skylight flashings.
More expensive - More labor, more material (underlayment, ice guard, etc.), higher debris removal costs.
More mess - A tear–off (which is the equivalent to open heart surgery on a house), is a considerably messier process, not only around the yard, but in attic spaces as well.
More inconvenience - The contractor will more than likely need to be on your property a little longer for a tear-off as opposed to a re-roof.
While roof tear-offs are much more common and thorough, a re-roof is certainly an option under the right conditions and circumstances! https://www.angieslist.com/articles/pros-and-cons-new-roof-vs-overlay.htm