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Frequently Asked Questions
Explore our frequently asked questions page for answers to some of the most commonly asked vinyl siding project questions.
Can you put new siding over old siding?
While it's certainly possible to put new siding over the older siding, it is typically not recommended by serious contractors for several very important reasons. The most important reason is that the older siding is probably sitting on the outside of a wind & moisture barrier that is not doing it's job very effectively. This wall sheathing, Tyvek is the most popular product, provides a moisture barrier that is very important to protecting the interior walls for decades to come. Slapping up new siding on top of failing old siding is like putting a band aid over a potentially dangerous cut, trapping whatever is inside and hoping for the best.
If the older siding is failing, it is very possible that moisture has gotten into the walls and the last thing you want to do is seal this up. Instead, you need to pull the old siding off and do a proper diagnosis of the conditions of the walls. Mold is not only a problem for the strength of the walls and the home, it is also a potential health risk for you and your family.
Once the old siding is removed and the condition of the walls is given a clean bill of health (and corrected if need be), the wall sheathing can be applied and then the new siding can be installed over it. Certainly, removing the old siding will add to the cost, usually $.50 to $1 per square foot for standard jobs. However, in terms of long term cost, removing the old siding can save money in the long run. Good quality contractors will often insist on it so they don't get sued down the road for more failing siding.