According to roof repair contractors, installing new shingles over the old ones comes with its benefits:
- Saves you time
- Saves you the laborious roof removal step
- Saves you money
While this is the case, you should avoid installing the new roof over the old one. This is due to the many dangers that come with it. These dangers include:
They don’t do a good job at bridging over gaps
One thing you should know is that shingles are designed for flat surfaces. When the roofers are placing the new pieces over the old ones they have problems as they are unable to maintain the same step-ups between the courses.
If the old shingles are cupped, curled or have any other issues, the defects tend to translate through to the new layer.
For you to prevent this from coming about, many roofers recommend that you use laminated or dimensional shingles for re-roofs. This is because they tend to be thicker than the standard shingles. They also tend to have a staggered edge profile that comes in handy at hiding dips or high spots in the old roofing.
You can’t undertake proper roof inspection
Before you install the new roof, it’s recommended that you thoroughly inspect the roof for any imperfections that might be there and fix them. Since you don’t remove the old roof, you are unable to properly inspect the roof.
The few good roofers perform a careful “walking” inspection for the spongy areas and other problems that the roof might be having. They go ahead and make localized repairs before they re-roof.
The not-so-good roofers, on the other hand, don’t give attention to the roof. They simply install the new roof which is dangerous as the roof might come down any time.
You can’t replace the building paper
The building paper that is laid between the roof sheathing and shingles prevents water from getting under the shingles. When the paper gets old and deteriorated, it can’t protect the roof deck from the water. For you to inspect the paper and replace it if having issues, you have to remove the old shingles.
When you are placing the new shingles over the old ones, you can’t do this. This means that you can’t replace the underlayment even if it’s damaged. This puts your roof at a disadvantage.
In the short term, placing the new roof over the old one may seem cheap and convenient but in real sense, it’s expensive in the long run. Since you aren’t fixing the problems that are already there, the problems get worse over time, which can be expensive to fix in the future.
You tend to add a lot of weight
Roofing shingles are heavy. When you add two layers of it you make the roof too heavy. If the house didn’t have a strong foundation, it will most likely come down.
For you to prevent accidents as you are placing the new shingles, you should ask a professional to inspect the house’s foundation and give a recommendation as to whether the foundation can handle the extra weight.
If the house isn’t strong enough, you should avoid risking it and remove the old roof entirely before you place the new one.
You always have warranty issues
Most companies give warranties on their shingles, but when you install the new pieces over the old ones, you always run into problems with the companies. This is because the pieces aren’t designed to be installed the way you are installing them.
For you to avoid miscommunication, later on, you should check with the roofing material manufacturers about the requirements. You also should address any warranty concerns you might be having.
The local codes might not allow it
Sometimes your house’s foundation might be able to take the extra weight and the roofing companies might not have problems with you installing two layers of shingles, but the local codes might not allow it.
In most cases, areas that experience heavy hailstorms don’t allow two layers as the practice tends to put you and your family at great risk.
It’s obvious that installing two layers of roofing materials isn’t a wise move. However, if you feel that it’s the right choice for you, you should go ahead and do it. You only need to ensure that the roofing is done by expert roof repair companies Greenwich.