Vinyl siding will make your house look more refined, but before you can install it, you need to ensure that there’s a strong, solid wall behind the exterior cladding. This means that insulation and waterproofing are vital parts of the installation process if you want your vinyl siding to last for more years to come.

What do you put behind your vinyl siding? If you own a typical type of residential house structure, the chances are good that you have a combination of wood, foam, and paper.

I’m sure if you paid attention to your house during the construction, at some level, you know what material is behind the siding. But if you forgot, this blog will give you ideas on what you should find under your siding.


What Goes Behind Vinyl Siding?

Here are the possible components you can see under the vinyl siding:

  • Flashing
  • More siding
  • Vapor barriers
  • Water-resistant barriers
  • Materials that protect the substructures

For further information, let’s discuss the materials one by one.

1. House Wraps Under Vinyl Siding

The most common usage of house wrap is to entirely surround the house directly over the sheathing and beneath the vinyl siding with a light paper-like material. Its main function is to keep water and air from leaking through the vinyl exterior.

It is a moisture barrier, but it isn’t completely waterproof. Water can still get through other components if it is exposed to moisture for a long time. It is not necessary to be entirely impermeable because it is located beneath a home’s outside paneling.

Even if it is not stated under your local construction rules, there’s no reason why you shouldn’t have house wrap behind vinyl siding, and many experts feel that it should be considered a legal requirement to make residential houses last longer. 

Moisture and air can penetrate through the small cracks and seams, wreaking havoc behind the siding and causing substantial damage that you may not detect until it’s too late. Despite the benefits of vinyl, having a house wrap as an extra layer of protection is a good idea.

The greatest protection against water and air leakage will be your vinyl siding and the supplementary barrier will be your house wrap. House wraps control the air circulation between components while protecting the walls sheathing and improving the insulation of your home.

It’s a wise decision to install house wrap while siding your home because of its ability to enhance the total integrity of your exterior panel and how easy it is to insert beneath the vinyl siding. You can place foam insulation between the house wrap and vinyl siding to enhance the R-value during the siding process.

House wraps will definitely improve the security of your house wrap. You should include it if you’re already siding your property because applying it afterward will necessitate a complete re-shingling.

House Wrap Installation Under Vinyl Siding

Installing house wrap is relatively easy and will not require too much time during the process. Note that house wrap must be properly installed, or you won’t get the optimum performance from this material. Careless or improper installation of house wrap might not cause extensive harm to your siding, but it will end up as a waste of money and resources.

If you’re wrapping your house completely and it’ll be out in the sunlight for a long time, you’ll want to invest in a material like Barricade Plus that will keep UV rays away from the components. Because it isn’t supposed to be exposed to direct sunlight, typical house wrap should be put and coated in vinyl as quickly as possible. The wrap can grow brittle over time, increasing the risk of tears and lowering its ability to protect itself.

See Also: Windows House Wrap Around Installation Guide

2. Foam Board Insulation

Polystyrene is the most common example of foam board insulation for exterior house panels. To limit airflow, tape the seams where the foam board is kept in place with washer head fasteners. Depending on the composition of the foam board, the R-value of this product can reach up to R-3.5.

To enhance the appearance and value of their property, many individuals install vinyl siding or concrete board siding. Contractors and homeowners are ripping off the original siding and replacing it with a thinner foam board underneath to save more electrical energy.

3. Flashing Under Vinyl Siding

On the exterior part of the siding, flashing may be required in some cases and step flashing should always be put under the siding. Installing step flashing beneath stucco, lap cladding, vinyl siding, shingle siding, and other types of siding is always a smart option.

Yes, installing flashing on the rooftop will serve as a downspout and directs all water down to the eave of the roof underneath the siding.

Note: Flashing always goes behind the house wrap.

If water infiltrates your house, flashing is your last line of protection. Flashing is designed to deflect water away from crucial entry points if it penetrates behind the house wrap.

4. Weather-Resistive Barrier or WRB 

Before applying new siding, the existing siding needs to be flat and leveled. Underlayment is used to smooth out the current surface and provide the vinyl with a nice base to attach to.

Between the siding and sheathing, WRB is inserted. This could be a type of asphalt paper such as the HardieWrap®. Weather-resistive barriers are an excellent way to keep water out of the house while also allowing moisture to escape.

5. Vapor Barriers

Vapor retarders keep water out of the siding and down the wall by preventing it from seeping through the components. Companies like Tyvek® make a newer form of drain wrap that helps us keep the water out and away from the siding.

Today’s Homeowner Tips

Keeping the water out of the house isn’t the main concern. It’s all about allowing water to run down the siding.

This concludes our blog about the possible components you can find under vinyl siding. Remember, your chosen protective equipment under the vinyl siding is a make-or-break proposition. The best choice depends on your location and preference.

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Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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