There are generally two options when installing a new roof.
Roof tear off or overlay.
The tear off method is self explanatory your roofing company will tear off the existing roof and replace it with a new one.
With an overlay roof you actually keep your existing roof in place and put another one on top of it.
It s the most established way of installing a new roof but it s not the only way.
Apply roofing cement slide the flashing over the pipe and push so it lies flat on the roof.
However the truth is so many variables have to be just right in order to make it work that it s much more likely to cost you money in the end.
In general it is not a good roofing practice to overlay a traditional asphalt shingle roof versus a complete tear off and replacement with a new roof for the very reason you stated.
When the roofing company you hire tears off your existing roof and then puts on an entirely new roof.
If you don t take your roof down to the sheathing you will never know if you have proper underlayment or are experiencing sheathing rot or ice or water damage.
Tear off the old one and start from scratch or overlay a new roof one on top of the old one.
You can t examine the decking to determine if there is any damage that needs repaired.
It takes a lot more labor to completely remove all the existing roofing material and then replace all the layers removed.
Depending on the width of the pipe you may need to tear away a segment or two of the rubber boot.
The tear off method is exactly what it sounds like.
An overlay roof occurs when keep your existing roof as is choosing instead to shingle on top of it.
Which method is best for you depends on your priorities and future plans so knowing the costs and benefits can help you make this important decision.
Higher costs on average a tearoff roofing job costs around 25 percent more than an overlay.
There are pros and cons to both approaches.
Overlays save on time labor and disposal costs.
In a nutshell however roof tear off method is much better compared to overlay.
Which is best for your home.
This is because you basically get a better quality the better value of the roof and overall it makes your roof last much longer.
The old roofing also has to be disposed of properly which adds to the cost.
Roofing tear off or overlay the question often comes up about whether an existing composition shingle roof should be torn off or if an overlay or recover is possible.