Roof Over vs. Roof Replacement
 

Which did you do? Comments? (stay on topic!) I'm a couple/few years away, but thinking on it. Good, short read.

When You Can And Cannot Reroof Over Existing Shingles

I would never install shingles over existing shingles. It adds weight to your roof, can cause leaks, and it prevents you from correcting sheathing issues that may be present under the existing shingles.

First I would get a review of the design of your roof, and your trusses, especially if this is an older house. Back up north I was specifically told to NOT do roof over, sorry I do not recall the reason, and there was very little cost difference. I think the concern was that IF there was any damage to the roof or its supporting structure you would not know it since the old roof was not removed. You may also want to consult your insurance carrier, as they may have specific requirements to continue coverage.

That would be the first step I would do.

Generally, it's ok to roof over an existing roof of one layer of shingles.

That said, it's far less common in Florida, than most other states. I'm not a roofer, but from what I understand, it's nearly impossible to meet FL roofing regulations without removing the existing roof (unless it's only a couple of years old).

In cooler climates a roof over is commonly done. In hot sunny climates older shingles often buckle and curl up and it’s not advisable to put new shingles over them. As previously mentioned, you don’t want to give your homeowners insurance carrier a reason to cancel your policy.

I was told by manufacturer that it isn't recommended to install another layer of shingles over architectural shingles.

Agree. Also a suggestion. When we redid the roof for our old Maine summer home I had the ENTIRE roof sheathing covered in “ice & water shield” before shingles were applied. Will never leak and roof is sealed. Was actually the brand IKO but same thing. Of course need to insure that all roof sheathing was sound before applying fabric

Tear off and reroof. Best and longest lasting.

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Appling second layer of roofing
 

I was at my friend's home this week when he received a quote for a new roof. He asked about applying the new roof over the existing shingles. The roofing rep. said that the state of Florida does not allow this any longer. The law was changed a year or two ago.

I have seen many roofs replaced here in The Villages. The old roof is removed very quickly in less than half a day. The labor savings is minimal if that is what you are trying to achieve.

Roof over roof?
 

I would think a roof has to breathe, eh? Adding layers will hinder the escape of heat....at todays temp in tv i'd say that would be a big deal....

Did the roofing rep cite the Florida law? I don't recommend two layers of shingles, but I cannot find any Florida law that prohibits it. Contractors will often tell you things verbally that are not true.

2 big issues.. I've heard insurance companies won't insure a roof over roof. And even though your article says the mfgr will warrent a roof over roof, I believe many won't. No smooth surface to apply new shingles. I'd stay away from it.

I'd be interested in what the original poster finds with additional research

Doesn't seem to matter
 

Down here it doesn't really seem to matter how long a roof lasts. The insurance company will determine that - not dependent on how good your roof is, just how old(new) it is.

The original poster (me) is a lazy bum. My plan is to wait until a few months before I need a roof, then contact my insurance company to get their take on it. If it's NOT an issue, I'll talk to a few roofers later for quotes and pro/con of the options. I just wanted to get a few perspectives from all the smart folks who read this forum! I'd probably get a roof replacement, but I like to know options.