Is Installing A New Roof Over An Old One OK?

chalk question mark on chalk board
Has someone suggested installing a new roof over your old one?

The Big Question.

There is a question that appears every so often in the roofing industry, that needs addressed once and for all. The question being, “Should I install a new roof over my old one, or is that a terrible idea?”. Most people don’t come to this question on their own. Usually, less than honest roofing contractors are responsible for planting this question in the minds of unwitting homeowners.

The Common Opinion Among Decent Roofing Contractors.

Many roofing professionals frown upon this option. So much so, that no smart roofing company is going to warranty this service, if they are willing to even do the job. While the customer may save money up front, laying a new roof over an old one, they will most likely pay for it in the long run.

Side Tip.

If you are buying a preowned house, make sure there aren’t 2 or more layers of shingles. A deceptive trick to watch out for, by the less than decent folk, in the house selling game. Be it homeowner, or house flipper. You never know who will do this, so it pays to check no matter what.

To Be Blunt.

Quote about cutting corners across faded background of a padlock on a green fence.
We Don’t Cut Corners In Our Business.

Our roofing company, Craven Roofing & Construction, Inc., does not perform this service at all. Not only would the liability be to great to us, but more importantly, the disservice to the customer is one we simply won’t participate in.

Even If They Can’t Afford Anything More?

Yes. Even if our customers can’t afford a full roof replacement, and insurance is not covering it for them — we do not put new roofs over old ones. Doing so isn’t heartless either, there is sound reason behind this. When you put a new roof over an old one you set several things in motion that you can’t see.

What Could Happen?

edited stock photo crop, man shrugging shoulders.
“How bad could it really be?” – There is a reason that question was left in 70’s TV.

Firstly, you are locking in all the moisture that has leaked in already, which can lead to mold and mildew build up in your attic.

Additionally, the second layer will weigh several thousand pounds. This will add a great deal of stress to the existing roofing structure, most likely causing additional leak problems. Your roof wasn’t built to hold that much weight. It’s made of wood in their folks, not iron.

But Wait, There’s More!


The big red flag in the situation still needs to be addressed. When a new roof is installed, it is applied to wooden decking, which is flat, and smooth (Similar to the backs of shingles, and underlayment material). When you apply a new roof over an old, the application surface is anything but flat.

Moreover, it is extremely rough due to the asphalt it is made of, which pierces, scuffs, and scratches at the new layer you are applying, under it’s own weight. This causes leaks, which feed into the old leaks, and cause more water damage to your roof and attic.

You Will Pay Significantly More Down The Road To Fix It.

Now who is going to fix this roof when it starts falling apart under its own weight? It’s a 2 layer nightmare that no roofing contractor will touch unless you agree to all that it comes with. They usually won’t repair it simply because it is a liability. So that leaves you with full replacement.

Which includes, paying for, not one, but two roof removal charges. If they are taking off two roofs, they are going to charge you for it twice. Simple math.

So, to save a penny today, will spend tomorrow’s dollar? We wouldn’t, and we don’t.

We Hope You Found This Informative.

In most of the subjects that we cover in our blog, we defend and inform the homeowner in regards to roofing. This time, to ensure DFW homeowners aren’t making mistakes that will haunt them in the future, in regards to their roofs, we took the big brother approach and told it like it is, bluntly.

If you’d like to learn more about the DFW roofing industry, as it pertains to homeowners, subscribe to our blog!

7 thoughts on “Is Installing A New Roof Over An Old One OK?”

  1. My son pointed out to me yesterday that there were a few patches on my roof where the shingles have been stripped off. It’s getting really close to the time when a new roof is needed in order for us to feel safe from storms. I appreciate you saying that it’s really not a good idea to put a new roof over an older one because of the pressure it will put on the structure of the house.

  2. It’s good to know that you will save a lot more money in the long run by just replacing the roof. If you put the new roof over the old one you will run into lots of problems. My roof is looking shabby lately so I think it’s time to find a company that can replace it for me.

  3. My uncle’s house is getting pretty old and really needs some essential repairs done in order to pass some inspections. I think that the first thing that needs to be done is installing a new roof because the old one is barely functioning. It’s good to know that we can’t just build over the old roof because this puts way too much pressure on the support beams of the home.

  4. That makes sense that having a roof installed over an old one would make it really heavy. I would think that if you used a heavier material like slate or something, that it would be even heavier. Hopefully removing the old roof would make it much less likely to collapse.

  5. It makes a lot of sense that the roof would be way too heavy if you just put a new roof over the old one. My partner and I are buying a home that has some things that need to be fixed up. Putting on a new roof is probably the first thing we need to do so that everything inside is safe from storms and other damages.

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