Breathing Wall Mass Timber Research Project

Steel Fabrication

The steel for the spreader angles and plates has been delivered and the team has been working on fabricating those pieces. The plates and angles will run along the walls, floors, and ceilings edges in order to evenly spread the load throughout the wall/floor/ceiling when the threaded rods are tightened down. Each plate and angle has to be cleaned, holes torched, and then coated with a sealant to prevent weathering. Once the steel is finished, the team can begin processing the wood for the walls and ceilings using those plates and angles as templates. 

As the pod begins to become a reality, the issue of properly staging the construction process to be as efficient as possible is becoming an important topic. To that end, the team decided to fabricate the trusses before beginning to build the pods so that the roof can be immediately installed once the walls and ceiling are in place to prevent the wood from being exposed to the environment for any length of time. It is to this end that Jim Turnipseed and Turnipseed International have been extremely helpful in this process. Not only was all of the steel for the project donated but the team was also able to use Turnipseed International’s welding shop to fabricate the trusses and other steel elements of the project. It was a welcome break from the wood processing to learn about steel and how to weld.

The whole process only took about 5 days. The team spent the first two days cutting down all the members of the trusses, the purlins, the runners, and the plates. The next day, with the help of the men working at the shop, they laid out the truss design on the warehouse floor and welded together a jig. This allowed the team to easily slide the members of the truss in place then weld together each joint. 2 days later, 11 trusses were completed and transported back to Newbern!

Stay tuned for updates as the team returns to Newbern and puts this steel to good use!

Already missing the shop,

The Metalworking Massers

Soundtrack: Dirty Paws | Of Monsters and Men

Horizontal and Vertical Sock Tests

Wondering if the team still masquerades as scientists? Don’t worry, the science lives on. Throughout the construction process, the team has been running horizontal sock tests day and night; four tests a day, every day but Sundays! They have completed a series of small scale horizontal sock tests and are currently working on their first peer reviewed paper. This paper will present their findings on the suitability of wood for Breathing Walls, as well as their initial findings on their vertical sock tests.

Vertical sock testing is the next step in the testing series. As the team scales up the tests, a new variable is added. This series of tests will introduce buoyancy ventilation to the system rather than use forced air with the blower door fan. The sock, currently set up in the team’s living room, is an 8’ tall insulated cone with sensors at the top and bottom logging pressure, temperature, air flow, and humidity. They are currently calibrating this test and hope to finish up the series before Christmas! After that, they’ll move on to laminated panels and eventually to testing the full-size building currently in construction.

The team is off to the big city (Birmingham) again soon to trade off with the Horseshoe Hub Courtyard team in the metal shop. They’ll be taking a rare break from wood and fabricating trusses and other steel components, so stay tuned for updates.

Full of hot air,

The Testing Team

Soundtrack: The Scientist | Coldplay

Laying the Groundwork

The concrete curbs are cured, the formwork deconstructed, and the gravel laid. The site went from a muddy mess to a modern art installation in just a few days with the addition of four concrete monoliths and a field of compacted gravel. Next the team plans to install the termite shields, which are currently in the process of being fabricating, and then construct the floors!

In other exciting news, all the wood for the floors is prepped and ready to go! The team planed, ripped, chopped, and drilled 122 pieces of true dimension 2×8 timber. After ascertaining the scale of this endeavor, they decided to call around and see if any local mills could help them out with the planing and ripping process. Howard Custom Lumber is currently processing the wood for the walls and ceilings (over 700 pieces of wood!) to save the team a little bit (actually a lot) of time.

While the floors were being installed and wood being processed for the walls and ceilings, the team did a quick structural test on the mass timber loft. On a rainy Friday afternoon, they constructed the loft and loaded it up to make sure it wouldn’t deflected when supported on the extreme edges. The mock up was a success, and the loft design is moving forward.

Stay tuned for the heroic return of the wood and its eventual transformation into the first ever Breathing Wall Mass Timber pods!

Sore from moving all that lumber,

The Fearless Foresters

Soundtrack: Graveclothes | Birdtalker

A Solid Foundation

A major milestone in the construction process was reached today for the Breathing Wall Mass Timber Research Project team! The foundations upon which the pods will soon sit are now in place. 

After deciding on the building’s final position on the site and setting up strings, we had an excavator rough out the holes for the footings. This saved us hours of digging and years of back pain. The concrete pour was split into two phases: the first for the footings and the second for the “curbs” that sit on top of the footings and that the pods will sit on. The footing pour didn’t require any form work and we were able to pour directly into the holes once we had placed the rebar. 

The biggest challenge of this process was building and placing the formwork for the curbs. After taking site measurements, we fabricated the forms under the fabrication pavilion. This process required us to make very accurate cuts and ensure that everything we built was completely square. Once we placed the forms on site however, we came to the realization that the height we had spec’d for the curb felt too high. After quickly mocking up different options for the height, we decided to lower the concrete curbs 8 inches. So we had to take the forms back to the fabrication pavilion, take them apart, and do it all over again. Fortunately, it went much faster the second time- the beauty of the design-build process.

Leveling and shoring up the forms was also quite a process. Since our forms were so tall, the strength of the forms was critically important. We ended up with some pretty bulletproof forms that could handle the worst we could throw at them. 

So, concrete! Passing this milestone in our project means we are one big step closer to having a full scale test of the Breathing Wall and gives us the momentum we need to push the project forward! 

Coming soon: some floors for these foundations! (also the rest of the building, but the floors first).

Really pouring our hearts into this project,

The Master Builders

Soundtrack: Iron | yahyel

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.

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