Right now the Thermal Mass and Buoyancy Ventilation team is all about concrete and cypress. They’ve been busy creating and installing the shiplap jointed, 1-1/8″ thick concrete internal thermal mass panels. These panels line the walls of one of the Test Buildings and create the designed cooling and ventilation effects. With Jeff at the helm of formwork building, they’ve completed three out of four panel pouring phases. The panel-making process is separated into phases, so most of the formwork can be used more than once, eliminating waste. Formwork, or molds, are fabricated with precision in the woodshop. The team installed phase 1 before Cory began his journey to Nova Scotia to participate in a residency with McKay-Lions Sweetapple Architects Ltd. Congratulations Cory, we miss you already!
Also on the agenda as of late; exterior finishes! With weather-proofing complete, the team has taken to installing the cladding part of the ventilated cladding system. This system is completed with 8″ and 6″ cypress boards which are protected with Cabot® Bleaching Stain. The stain also helps the wood age consistently in the sun. With Livia cutting and Jeff and Rowe installing, the cypress siding is flying up!
Unseen are the myriad of other little things the team is finishing up such as electrical and grading. The team is keeping the momentum up so stay tuned to see the buildings fully wrapped!
Live from Newbern, Alabama, it’s the Thermal Mass and Buoyancy Ventilation Research Project Team! 77 weeks in Hale County and the graduate student team is still firing on all cylinders. This post, they’ve got updates on concrete panels, drainage, and the steel walkway and stair. Plus, the wonders of the Wood-Mizer, a portable sawmill, for those readers who make it to the very end!
Panel Pour Product
A couple of weeks back the TMBV team poured four, new concrete panels. These panels were designed to test tongue and groove joining system. Also, this round of test concrete panels experimented with vertical formwork.
As predicted during the struggle of formwork construction and concrete pouring, the vertically poured panels did not turn out so well. However, the team made promising headway with the new joining method. Alright, now that the panels have cured, let’s take a look at the material.
First, you’ve got to remove the panels from the formwork. You know from the team’s previous post that one of the vertically poured panels did not make it all the way through pouring. Look at that; live edge concrete!
However, the smaller vertically poured panel survived! The results were surprising, as seen above this panel had more air gaps than the traditionally poured panel. The students previously thought having formwork on all sides would create more even and consistent panels. But, without an open surface to trowel, the vertically poured panels were subject to more air bubbles.
The typical, horizontally poured panels turned out smooth and even as ever. And just look at that grooved edge!
Next, the concrete panels were attached to the Fabrication Pavilion pin-up wall to test the joints. The results were inconclusive. Some tongue and groove joints turned out well, while others broke at the edges of the panel. Going forward, the team wants to attempt a shiplap joint for the panels. Also, they’d like to make more, smaller test panels to assemble in a miniature wall configuration.
As you can imagine, in the everchanging weather of late, the Test Building site became the town swimming pool. The 18″ deep hole containing the foundations was nearly filled to the brim during the past weeks’ rain. Luckily, the team, Mason, and a mini excavator got out while the sun was shining to install the drainage. The French drain leads from the Cooling Porch, betwixt the foundations, into the forest line.
Walk this way
You might have been wondering how one day you might access the 30′ tall, 8′ above ground Test Buildings. Well, you’ll use the steel ships ladder and walkway of course.
As of late, the TMBV team students have been designing the fabrication and installation process of the stair and walkway. To detail the stair fabrication process, they partook in a classic rural studio technique; the cartoon storyboard.
Next, the team planned out the order of installation of the walkway and the SIPs structural floors. First, they plan to place and secure one assembled SIPs Test Building floor. Second, place the other Test Building floor, using the walkway steel angle frame to square the two to one another. When everything is properly adjusted, lag screw the steel angle frame to the SIPs floors. Third, place 1″ metal grate on top. Next, place and bolt the stair to the walkway and ground connection. Lastly, site weld the handrails to the exterior face of the steel angle frame. Voila! It’s that easy if you only have a crane!
And the special bonus; a portable sawmill! Adam Maggard, an Auburn University Forestry and Wildlife professor and Extension Specialist in Forest Systems Management, travels the southeast with the Wood Mizer portable sawmill conducting forestry management research and reaching out to family, forest land owners. Adam collaborates with Auburn Architecture Professor and TMBV colleague David Kennedy and Rural Studio Alum Will McGarity. The three gave the students a Wood-Mizer tutorial as well as an introduction to their research.
