In the interest of saving cost and time, some homeowners may wonder “Can you put new roofing shingles over old ones?” Technically, you could. But would we recommend it? No, we wouldn’t. Here’s why.
Most local building codes only allow a maximum layer of two layers of shingles. In some areas, especially those with a lot of icy weather, they only allow one. That’s because shingles are only one of the multiple layers of your roof; they are really not designed to be layered on top of another. Many roofs are also built to support the weight of one layer of shingles. Adding an extra layer of shingles could be too much for your roof to handle. If you install new roof shingles over old ones, your roof might sag and lose integrity over time.
Layering shingles on top of one another also means you’re not getting a good idea of what’s going on underneath the top layer of your roof. The roof also consists of decking and underlayment. A reliable roofer will always do a roof inspection to see what needs to be fixed before re-roofing. But by not removing your old layer of shingles, you are ultimately opting out of replacing your underlayment. If your underlayment is old and deteriorated, water is more likely to get underneath your shingles and into your roof deck. Unfortunately, that means your roof could start leaking sooner than you might think, and it may even mean you’ll have to replace your “new” roof in just a couple of years.
Part of the roofing job is to remove old shingles and dispose of them. This shows up on the roofing estimate, which is why some clients may think they can save money if they install new roof shingles over old shingles. However, installing new roof shingles over one ones will probably end up costing you more money later on. Any damages that weren’t repaired prior to re-roofing could become bigger problems that end up being more costly. If you end up having to replace your “new” roof sooner than later, that is also a bigger cost than if you had properly disposed of your old roof to begin with.
Lastly, shingle manufacturers will often void their warranty if their materials were improperly used or installed. Again, not only does it NOT save you money, but it will COST you money. It’s crucial to find a local roofing contractor who understands the installation requirements from the manufacturers. This ensures your warranty works for you.
Since 1969, IBEX Roof has been an accredited CertainTeed Select Shingle Master™ contractor. We are proud to deliver only the best results for our customers. Our job is not only to help you repair or replace your roof, but to also make sure it lasts! Many of our customers end up being customers for life, and we do our best to go the extra mile before, during, and after every roofing project. To get a free estimate for your next roofing project, give us a call at 360-218-3108.