Fiber cement can go up to 25 years and the thicker asphalt can give you about 30 years.
How long does a second layer roof last.
However there are premium brands that can serve you diligently for 50 years.
When replacing your roof it s usually a good idea to remove the original layer of roof shingles but only if you intend to live in the home for most of the life of the new roof.
The second layer of shingles will trap heat which can result in the decomposition of both roof layers.
The shingles likely won t last as long so the job could actually end up costing you more in the long run.
This is especially true if there is huge snowfall.
Most homes have asphalt or composite shingle roofing which normally last about 20 years.
That second layer of shingles won t last as long.
This will force you to replace your roof earlier than expected.
Cedar shake can also go for about three decades.
In fact the extra layer can reduce your roof s lifespan by up to 40.
You are correct that second layers typically don t last as long as single layers.
And shingles have started to separate.
It will shorten the lifespan of your roof.
With proper installation you can expect a 25 to 40 years lifespan from a ribbed metal roof with exposed fasteners.
The shingles likely won t last as long so.
If there are any pros to overlaying a roof it s saving a little bit of money.
Installed correctly a new roof will last at least 15 years but the exact lifespan depends on the material.
Asphalt roof shingles remain waterproof until they dry out.
A ribbed metal panel roofing system featuring concealed fasteners will offer a longer lifespan ranging from 30 to 50 years depending on the environment.
Adds weight you re literally adding another roof to the top of your home so if your home is older or is not structurally sound you may not even be able to complete this type of roof job.
But because of the amount of prep work involved in overlaying a roof properly any savings are usually modest maybe 25 percent compared to a new roof.
I don t know if a precise formula like that exists but the second layer does have less firm foundation than the first and it would be logical to expect shorter life span.
You could be adding weight to your roof with a second layer that your house cannot handle.
Here learn which roofing lasts the longest.
But because of the amount of prep work involved in overlaying a roof properly any savings are usually modest maybe 25 percent compared to a new roof.
I think you ve got a good life out of it.