Rev. Walker’s Home Project team requested the visitors to help mill some gorgeous tree’s from Rev. Walker’s land. Each student took a turn milling down either the cedar or pecan tree. The students were amazed by the machine and even more amazed that freshly cut cedar is bright, pink. It was a remarkable experience, big thanks to Adam, David, and Rev. Walker from the Thermal Mass and Buoyancy Ventilation Research Project Team!
Live from Neck Down week, it’s the Thermal Mass and Buoyancy Ventilation Research Project team! From 8:00 AM to 3:00 PM last week, the 3rd-years, 5th-years, and graduates students have bonded over manual labor and project maintenance. This is the age-old tradition of Neck Down week, the start of each semester in which all year levels put their projects aside to spruce up Rural Studio’s campus and help out at ongoing and completed projects. The TMBVRP team snuck in some more concrete panel test pours in the after hours. Let’s see how they did it!
Before we dive into construction, it’s important to highlight what is different about these concrete panels. In contrast to the team’s last test pours these panels are smaller with tongue and groove edges. We will dive deeper into the tongues and grooves later. As seen above in the unfolded wall elevations above, the team experimented with different sizes and arrangements of panels. The main difference in the schemes where whether the running bond pattern stacked vertically or horizontally. The teams chose to test pour the more rectangular panels from both the vertical and horizontal running bond options.
For both chosen designs, the team planned to test making the most commonly recurring panel and the trickiest panel. Therefore, for each option the forwork for a typical rectangular panel and the more triangular panel, created by the sloping roof, was designed. However, a certain, not-Livia team member created the “construction” drawings seen above months before actual construction. The team has made significant leaps and bounds in construction drawing etiquette since. There was also much to the tongue and groove formwork that had not been fully fleshed out. So, as seen in the marked-up construction drawing above, much was decided on the fly. It was a very design-build experience.
Next, the team used their new tongue and groove router bits. Tongue and groove is a system of joining adjacent panels by means of interlocking ridges and grooves down their sides. Seen above are the first tests of the router bits to create the tongue edges for the panel formwork. For the formwork, the tongues and grooves were routed out of PVC board. PVC board will not chemically bond with the poured concrete, therefore, creating a successful cast. Connecting the concrete panels to one another using the joining system will improve their strength. The panels will act more as one structurally, but also thermally making a more effective thermal mass.
Horizontal Panel Pour
Along with testing the tongue and grooved edges, the team attempted two different pouring strategies; horizontal and vertical. Seen below is the typical, horizontal panel pour method. The team is pretty well-versed in this recipe. After pouring the panels, the team will let them cure for about a week. Onwards to the vertical pour!
Vertical Panel Pour
The vertical concrete formwork meant to create two perfect panel faces and ease panel transportation. However, you guessed it, the vertical pour was quite difficult. First, vertical formwork requires more pieces that need to fit together more precisely. You are in a sense making a very precise sandwich that leaks Mayonaise everywhere if you don’t get it right. Second, getting the masonry anchors to stay in place and attach through both large faces required a special bolting jig. Another new piece to make. Third, to keep the formwork upright required leveling and sawhorse structure. Fourth and finally, the team built a funnel to transfer the concrete through the 1-1/8″ formwork opening. And repeat for 60 plus panels!
While the smaller, triangular vertical pour went fine enough, the large rectangular panel busted open. As you can see above the triangular panel had little leakage out of the masonry anchor attachment areas. The rectangular panel however suffered catastrophic failures in this area. For now, the team awaits the curing process to see the results. However, based on these vertical tests they aren’t sure the reward will be worth the hassle. But, hey, where else in the world do you get to test pouring concrete panels vertically than in the Rural Studio graduate program? It’s always worth the hassle.
The Wood Rack
Last, but far from least, the team can’t wait to show off their new wood racks. Because the Fabrication Pavilion is their construction headquarters, the team was in charge of cleaning it up as a Neck Down week task. They are stupidly proud of these wood racks they built to take all their lumber vertical and clear space for more activities! Please admire them!
Copper has joined to say thanks for tuning in! Stop by next week to see how the panel pours and tongue and grooving worked out for the Thermal Mass and Buoyancy Ventilation Research Project Team!