Rain Screens: Why They'll Save You Thousands Over the Life of Your Home

A rain screen is a building system, installed before your siding, that leaves a half-inch to three-quarter-inch gap between your framing and your siding. This gap allows the water that will inevitably get behind your siding to dry out without rotting the structural aspects of your building as well as the siding itself.

With a few different systems at our disposal, the range of prices varies, but its by far the most cost-effective way to extend the life of the first line of defense between the harsh climate we live with here in Star Valley, WY - your siding.

Let's talk about how this system works, the different products involved, the costs associated, and most importantly, the benefits of using this system.

How does a rain screen work?

To understand how a rain screen works, we'll first need an overview on how we build a traditional wall assembly. Lets take a look at this picture:

A simple rain screen. Note the Cor-A-Vent SV-3 plastic vent at the bottom and the wooden furring strips used in conjunction. Continuous insulation underneath that.

Without the air gap between your siding and your home, you create the necessary conditions for rot to start forming - we want the water to be able to dry out! By adding something as simple as half-inch strips of ply wood or one-by wood material, we introduce an air gap that allows everything to dry out when it inevitably gets wet.

Even if you aren't putting continuous exterior insulation around the exterior of your home (which is now a code requirement in Star Valley Ranch, WY), the furring strips are installed right over the weather resistant barrier, or WRB. The siding is then installed perpendicular to the furring strips.

However, if you plan on vertically-oriented siding, we have to change to a vent-style rain screen [product, which we'll cover in the next section.

What types of products are available for rain screens?

There's three main types of rain screen products: 1) wooden furring strips (which we showed and talked about above), 2) mesh-roll rain screens, and 3) plastic vent rain-screens (hinted at in the diagram above). Let's dive into the pros and cons of each.

Wooden Furring Strips

This is the OG of rain screens, before we had fancy extruded meshes and plastic venting. Wood is an extremely versatile product, is easy to work with, and is the cheapest (material-wise) of the three main types of rain screens. If you've ever seen a rain screen in the wild, chances are this is the one you've seen.

But everything has its downsides. Wood rain screens are labor intensive to install. We usually use 8' sticks of 1x2. When you get a house that's 30' tall, that labor starts to add up when you consider installing off scaffolding or a boom lift.

Mesh-Roll Rain Screens

This category is the relative newcomer to the market. The well known, and ever expanding, Zip System Rainscreen; Benjamin Obdyke's Rain Slicker Classic; Delta Dry by Dorken.

This category is made up of extruded plastics, sometimes with a weather resistant barrier (WRB) backing. The pros here is all in the install method - these products save a ton of time. They are relatively easy to install without lots of steps involved, the materials cut easily (usually with a knife or scissors), and can be installed with one person.

The downside is the price. I recently priced out the Zip System Rainscreen for a 24'x24' garage, and the total came out to a little under $1700. For reference, the wooden furring strip option is around $450. However, weighing that against the little amount of labor involved, it can make sense as an option.

Plastic Vent Rain Screens

This category has been around for a while in the commercial world, but as ridge venting on roofs. Someone, somewhere realized the vented mesh in the plastic worked well as a rainscreen for siding and the company ran with it - the Cor-A-Vent SV-3 Rainscreen (see the photo above).

Where these plastic vent rain screens shine is when you want to orient your siding vertically. In this type of situation, the plastic-vent and mesh-roll rain screens are your only options. However, you can use this system with any orientation.

The cons with this type except for price (they tend to be just as expensive as the mesh-roll rain screens) and they strike a middle ground between easy to install and tedious (they install a lot like wooden furring strips).

So why do I need a rain screen?

Another look at a furring strip rain screen. Here, the builder straps vertically and horizontally in order to run the siding vertically oriented.

Think about what happens when you trap water behind your siding and between your walls. That siding starts to rot and that rot consinues to move inward (into your home) where its dark and warm. This creates mold in your home which leads to health problems.

You don't NEED a rainscreen, but it is an extremely cost effective way to significantly extend the life of your siding.

It does this by allowing your siding to dry out via the air gap created by the furring strips, mesh, or plastic vent. Allowing your siding to dry out not only protects whatever your siding is made of, it also protects the finish (paint, stain, etc.). It keeps the siding from warping, cupping, cracking and bowing.

This means that instead of replacing your siding every 10-15 years, you replace it every 20 years (with regular upkeep). Not only does this save you money, it keeps your home looking beautiful.

Which system should I use?

Well, a lot of the answer here is, "it depends."

Like I mentioned earlier, if you want vertically oriented siding, the mesh or plastic rainscreens are going to be your only options.

Looking for high performance and cost effectiveness? Wooden furring strips can't be beat.

Want high tech? The mesh rainscreens are a fantastic option that can pencil out to furring strips in the right scenarios.

The key thing to note here is that rain screens are meant to be used in conjunction with a WRB and continuous insulation, but can shine on their own in a remodel situation where it doesn't make sense to take the extra time and money to run continuous insulation and retrofit that with old windows, doors, etc.

I personally prefer the mesh-roll rainscreens. Most of the time I see a lot of labor savings as compared to a more traditional option like furring strips.

So if you're curious about rainscreens, or how we're building better homes, reach out.

We'd love to connect, answer any questions you may have, tour one of our jobsites to see this stuff in action, and simply share the knowledge we have. We find that by sharing knowledge, we get people thinking about these things when it comes time to remodel or build a new home, and that's never a bad thing!