Breathing Wall Mass Timber Research

Water Bath Workshop

The student becomes the teacher. Last week, as part of the workshop series for the new 5th-year class, the current Breathing Wall Mass Timber Research Project team ran a workshop on water bath modeling. Water bath modeling is a way to visualize the flow of heat in a building using fluids of different densities to represent warmer and cooler air. In this case, the team used regular water and salt water with ink. The salt makes the water denser and therefore it sinks, which allows them to simulate warm air. Now, of course, warm air actually rises, so the entire model is tested upside down. The ink makes the heavier salt water visible as it flows through the model, allowing them to see how the heat flows through the space.

Water bath visualization of heat flow through Red Barn

This workshop was built upon the workshop the team did last year with Salmaan Craig, Kiel Moe, and David Kennedy. This year it served as a primer to the workshop that Sal, Kiel, and David ran on the concept of thermal mass and the science behind it, which forms the basis of one of the projects a new 5th-year team will be undertaking. The water bath modeling served not only as an introduction to a new way of thinking about buildings, but also provides the students with a new analytical tool to use in their future work.

Stay tuned for the return of the white lab coats.

For science,

The Buoyant Breathers

Soundtrack: Muddy Waters | LP

Scaling Up

For the past few months, we have been testing the Breathing Wall on a small scale to get an understanding of how it operates without any external variables. Big things are happening down here as we are moving up in scale! As we do, we gradually add different variables and tune the Breathing Wall to adapt. Our current Breathing Wall tests are being run with a 12”x16” solid pine panel. Using our trusty test box Zelda, we will now be experimenting with a 3’x3.5’ laminated mass timber panel!

These larger scale tests will allow us to experiment with different hole spacings on a laminated panel. Will a Breathing Wall work if a hole hits a lamination? Can we size it to never hit a lamination? How big can we make the holes before they are too big? Too small? How much unintentional air is coming through the laminations and not the holes? All questions that will shortly be answered after a few weeks of testing. This is a big step in working on the overall pod design and designing the Breathing Wall technology to scale up in size.

Pod design and details are in the works. Stay tuned for some construction and science collaboration.

Gaining mass,

The Massive Breathers.

Soundtrack: Larger than Life | the Backstreet Boys

Full Scale Wall Mockup

This August we traded our lab coats for hammers and built us a wall! With all the excitement of the threaded rod panel performing so well in our small scale infiltration tests, we wanted to make sure the four of us could build a full-scale stable, tight, flush mass timber wall. Still unsure about which lamination style to use, we decided we ought to build both a vertically laminated wall as well as a horizontally laminated wall.

The rough cut lumber proved to be the first hurdle in this wall mock up. We had to sort, cut, plane, and rip down each 2” x 6” x 12’ piece (72 total!) for the wall – not particularly difficult, but definitely dusty. Using a template, the next step was to drill 5 holes in each lamination for the rod to thread through (360 total this time!). Our second hurdle was setting up cribbing on Morisette’s campus which an afternoon and some 2x4s (nominal for once) handily took care of.

On a sweltering afternoon (excellent planning), we started the construction of our vertically laminated wall. Just two hours later, each piece had been threaded on and the wall tightened down. Though extremely aesthetically pleasing standing on its own, the wall was hard to tighten down, and light was shining through a few of the laminations- not ideal for a pod we are trying to make air tight.

The rest of the day was spent disassembling the wall and prepping to build the horizontally laminated wall. We prepped enough wood to make each wall 12’ x 12’, so we essentially flipped the vertically-laminated wall on its side. With the threaded rods standing vertically, we quickly stacked all 72 pieces in a little under two hours. While a little bit faster than the vertically-laminated mockup, the most noticeable difference between the wall mock-ups was tightness. Gravity was on our side with the horizontally laminated wall with the weight of the pieces pressing each-other together from the beginning, so we were able to tighten down the rods to the point that no light was coming through. Success!  It was also much easier to flush the interior surface of the wall to the cribbing with the help of our handy-dandy 10 lb sledge. So as much as we love the aesthetic of the vertically-laminated wall, since our project is about rigor and infiltration (for science!), you can catch those horizontally laminated walls in our pods.

Stay tuned for updates on those pods, our ongoing experiments, and how we’re considering repurposing our Test Fan to help cool down our studio.

Sweltering,

The Melting Breathers

Soundtrack: We Didn’t Start the Fire | Billy Joel