The Best Underlayment for Vinyl Siding

GreenGuard Q250_FQ250 Siding Underlayment_US

Even if wood siding is structurally sound, it needs to be scraped, painted and replaced every three to seven years to keep it looking good. Over time, more and more wood panels will need to be replaced as they are continually power-washed and restained.

To avoid future repairs and maintenance, a contractor may recommend that homeowners choose vinyl siding as it’s lower maintenance and can provide long-term cost savings.  

In new construction, builders may just choose vinyl siding from the beginning but with a renovation, the cost of removing the old siding can cut into the cost savings of the project. That’s why many contractors are taking a unique approach: installing new siding overtop of the old.

New Siding Over Old Siding

One of the benefits to installing vinyl siding directly over a home’s previous siding is decreased labor and costs since you don’t have to rip the old siding off first.

Unfortunately, existing siding isn’t completely flat or level, and it needs to be both in order to apply the new siding. That’s why an underlayment is necessary: To smooth out the existing surface and give the vinyl a level finish to adhere to.

GreenGuard siding underlayment creates a smooth, level surface that is ideal for vinyl siding attachment. It also offers other benefits, such as energy efficiency, moisture resistance, easy installation and durability.

Energy Efficiency

GreenGuard Q250_FQ250 Siding Underlayment_US

If the new siding material isn’t pre-insulated then underlayment may be needed to provide an added layer of thermal protection. Because a tight building envelope and exterior insulation are so important to increasing interior comfort and lowering energy bills, the installation of new siding makes it the ideal time to add to the insulation and increase the energy efficiency of the home.

GreenGuard XFP14 siding underlayment also offers a reflective surface on one side, which increases the insulation of the exterior by three times more than other underlayments, and makes it more energy efficient. This, in turn, creates financial savings on energy usage.

Moisture Management

Vinyl siding is one of the few materials that does not need the addition of a rainscreen in wet areas as it drains well on its own.

GreenGuard’s siding underlayments are perforated to allow moisture vapor to escape. They are also tested and certified to be installed as a full weather resistive barrier. These properties enable the siding underlayment to block air and water penetration while allowing the moisture vapor to transfer through the product.

Easy Install

GreenGuard Q250_FQ250 Siding Underlayment_US

Vinyl siding is lightweight, easy to cut and easy to install, which makes it the natural choice for contractors.

GreenGuard’s siding underlayment is designed to be sized and installed quickly and painlessly. Available in fanfold bundles (where the insulation is crimped and folded to ensure it lays flat), the underlayments are made of closed-cell polystyrene, which creates the ultra-smooth, flat and durable surface for adhering the vinyl siding.

The sheets are ¼-inch thick, so they won’t add bulk to your exterior, but will still provide superior moisture management, energy efficiency and durability.

Durable and Long-Lasting

When working with underlayment, you want a product that is going to last a long time. The homeowner won’t want to spend time and money on new siding, only to have to replace it a few years because the underlayment didn’t stand the test of time.

GreenGuard’s underlayments are made of a synthetic material that is not a food source for insects and doesn’t encourage the growth of fungus, such as mold or mildew. This means that the new siding won’t break down or degrade over time.

Make the Best Choice for Your Re-Siding Projects

GreenGuard Q250_FQ250 Siding Underlayment_US

Kingspan’s line of GreenGuard siding underlayments is designed to be lightweight, easy to cut and install, durable, and highly effective at providing superior moisture control and insulation. It can help make the installation a smooth process by providing the level surface needed to install new material over existing siding.

Get the best underlayment material available to ensure that your homeowner is getting a quality siding install from start to finish every time. Learn more about Kingspan’s GreenGuard siding underlayments today.

Kingspan Insulation North America

Head Office & Sales Office – North America

Kingspan Insulation LLC

2100 Riveredge Parkway, Suite 175

Atlanta, Georgia



Call: +1(800) 241 4402