The StoneMark Company: Unraveling the Truth About Installing New Shingles Over Old Ones
The StoneMark Company: Unraveling the Truth About Installing New Shingles Over Old Ones
Understanding the Need for Roof Replacement
There can be a multitude of reasons for replacing your roof, ranging from persistent leaks to age-related wear and tear. Some homeowners might consider installing new shingles over old ones as a cost-effective solution. However, while this approach may seem convenient and budget-friendly initially, it could lead to several complications down the line.
Cost Implications: A Short-Term Gain with Long-Term Pain?
Yes, roofing over existing shingles can save you money upfront by eliminating the labor cost associated with removing old shingles and disposing of them. But, that's only a temporary reprieve. The added layer of shingles increases the weight your roof must bear. If your home's structure isn't designed for this additional load, it could lead to sagging and instability.
Moreover, the newly added shingles tend to have a shorter lifespan than the original ones due to increased vulnerability to damage and wear. This vulnerability is exacerbated in areas prone to severe weather conditions like hailstorms. Also, shingles installed over existing ones lack the firm hold achieved when nailed directly to the sheathing, leading to potential blow-offs.
Convenience vs. Long-Term Performance
While homeowners may be tempted to cut costs by laying new shingles over old ones, it's crucial to understand the long-term implications. The new layer of shingles will likely be less effective in protecting your home from moisture. Any existing dark algae or moss growth on the old shingles gets trapped under the new layer, accelerating their degradation.
In cases where the older shingles are still in good condition and aren't leaking or infested with pests, re-shingling might seem more appealing than a complete tear-off and re-roof. However, keep in mind that most regions only allow two layers of shingles before necessitating a complete tear-off and re-roof. Overlaying new shingles can also void the manufacturer's warranty and potentially lead to roof instability.
Waterproofing Concerns
Overlaying new shingles can trap moisture underneath, leading to rot and other roofing issues in the future. It also reduces the lifespan of the new shingles. Moreover, this practice often voids the shingle manufacturer's warranty – a significant concern should you decide to sell your property later. Furthermore, laying a new layer of shingles creates an uneven surface that's challenging to seal properly, forming gaps that collect water or ice and damage the underlying roofing material.
Insulation and Structural Integrity
While overlaying shingles can offer minor additional insulation, it pales in comparison to what a complete re-roof would provide. If the original shingles are leaking or damaged, they'll likely continue to leak through both shingle layers into your attic and home, exacerbating any existing damage to the roof decking and underlayment.
Shingles are designed for flat surfaces, so installing them over humps, dips, or other irregularities in the roof sheathing can lead to problems. Additionally, any defects in the original shingles, such as blistering or curling, will show through the second layer, potentially causing leaks, wood rot, and algae growth, leading to costly repairs.
The StoneMark Company: Unraveling the Truth About Installing New Shingles Over Old Ones Understanding the Need for Roof Replacement There can be a multitude of reasons for replacing your roof, ranging from persistent leaks to age-related wear and tear. Some homeowners might consider installing new shingles over old ones as a cost-effective solution. However, while…