There is something about a clean and simple wood “screen” that is suspended off the face of the wall that is at the same time both modern and refreshing. There are all sorts of tricks and benefits that come with this sort of detailing and based on how often I see this sort of expression – what is essentially a rain screen – it would appear that a lot of other architects are also enamored with wooden rainscreens.
It all starts with an idea of how to articulate a concept. This is one of the very first sketches that was produced that considered a wooden rainscreen – you can see just how far this idea evolves over time in the next image (which is the exact same portion of the house) …
I should quickly explain what a “rainscreen” is so that we can all move past the industry jargon. A rainscreen is a more of a system than a thing – and there are a few basic items that need to exist in order to create a rainscreen. Rainscreen’s are an exterior wall detail that stands away from the main wall assembly, you HAVE to have an air gap at the top and bottom of your screen, you have to have a capillary break between the main wall assembly and your rainscreen, and rainscreens are not load-bearing.
The weather here in Dallas was exceptionally nice this last weekend and I took the opportunity to drive around town checking in on a handful of projects we have under construction that don’t normally receive (for one reason or another) much screen time here on the site. One of the projects I checked in on is on the downhill side of construction and there is a wooden rainscreen that is finally getting installed. This is a simple little detail but it took several hours of working through details to get everything figured out.
Because I like to show drawings, and all signs point that you like to look at drawings, I’ve included a few here that I hope will help tell the story of this rainscreen. This is the full elevation of the wall that you see above in the first photograph. In this drawing, you can see that the wall cladding is painted brick, there are a handful of windows, and the wooden rainscreen wraps around the building mass essentially at the second level. One of the things I love about these sorts of details is that it allows us another material, as well as a new pattern, to work with as we articulate the geometry and overall building form without having to modify the actual footprint of the building.
This is essentially the same drawing, but this time I have overlaid the rainscreen panel dimensioned drawing to help clarify what you are looking at in the very first photograph. As we were working through the details, we had conversations to address questions like:
- How can we streamline the assembly?
- How can you access the brick wall for maintenance years from now?
- Can the panels be built in a controlled environment to maintain consistency?
- How can we reduce and simplify the number of unique components?
As we worked through these sorts of questions, it fundamentally shaped the end product. Of course, as soon as we thought we had it all figured out, the structural engineers said they wanted everything to be 5x bigger … which was unacceptable. Then comes the back and forth push and pull process that happens when you try to do something that doesn’t come off the shelf or out of a magazine. In the end, we got things to be about 90% of where we originally designed them just by reducing the size of the panels and really drilling down on the spacing of the brackets.
Speaking of brackets … here it is. Before anybody loses their mind, this picture (and the next one) are out of sequence and are from a site I made months ago before there was any brick on the house. This was one of the early mock-ups that were made to verify the simplicity of the process.
Not to discount the attention required from the contractor, but it turns out that this is a pretty simple process. The most complicated part was the math needed to make sure that the brackets were all installed in the proper locations prior to the brick being laid.
This is a larger look at the mockup process – pretty exciting to see the rainscreen in place … and it was a complete downer to see it removed but we still needed the brick to be in place.
The wood is Western Red Cedar in case you were wondering – and we are going to leave it unfinished so it will eventually silver as it ages.
This plan view through the wall makes the assembly a bit more obvious – at least I hope it does. You can also see that there is a slight taper to each section of cedar that is in the panel. The pattern isn’t completely random but everybody would be the loser if I were to try and explain it here.
Finally, a very long drawing to help illustrate the location of the steel brackets that tie back through the brick to the structural framing. If you look really close, you will see that there is a secondary steel bracket that helps secure the cedar into the “panel” as well as limit the amount of possible bending and twisting that would occur in these boards over time. These brackets allow the panels to be assembled on the ground than then lifted into place. Somewhere on my desk is the math I did to calculate the weight of every individual panel on the project – it’s impressive. Turns out it was worth the hour I spent so that we could share this exact information while we were meeting with the structural engineers and eventually the contractor. They might be heavy if you were to try and pick one up by yourself, but structurally they are relatively light.
A final look at the rainscreen from my weekend field trip. I should point out to all of your eagle-eyes that the notches that you see on each piece of cedar follow the horizontal datum for all the window penetrations as you follow this screen around the building. In this particular image, you can see how the notches line up with the window at the top.
To give you an idea of the timeline, I posted a picture of this rainscreen just over two year’s ago. If you are interested, we have a whole bunch of photos that were taken of this model that could be fun to explore. You can see them all on my company’s website (here).
Everybody likes to look at models.
The last thing I will share with you before you head back to whatever it is you are probably supposed to be doing is that the model of this house is a celebrity. At least, the sort of celebrity that ends up on TV, which is exactly what happened. We were contacted by a production company that wanted to use this model in an episode of ‘Queen of the South’, a show currently airing on USA Networks. We had an office party at my house to eat, drink, and watch our model become more famous than any of us … we had a good time.
Hope you enjoyed this peek behind the rainscreen – I am excited to show you the final product once it all comes together.
Source: Life of an Architect