Skip to main content

«  View All Posts


Replacing Siding: Can New Siding Be Placed Over Old Siding?

November 29th, 2012 | 6 min. read

Replacing Siding: Can New Siding Be Placed Over Old Siding?

Print/Save as PDF

HardiePlank siding installation

Before starting your siding replacement project, you want to know what goes into the cost, installation, warranty, and more. 

There are so many questions you need to be answered to feel confident in the siding type and contractor you use. One of these questions you have is…

Can my new siding be installed on top of my current siding? 

Southwest Exteriors offers high-quality siding replacements with James Hardie fiber cement siding. Because we’ve been a San Antonio contractor since 1989, we’ve helped thousands of homeowners transform their homes. 

About 40-50% of siding projects we install are overlay projects, meaning the homeowner’s current siding was used as the substrate for their new siding. 

To know whether your current siding can be used as the substrate for your new siding, there are three key questions to consider. 


3 Questions To Consider To Know If Your New Siding Can Be Installed On Your Current Siding 

There are many benefits to using your current siding as the substrate for new siding. It decreases the overall cost of your project, makes installation quicker, and doesn’t affect the quality or longevity of your new siding. 

But, not all siding can be used as substrate. 

Consider these three questions to determine whether you can install your new siding on top of your current siding. 


#1. What is the condition of your current siding? 

The first determining factor to consider is the condition of your current siding. To use your current siding as the substrate for new siding, it must be in pristine condition. 

If your current siding has any damaged areas, such as rotting, cracking, or peeling, it must be removed before a new substrate or siding can be installed. The siding must be 100% intact and in good condition to act as a substrate for new siding. 

For example, you may have a patch of siding that has chipped off, causing minimal rot damage to the interior wall behind that siding. If you install new siding on top without repairing the siding or rot, it will only worsen and spread throughout your entire home. 

The more damage will cause you to have to replace your siding again soon, and it will cost much more than before. 

The Bottom Line: Your current siding must be in near-perfect condition for new siding to be installed on top. If not, you risk further damage to your substrate and home. 


Download this FREE guide to James Hardie siding!


#2. Do you have the right type of siding to be used as substrate? 

The next thing to consider after determining if your siding is in the right condition is if you also have the right type of siding. 

Certain siding types, like traditional stacked lap siding, stucco, brick, and stone, cannot be used as substrate. This is because their material cannot hold siding on top of it and does not provide an even surface for installing new siding. 

Most sheet sidings, even with inward banding, can be used as a substrate if in good condition. This is because the banding goes inward and can be properly filled to create a flush surface for the new siding. Some masonite siding can also be used as substrate as long as it is in near-perfect condition. 

Outward banding and stacked lap siding creates an uneven surface, so it must be removed. 

The Bottom Line: Your current siding must create an even and flush surface for the new siding to be installed atop it. 


#3. Do you want or need added insulation to your home? 

The final question to ask when considering installing new siding on top of your current siding is whether you need insulation replaced or added to your home. 

In many older homes, the insulation within the walls becomes old and deteriorates. Some homes may not even have insulation in their walls. This means it is not doing its job of insulating your home as well as it should. 

If you know you need to replace, repair, or add insulation underneath your new siding, then your current siding must come down for the insulation to be added. 

While it is true that new siding can improve the overall insulation of your home, you need a strong foundation. If you want your new siding to perform as well as it should and protect your home for the future, you must ensure you have the proper insulation underneath your siding. 

The Bottom Line: If you need new insulation installed within your home’s walls, you must have your current siding removed and the new substrate installed. 


Schedule your commitment-free consultation today!


Now You Know: Can You Place New Siding Over Existing Siding? 

Now you know three crucial questions to determine whether your new siding can be installed over your current siding. 

Using your current siding as a substrate for your new siding has numerous benefits, like a lower project cost and quicker installation time. 

If you want to know if you can place new siding on your existing siding, remember these three things: 

  1. Your current siding must be in excellent condition
  2. You must have the correct type of siding to provide an even, flush surface
  3. You cannot install, repair, or replace new insulation with an overlay project 

With these three points in mind, you can determine whether your siding can be used as a substrate for your new siding. 

Whether you install new siding on top of your current siding or need your siding torn off and new substrate installed, you must find the right contractor for a successful project. This means knowing what to look for and what mistakes to avoid. 

Check out this article that outlines five common mistakes to avoid when hiring a home remodeling contractor. Then, you can find the right company to replace your siding, take care of your home, and avoid wasting your time, energy, and money. 


Ready To Replace Your Siding With A Trustworthy Contractor? 

Southwest Exteriors offers high-quality siding replacements, including full siding tear-offs and overlay projects. 

We promise to educate you on the entire siding replacement process and provide you with expert recommendations, whether it includes us in your project or not. 

Start your project today and transform your home with Southwest Exteriors. Schedule your commitment-free consultation with a design consultant and get the look you love coming home to!



A button with a background of lap siding that is beige with the words, "want to learn more about James Hardie siding? As the leading manufacturer of fiber cement products, James Hardie siding is one of the most durable, long-lasting products out there.   Learn more about James Hardie siding, like their products, styles, and more in this guide." With a blue button that says "Get my guide" and three sample pages previewing the guide.