Vinyl Siding: Effective Insulator or Not? (Everything You Need to Know)

There are many advantages to vinyl siding. It’s cost-effective and very easy to install and maintain. However, one question remains: is it an effective insulator?

If you’re investing in vinyl siding and you want to understand how to maximize its insulating properties, read on. You’ll discover all you need to know about vinyl siding and insulation.

Does Vinyl Siding Help Insulate A House?

Vinyl siding has two layers: one is capstock, and the other is substrate. Because of these two layers, it’s able to stop heat from leaving or entering the building.

This is what keeps your house cool in summer and warm in winter.

If you need something to insulate your home from the elements, vinyl siding is a smart choice. It’s very resistant to different weather conditions. You can count on it to hold up against hard rain, snow, and hail.

What about if you live in extreme cold?

Vinyl siding might not be your best choice. It has the potential to grow brittle and crack under freezing conditions. If you do choose to use this material, make sure you invest in the best quality variations possible.

If insulation is important to you, it makes sense to invest in insulated vinyl siding. It helps to improve your home’s energy efficiency, cutting your costs all year round!

Overall, although all vinyl siding has some insulating properties, it’s far more effective when combined with additional foam insulation.

With the added protection of foam insulation, you can count on your home to be comfortable throughout every season.

In winter, you’ll be kept cozy. In summer, your vinyl siding will keep your house cool.

Vinyl Siding: Insulated Or Not?

When deciding between normal vinyl siding and the insulated kind, you may wish to keep the following considerations in mind.

  • Cost:
    Insulated vinyl is more expensive than the non-insulated kind. However, over time you can recoup these costs through utility bill savings! Because insulated vinyl is bulkier, it may cost more to ship too. The overall price will depend on the style you choose as well as the type.
  • Appearance:
    Both insulated and non-insulated vinyl comes in a range of styles. Insulated vinyl siding uses contoured foam which supports the siding panel, though, and this added support makes it manageable for manufacturers to make vinyl siding in darker, richer colors. 

    This foam also helps maintain sharp, crisp lines so the appearance of wood is more easily emulated.
  • Installation:
    The installation process is similar, but you’ll find that insulated vinyl siding is a little more difficult to install due to its additional thickness.

    It must be cut with a saw, for example. An experienced installer should be able to install either kind with ease.

  • Durability:
    Insulated vinyl has higher levels of impact resilience than traditional vinyl siding. The foam used also features built-in termite protection.

    Both kinds are low maintenance and long-lasting, but only insulated vinyl siding offers this extra layer of protection.

Do I Need Insulation Under Vinyl Siding?

If you have a lower budget for your project, you plan to install the siding yourself, or you aren’t concerned about the long-term implications of your choice, then vinyl siding without insulation will do the job.

However, if you want to benefit from increased energy efficiency and all the savings that bring, then insulated vinyl is a must!

It can make your home feel much more comfortable no matter the weather outside.

Of course, insulated vinyl is an investment: it’s often much more expensive than the non-insulated kind. It costs more for a reason, though.

It’s more protective and durable, for instance. It will keep your home warm in cold weather and cool in the heat.

If you live in a cold climate, you need insulation under your vinyl siding more than most.

Although you’ll have to pay a substantial sum, your utility bills will decrease, meaning you’ll earn that money back over time.

Foam board insulation under your vinyl siding offers improved moisture control, which can help to avoid mold development, as well as improved thermal performance. 

Whether you feel you need this or not really depends on whether you feel you can live without these advantages.

If you feel you can, then it makes sense to choose the more affordable option: uninsulated vinyl siding.

What Kind Of Insulation Should I Use Under Vinyl Siding?

These days, foam board insulation under the vinyl siding is very popular. You’ll see it both in new builds and on renovation projects.

One reason this is a popular option is that it offers improved moisture control. It moves the dew point to the outside of the wall assembly, avoiding condensation within the cavity.

Siding is kept away from the exterior sheathing. This means that any vinyl siding leaks are separated from the home itself by a layer of protection. It won’t damage water infiltration.

This kind of insulation also improves thermal performance. It adds to the R-value of a home, improving your energy efficiency and saving you money on utility bills.

Of course, even if you choose this type of insulation, the thickness of the foam matters. Thicker, high-quality materials are preferred, although they are more expensive.

Beyond these benefits, air infiltration is also improved. This makes the insulation perform better, especially if fiberglass batt insulation is used.

Exterior rigid foam board insulation even makes your home quieter!

All of these advantages explain why it’s considered a good investment and why this is such a common method of insulating a house these days.

Is House Wrap The Same As Insulation?

House wrap is not the same as insulation.

They can be installed together, and they complement one another very well.

House wrap should generally go under rigid foam; however, your contractor will be able to assess your particular situation and make the best decision for your home.

Whether the wrap or the insulation is installed first, both together will prevent air leaks and infiltration.

Before, house wrap was generally asphalt-coated felt paper. This has changed over time.

Now, house wrap is usually a light, synthetic material. Usually, it is placed between the siding and the sheathing of a home.

In contrast, insulation is often a foam material.

Although both house wrap and insulation share a similar purpose, they aren’t the same product and it’s commonplace to use both together.

Do I Need House Wrap Behind Vinyl Siding?

Vinyl siding is almost waterproof, so is house wrap really needed? Yes.

It’s still possible for moisture and air leaks to enter your home, even if you have vinyl siding.

The material is waterproof, of course, but small cracks can still be created during the installation process.

This is where problems begin! The worst part is that the siding can hide these problems for you, allowing them to worsen without your knowledge.

Although vinyl siding is very durable and dependable, it makes sense to enjoy an extra level of protection by using house wrap.

It will reinforce what your siding is already doing: defending against moisture and air! Consider it a second line of defense.

Because house wrap is very easily installed, there’s no reason not to do so.

If you include foam insulation too, you’ll also increase your R-value! Your house will perform at higher levels of energy efficiency.

Best House Wrap For Vinyl Siding:

The purpose of house wrap is to provide a drainage plane. This protects sensitive materials from direct exposure to precipitation. It helps walls dry out so they aren’t damaged by excessive moisture.

Now that you’ve decided to install house wrap under your vinyl siding, you’re probably wondering what is the best kind available.

There are three basic types of house wrap: asphalt felt, Grade D building paper, and synthetic house wrap.

Under vinyl siding, you might consider Barricade House Wrap a strong option. This is an economical product.

It is resistant to tearing, and it offers a high level of protection against moisture. It’s also semi-transparent in design, making it easier to see and install.

When choosing a house wrap, make comparisons based on:

  • durability
  • water resistance
  • air resistance
  • vapor permeability
  • drainage capacity

Beyond Barricade, you might consider brands such as Tyvek, HomeGuard, CertainTeed, and the ZIP System. These are some of the most well-known names on the market.

Remember, you should always install strapping that separates the siding from the house wrap.

Why? Because otherwise, the wall will take longer to dry.

by Richard Kelly

Having experienced significant success as a house flipper, I am often approached with questions about all things home improvement. That’s why I decided to start this site. My objective is to share all of the insights I have accumulated over the years so other people can design the homes of their dreams.