If you are trying to keep a building safe from weather damage, consider Rainscreen Cladding an ace up your sleeve. A rain screen system brings out the best in modern cladding materials, such as ACM and HPL, by installing paneling in a way that limits water damage by directing it off and away from the base wall.
Previously, we have spoken about how important it is to waterproof during cladding installation. Now, we bring it all together by explaining what Rainscreen Cladding is, how it is installed, and how this design increases the efficacy of facade materials.
How Rainscreen Cladding Works
Keep the Water Moving
Provided that the base wall is wrapped with an Air Vapor Barrier, the problem of waterproofing is not keeping water out from behind cladding panels, but rather creating the right environment for water to flow through that space expediently.
That is why, when using a rain screen system, cladding panels are installed on base plates so that they do not rest directly on the base wall, thus creating an air cavity that allows steady circulation. For Rainscreen cladding that is up to code, typically this gap is about one to two centimeters wide.
In a ventilated design, which leaves open the top and bottom of the cladding, air can circulate freely along the back of the paneling. Rain, including potential runoff from the roof of the building, flows into the joinery, or top, of the Rainscreen, for it to be snatched up at the bottom by flashing that directs it away from the building.
The principle is that water damage is mitigated greatly when water is not allowed to linger, and this method is tailored keeping a consistent and quick flow even during the worst storms.
Facilitate Air Circulation
Despite its name, Rainscreen Cladding benefits a property even when the skies are clear. Think back to science class, and you will recall that hot air rises, which is why the ventilated design of Rainscreen Cladding can help in the summer when air conditioning machines everywhere are working overtime.
Hot air will not loiter along your building’s envelope, instead, it will chimney up and out the top of the Rainscreen, allowing the cooler air from below to replace it. This lessens the impact that the heat of the unconditioned environment can have on the temperature inside a building, and another reason why Rainscreen Cladding is an innovative facade solution.
The constant movement of air through the space between the cavity and the base wall works to dry out mold and mildew causing condensation, and ensures that the Air Vapor Barrier and the Cladding material can work to its full potential. With proper installation, the Rainscreen will create a pressurized environment that forces this steady circulation.
Methods for Rainscreen cladding will vary slightly from one installer to the next. In all cases, the process begins with a structurally sound base wall that is ready to handle the steady wind that will shoot through the air cavity. An Air Vapor Barrier (AVB) wrapped around the base wall will go a long way in this regard and will act as a final defense against water that gets into the gap between the wall and cladding panels.
Flashing at the bottom of the building’s envelope should be lair prior to cladding, to form a basin will lead water from the Rainscreen’s air cavity away from the building. Once the AVB is snugly fastened and flashing is in place, installers can use its surface to chart out a grid to ensure that the proceeding work translates clearly from the original blueprint.
Just like you would begin a puzzle by placing all the edge pieces, installers first fasten the vertical perimeter extrusions, and then the horizontal perimeter extrusions, along the edges of the wall. Next, come the horizontal back plates, cut to approximately 3 inches and installed on the bottom of the wall, segmented along the sketched-out grid to ensure proper placement. A top cap is then snap locked onto these backplates, completing the frame that surrounds the base wall. This will serve as the basis for the Rainscreen.
Filling out the Grid
After the frame is established, installers move on to filling out the rest of the grid. Vertical back plates are fastened to match the lines sketched out from top to bottom. Long links make up most of this space, whereas installers use half plates to accommodate the intricate areas around windows, doors, and unique design flairs. Horizontal lines on the grid are dotted with segmented back plates, cut to the same specifications as those used for the bottom of the frame.
With the extrusions and back plates installed on the base wall, you will be able to see the space between the wall and the end of the brackets, which will soon be the air cavity for the rain screen system. To prepare for the installation of cladding panels, clips are fastened to each backplate. The thicker side of the clip goes against the wall, offering support for the extrusion that will be the air cavity.
Bringing it all Together
Cladding panels are then attached to the clips. It is important to begin in one of the base wall’s corners, and then work out from that initial piece. A common dry seal method for securing panels is to install vertical, and then horizontal, top caps that will create a pressurized environment within the air cavity.
At the top of the Rainscreen, installers often fasten a metal profile, otherwise called joinery, that limits the amount of water let in, while still affording proper air flow to the cavity. The bottom of the Rainscreen is made up by the already installed flashing specifically designed to direct water that is caught in the cavity away from the building.
Get the Most out of Modern Materials
Many modern cladding materials accommodate Rainscreen systems. Paneling made from products such as ACM or HPL are particularly suited to the process, thanks to their resistance against environmental and water damage. The success of Rainscreen Cladding teaches us that proper weatherproofing hinges on parity between innovative installation and quality materials. For example, ACM can hold its own in a fight against rain, but its use in a Rainscreen brings out its maximum potential.
This is one of the many reasons why, at Wiedehopf, we are committed to the entire cladding process. Over years of experience within the industry, we have learned that the most successful cladding projects pair durable materials with sound installation methods. Rainscreen cladding methods are engineered to bring out the best in the modern materials that we supply.
If you seek a holistic approach to your next cladding project, and if you seek a Rainscreen cladding system for your building’s facade, you will find a reliable partner in us! Get in touch to hear how we can assist and facilitate your cladding journey.