Whenever there’s any issue with the roof, roofers often suggest replacements. However, given how expensive roof replacement can be, that’s easier said than done!
In such situations, homeowners often request roofers to install a new layer of shingles on top of the existing ones – aka roof layover work.
While this process can be done, it can be quite tricky. Your home needs to meet certain conditions to be eligible for it. You must also be aware of the advantages and limitations of overlay work.
So, if you’re interested in it, here’s everything you should know!
What is a Roof Overlay or Roof Layover?
Roof overlay refers to where new shingles are installed directly on top of the current roof (generally asphalt shingles). The previous layer is not torn off, and instead, your roof gets a second (and even a third) layer.
Experts usually go for this when the current roof is in good condition but needs a bit more protection. Sometimes, they also suggest it for improved aesthetics.
This is allowed only in specific conditions and where the building codes are complied with.
Note: “Roof overlay” is the common term generally used by roofing professionals. Homeowners casually use “roof layover” to refer to the same thing.
How Roof Overlay Works?
Here’s a short overview of how it’s undertaken:
- Roofing professionals investigate the roof deck and shingle condition.
- They check whether you need a permit and acquire it, complying with the local code.
- They replace any curled, missing, or damaged shingles for a smooth surface.
- They install a fresh underlayment for additional protection. This might be something like synthetic roofing paper.
- They install the new shingles over the existing ones using standard procedures and materials. If necessary, they adjust/reinstall the valleys, flashing, and edges to ensure proper waterproofing.
- They pay special attention to edges, vents, and chimneys to make sure there are no issues with airflow or sealing.
Pros of Roof Layover
More Affordable
Many suggest building a roof from scratch, but it’s easier said than done. In fact between roof overlay vs replacement, the most common reason homeowners choose the former is because it is inexpensive.
In the overlay, there’s no added expense for the removal and disposal of existing shingles. Roof overlay cost is around 20-40% less than what they’d have to pay for a complete replacement.
Quick Installation
Layovers are generally much faster than complete replacements. This is because there’s no additional tearing down and restoring everything. The roofer’s team can complete this within a few days, depending on the roof’s size and design.
Less Messy
Another significant pro of picking overlay is the lack of debris. If your home’s roof is completely torn off, there will be a lot of debris around your property. This can make your home dusty. Cleaning and restoring it into a comfortable space will need more effort, time, and money.
Minimal Noise
Tearing off an existing roof is quite a noisy feat. This can cause significant noise disruption, interfering with your neighborhood’s peaceful environment.
In the overlay, the noise is much less, which lets you stay at home (if you want) during the project. Otherwise, you can also rent a space nearby to stay until then.
However, in a complete replacement, it’s too noisy. You will not only have to relocate until the project is over but make sure you find somewhere far away so you can rest well.
Additional Protection
An extra layer of roofing over your current roof offers additional protection against the weather and can also provide extra insulation.
Short Life Span Boost
If you opt for a complete roof replacement (asphalt shingles), it will last around 20-30 years. On the other hand, if you go for an overlay, it can serve you for 10-15 years – which is almost half of what you might get for a replacement. Compared to the expenses, this is good enough.
Cons of Roof Layover
Extra Weight
Every home has a maximum weight capacity for its roof. For a roof heavier than the limit, the house structure would require some reinforcements.
Needless to say, shingles being heavy, even a single extra layer can increase the pressure on the roof structure significantly. If a house is old, it’s probably not designed to bear this extra load. This can lead to stress-related damage and sagging.
Unnoticed Existing and Future Damage
A layover can hide major existing damage, including water damage, mold, and rot, to go unnoticed. As the old shingles have not been removed, there’s no chance of inspecting any hidden issues beneath them. This can worsen the situation and lead to expensive repairs later on.
Furthermore, the roof becomes more susceptible to moisture trapping if the overlay is done over a wet area. If the locality experiences extreme heat, the gap between the two layers can absorb heat from the sun. This increases the chance of the shingles warping or curling.
Limited Future Repair
After an overlay, the chances of repairs are limited. In case of major issues, you may need to tear off both layers, fix the issue, and reinstall a roof. This means excess expenses in the event of damages.
Curb Appeal and Resale Issues
Overlay can make your roof look bulky, which can ruin its clean aesthetics, especially around the edges, and curb appeal. This again impacts your home’s resale value and marketability. Potential buyers may think the structure has hidden damages.
Warranty Issues
Several manufacturers offer a warranty on their shingles. However, if you go for an overlay, this warranty is voided.
Key Considerations Before Choosing a Roof Overlay
Local Building Codes
Before going for a roof overlay, consider whether the local building codes allow it. A reliable roofing contractor will be able to tell you so. They can even guide you to get the required permits to get an overlay if it’s possible.
Roof Condition
Next, you must focus on the roof’s condition.
If the existing roof has damage signs, such as wet spots, shingles curling or warping, or any other damage, a full replacement is a safer option.
If the existing roof is healthy and any mentioned damage sign isn’t visible, a layover is possible.
Roof Structure
If the roof is steep, there’s a high chance of an overlay to slip down, making it a poor choice. So, flatter roofs are more compatible with this process.
The structure must also be strong enough to support an extra layer of roofing. If not, that’s a risky choice. A roofing professional can help you evaluate the roof structure’s strength properly.
Roofing Material
Layover work is more common in asphalt shingle roofing. If your home’s roof is made of slate, wood shakes, or tiles, this process is not recommended.
Ventilation Concerns
If the locality is hot and humid, layover work can often lead to moisture buildup between roof layers, leading to mold issues. So, unless the attic is well-ventilated, this is not feasible.
Renovation Plans
If you want to renovate your home (especially the attic or roofline), a layover can be tricky. In this case, a tear-off is a better option. Otherwise, roofers will have to do extra work later, costing you more.
Parting Words
If your existing roof is in top-notch condition, overlay is possible. However, the ultimate decision depends on a range of factors, as mentioned above.
So, it’s high time you considered the pros, cons, and key considerations to reach a conclusion. It’s even better if you can discuss this further with a roofing expert. However, are you uncertain about which roofers to choose? Contact us at LA Roofing Materials, and we’ll get you acquainted with the best roofers in the industry!