Best Rainscreen Systems for Wood Siding Projects

Written by Chris Nolan on Tue, Mar 9, 2021 @ 05:03 AM

Wood siding is naturally beautiful. How can you protect your wood siding better and help your home perform at a higher level? The health value benefits of a rainscreen assembly are more widely recognized than ever before. And not just by architects and builders. Homeowners and property owners are learning of the many benefits of a well-designed rainscreen system. What are the best wood rainscreen systems and methods?

Vertical wood rainscreen with Climate-Shield CS2 rainscreen components

What is a Wood Rainscreen?

First off, let’s take a quick look at what a wood rainscreen is.

A rainscreen is a method of spacing the siding away from the building’s weatherproofed exterior. A ‘wood rainscreen’ is simply a rainscreen system that uses wood siding.
The siding becomes your home’s first line of defense from the weather. It creates a ‘shield’ to keep rain, snow, sleet, and other weather away from your structure.
Because the siding is placed away from the home or structure, it leaves a space, called a ‘rain screen gap’ or wall ‘cavity’. This space is crucial for a healthy design.
A well designed rainscreen gap allows bulk water to drain out, before it effects your home or building.
The gap can also allow any moisture trapped inside the structure to egress.
The gap also provides a passive insulation layer, further protecting your home.

Why Use a Wood Rainscreen?

Well-designed rainscreens protect your home or building from the weather outside. They also allow your home to ‘breathe better’, ventilate better, reduce the potential for mold, and provide a passive insulation barrier to boot. There are many types of wood rainscreens, that is, a rainscreen system that uses wood siding.

The trouble is, all wood rainscreens look pretty much the same from the outside. But it is the area behind the siding, the part that you can't see after it's installed, that provides all benefits. How can you tell the difference? How can you tell which wood rainscreen system is right for you? Let’s take a look at the various wood rainscreen options.

Basic Wood Rainscreen using wood furring strips

Using a furring strip is the most basic way to create a wood rainscreen. Most skilled carpenters and siding professionals have experience using a wood furring strip to space the siding off the exterior wall of a façade. This space the furring strips create behind the siding is known as the ‘rainscreen gap’ or ‘wall cavity’.

Building scientists agree that a rainscreen gap of ¾” behind the siding is highly effective. That’s why a ¾” thick wood furring strip makes so much sense.

Pros of a Wood Rainscreen with furring strips:

Furring strips are readily available.
Hardwood furring strips work best.
Most experienced contractors are familiar with proper furring strip installation techniques.
¾” thick furring strips automatically create a ¾” rainscreen gap.
This type of rainscreen installation is 80% effective by design, making this method far more effective than not using a rainscreen.
Using a weather resistant tape over the furring strips makes them more durable and less likely to rot.

Cons of a Wood furring strip rainscreen:

The labor time of installing furring strips takes longer than using a rainscreen clip.
The material cost and labor cost of furring strips, typically adds about $2 or so per square foot to the project cost.
Furring strip rainscreens are about 80% effective by design, but rainscreen clip installations without furring strips are roughly 96% efficient.
If not installed properly and protected, wood furring strips can rot.
Must ensure air flow at top and bottom of each cavity- this is a closed joint rainscreen.

See Typical T&G Wood Siding Profiles for Closed Joint Rainscreens

The Climate-Shield Rainscreen System

A wood rainscreen assembly using furring strips is better than no rainscreen at all. However, there are much better ways to create a higher performance wood rainscreen. The Climate-Shield Rainscreen System was developed to meet these needs. The main difference between the Climate-Shield Rain System and furring strip rainscreen assemblies are:

No furring strips are needed. This saves installation time and reduces your labor and material costs.
Open Joint rainscreen. The wood siding is designed to leave a small space between the siding boards. This creates an ‘open joint’ rainscreen. An open joint rainscreen provides superior ventilation and a healthier wall assembly.
Pressure equalized. A ‘pressure equalized’ rainscreen is also created. This means that your wall cavity will dry out, quickly, effectively, and effortlessly. A pressure equalized rainscreen also provides superior performance in high wind zones.

Climate-Shield_Rain_Screen_System_at_garage_area

Climate-Shield wood rainscreen siding project

Climate-Shield CS2 Rainscreen System and Components

The Climate-Shield CS2 rainscreen system is the most robust and highest performing group of components. The basic system uses the CS2 rainscreen clip and a starter rail, to create various types of rainscreens. With the CS2 assembly, you can design and build a vertical, horizontal, or diagonal wood rainscreen.

The CS2 rainscreen system can be used for commercial or residential designs over a variety of different wall assemblies, including plywood, masonry, rigid insulation, exterior drywall and more. Additional Climate-Shield components are available with the CS2 rainscreen system including a horizontal starter rail, vertical starter rail, attachment channel, z-girts, and wood and aluminum outside corner options.

Here's how the Climate-Shield Rainscreen system works:

CS2 rainscreen wall assembly

Pros of a Wood Rainscreen with CS2 Rainscreen Clips:

The CS2 rainscreen clip automatically creates a consistent ¾” rainscreen gap, without using furring strips.
Because there are no furring strips, a ‘pressure equalized’ rainscreen is created.
CS2 uses two screws per rainscreen clip for higher holding power.
The Climate-Shield rainscreen system with CS2 components is engineered to exceed the wind load requirements in hurricane and high wind zones.
Rated for over 220 MPH winds and seismic equivalent.
Installs vertically, horizontally, or diagonally.
Can be used on commercial and residential designs.
Installs quickly.
Minimizes wood siding waste.
Additional Climate-Shield accessories are available for various designs, including z-girts, attachment channels and outside corner options.

Cons of a Wood Rainscreen with CS2 Rainscreen Clips:

Because of the ¾” rainscreen gap behind the siding, window and door trim may be required around fenestration.
Although the system installs stronger and faster than furring strip installations, 2 screws per clip takes slightly longer than 1 screw per clip.

Climate-Shield CS10 Rainscreen Clips and Components

The Climate-Shield CS10 rainscreen system is designed with a lower clearance 10 mm rainscreen gap (3/8”). It is designed for faster installation of horizontal siding and soffit installations.

Ipe wood rainscreen siding using the Climate-Shield CS10 specialty clip

Pros of a Wood Rainscreen with CS10 Rainscreen Clips:

Creates an open joint, pressure equalized rainscreen.
Installs easily with 1 screw per rainscreen clip.
Works great for residential horizontal siding installations
The lower clearance works great around most window and doors, without the need for additional trim around these openings.
Excellent option for residential remodeling and re-cladding projects.
Ideal for soffits
Designed to meet wind load requirements more than 160 MPH.

Cons of a Wood Rainscreen with CS10 Rainscreen Clips:

Although the CS10 is not quite as robust as the CS2 rainscreen components, it still outperforms wood furring strip installations.
The 3/8” rainscreen gap dries out quickly, but not quite as fast as the CS2 rainscreen clip.

Still trying to decide which wood rainscreen system will work best for you? Here’s a Comparison chart to outline the differences between the wood furring strip option and the two Climate-Shield rainscreen options listed above.

Compare Wood Rainscreen Installation Options