Damage to your roof can occur suddenly or grow gradually over time. It could take the form of slow rot in the plywood and gradual deterioration of the shingles, or be much more drastic in the form of storm damage or sudden impacts. In any case, working on your roof can be an expensive task.
Repairing your roof is generally the cheaper option. Unless the damage is extensive, you will be better off pulling off some shingles and replacing them. It is also quite possible to lay a new layer of shingles on top of an older layer, which saves the time and hassle of tearing out the older layer. This is a common practice, and many homes have up to five or six layers of shingles piled on top of them. [Editor’s Note: Although you may find more, you should never add another layer if you already have three and most professionals rip off the previous layer even if there is only one on it. Because it allows you to assess the layer under it to determine its condition and multiple layers can become extremely heavy.]
Adding a new layer of shingles to your roof, whether or not you tear the older layers off, will help to increase the value of your home. A new roof is likely to be installed professionally, and will look great and work well if it is done correctly. Unfortunately, in the process of removing the old shingles, you may come across more extensive damage than you realized. In these cases and in those where the damage was extensive to begin with, you will be better off replacing the entire roof.
Replacing your roof is quite expensive, but in some cases, it is necessary. It will also add significant value to your home when it is complete, because it guarantees to the homebuyer that the roof has no hidden damage.
If your roof is made out of concrete tiles or slate, you can expect it to be very expensive to replace. The tiles themselves are virtually indestructible from the weather, but a falling tree can still damage your roof. The most common problem with these roofs is structural issues with the surface the shingles sit on. Metal roofs have similar issues, but do not have quite the same weight issue that stone encounters. In any case, the older your roof is, the more likely it will need to be replaced due to some underlying issues. The more durable the shingles are, the harder these issues are to spot.
Weather is an important factor when deciding whether to repair or replace your roof. Homes in areas with high moisture exposure, especially those in colder climates with plenty of snow and ice, will find their roofs last shorter periods of time than drier climates. However, moisture is not the only issue. ON the other end of the spectrum, constant heat and sun exposure can also deteriorate shingles, especially asphalt shingles. Wind can also lift and/or tear shingles and allow moisture under them, which can cause rotting underneath and plugged gutters can allow water to back up under the shingles on the edges also resulting in rot.
When deciding whether to repair or replace your roof, it is best to call in a professional roofer for an analysis of the current roof. If you are looking to save money, they may recommend an overlay, where a new layer of shingles is added on top of the current layer. In other cases, spot repairs may be possible. Repairs can extend the life of your roof a few years and are the least expensive solution in the short run but in the long run the oof will still need to be replaced, while, overlays can add twenty or more years to the life of your roof.
If the contractor recommends a full replacement, it is best to get it done, even if the cost looks high. The initial price is high, but if you let it go, it will grow worse. The last thing you want is for your roof to collapse under the weight of shingles and rotted wood. But prices between contractors can vary widely so it is best to get at least two separate bids and preferably three. Also be wary of contractors knocking on your door and offering services, they may be con-artists or just poor craftsman. Generally, those who perform quality work don’t need to knock on doors, although there may be exceptions when the economy is in very bad shape.