If you have properly maintained and cared for your roof, the average lifespan of asphalt shingles should be approximately 20 to 40 years. Over time, you'll find that some shingles here and there will begin to show signs of wear. To avoid compromising the underlying roofing structure and to avoid having to deal with extensive water damage later on, your best bet may be to replace all of the shingles. If this is the case, you have two options. You can either tear off the existing layer before installing the new shingles or you can re-roof over the existing layer. Here are 3 factors that will determine whether or not the latter is a possibility.
Whether the Existing Shingles are Smooth or Curled
In order to re-roof the asphalt shingles without having to tear anything off, the new layer you install must be able to perfectly fit over the existing layer. This means that the old asphalt shingles must still be in relatively good condition. While the old shingles can have cracks or holes in them, they cannot be warped in shape. If they are curled, it will be impossible for the roofing contractors to install a new layer of asphalt shingles over the old ones.
Condition of the Flashing
The flashing underneath the shingles will also need to be evaluated. If the flashing is not in good condition, the old asphalt shingles will need to be torn off in order for the roofing contractors to be able to easily access the flashing underneath for repairs or replacements. The roofing contractor will want to take a close look at the condition of the flashing to determine if it is still intact or if there are any cracks present. You can only re-roof your roof if the flashing is in good condition.
Weight Capacity Supported by the Underlying Roof Structure
Even if the shingles allow for re-roofing and the rest of the roofing structure is in good condition, you might still have to tear off the existing shingles if the underlying roofing structure simply cannot support the added weight. The roofing contractors will have to take a look at the blueprint of your home to determine whether there are any weight limitations that they need to be wary of. They will need to compute the current weight load applied to the roofing structure to determine whether an extra layer of shingles will compromise the structural integrity of the underlying support.
If your roof fits all the requirements needed to allow for re-roofing, you should highly consider re-roofing your shingle roof instead of tearing the existing layer of shingles off. Re-roofing over the shingles will be much more efficient. It will also require less labor without compromising the integrity and quality of the finished results.
Do you know how to tell if you have problems with your flashing, loose shingles, or damaged tar pitch? Well, I didn't either until I experienced some of those issues on my own. One day, I realized that my roof was leaking and that I needed to find a solution fast. After contacting a professional roofing company, they were able to solve my troubles and teach me the signs of trouble. I want you to avoid the same types of hassles, which is why my blog is filled to the brim with information about roofing and home ownership. You never know, these tips could really come in handy!