There are several reasons to have a shingle roof replacement. One reason is one or several of the asphalt shingles are damaged because of a storm or high wind or aging. This type of shingle roof replacement is not replacing the entire roof but a small portion of it.
The other reason for a shingle roof replacement is when the roof has aged and is no longer a functioning roof. In this case, the entire roof will have to be replaced.
Asphalt is not the only material a roof shingle is made from. There are metal shingles, wood shingles, recycled rubber shingles and slate shingles. And each of these shingles has their pros and cons and has different price points.
For this discussion we will use asphalt shingles which are a very common roofing shingle used throughout the United States.
If you see that some of your asphalt roof shingles are coming off or are splitting or breaking or even curling at the edges you can repair or replace them your self. Or you can call a local roofing contractor. Either way the process will be the same. But one advantage to calling a roofing contractor is that they can check out the rest of the roof to make sure it does not need a whole house roof replacement.
The fact that they will be walking around on your roof and you do not have to take that risk. If there are broken shinglees then you will need to remove them and then replace them by sliding them up into the area you took them out of. If they are curling up you will need to glue them back down. If they are cracking again you will have to replace the cracked shingles. If some have blown off then you will have to replace them with new shingles.
If you require an entirely new roof then unless you are going to do it your self you will need to get some estimates from local roofing contractors. Typically, most people will decide to replace an old roof with a like roof. Sometimes they may upgrade the shingles or even change the color but generally if there is an asphalt shingle roof they will not opt for a metal roof even though a metal roof can cover asphalt shingle.
Getting a shingle roof replacement is fairly easy, its repaired to like new condition or replaced with a new home roof.