Some of the lingering warmer season crops are still yielding, like eggplant, peanuts, and bell peppers.
Mostly we have been busy planting seeds into soil blocks and direct-sowing with the push seeder. These crops are lettuces, mustard greens, baby brassica greens, carrots, beets, chard, collard greens, rutabagas, broccoli, radishes, spinach, hakurei (salad) turnips, and turnips.
Once the seedlings are ready, we prepare the beds and transplant out all the crops.
We have been reaping great harvests of many of these crops too, with all of Rural Studio’s daily green salads coming straight off the farm.
Now that the weather is beginning to cool, we have also been preparing for winter by sowing fall cover crops to leave in the field for overwintering. This ensures that there is always something growing in the beds, which helps with drainage and compaction and overall soil health. In the spring, these crops will be mowed down, adding good organic matter back into the soil.
Finally, we are also preparing the greenhouse for production over the winter, which is where most of Rural Studio’s food is grown in deep winter.
Live from behind a stack of full-scale detail drawings, it’s the Thermal Mass and Buoyancy Ventilation Research Project Team! Lately, the team has been investigating all details inside and out. Starting out with material pallet and ending up at chimney flashing, the team is kicking it into high gear.
Unsurprisingly for a project so focused on the interior systems, it was difficult to make decisions regarding cladding. Initially, as seen in previous models shown above, the team experimented with separate cladding systems for the chimneys, Cooling Patio ceiling, and exterior walls. For iteration 1 of the test building design included a timber open-joint cladding system wrapping every surface. Next, for iteration 2, the cladding system wrapped only on the exterior wall faces of the buildings and the adjoining chimney faces. However, thin sheet metal covered the roof, cooling patio ceiling, and the chimney faces which touch those surfaces.
The consistent cladding of iteration 1 appealed better to the monolithic nature of the SIPs structure. It also reinforced the importance of the chimneys to the buildings as a whole from the exterior. From there the team began to test if the timber was the correct mono-material for the test buildings. Seen above are renderings testing different materials for the cladding, columns, retaining walls, and benches. It is important to view these materials as they interact in the Cooling Patio. While sheet metal and polycarbonate cladding options may look more monolithic, timber is a low carbon material that better represents the heart of the project. In some cases, timber as a building material acts as a carbon-sink meaning it stores and processes more carbon than it produces. This of course relates strongly to the passive goals of the Thermal Mass and Buoyancy Ventilation Research.
Recycled Retaining Wall
Now the team is settled on the timber cladding, but they are not convinced of the retaining wall and bench materials. These aspects want to be a more earthen material as they rise from the ground towards the test buildings. After investigating rammed earth and concrete, the team wanted to find something more stackable. Concrete and rammed earth are beautiful, but they require formwork which requires more time. Something stackable will give the team more flexibility as well as members are movable.
Thankfully, down here on Highway 61 road work is being done to remove a load of 8″ x 8″ x 8′ stackable concrete barriers. The TMBVRP team is getting their hands on some of these reusable members and are calling around to local highway departments to find more similar materials. If they find enough, they will have a durable, stackable, and reusable material for their Cooling Patio. They can also use the old sidewalk pieces as a mosaic, ground material for the Cooling Patio. Above are drawings showing the use of these recycled materials.
Structure and Detailing
For the past three weeks, the team has been meeting consistently with Structural engineer Joe Farrugia. He is guiding the team through lots of math to size their columns. While the gravity load on the columns is extremely manageable, the wind load is more difficult. The test buildings height means they will face more wind load than a structure this size typically experiences. However, Joe is confident that the structural system the team has chosen is doable with the correct column sizing.
While the team is attempting to draw every detail of the test buildings, they’ve found the trickiest spots to be around the chimneys. Making sure water moves off the roof consistently and air moves behind the ventilated screen is crucial. The TMBVRP will spare you the pain of walking through each flashing bend and board cut. Struggles emerge when the chimneys converge with the angled roof, but it’s very doable with lots of thinking, drawing, and redrawing. Then Andrew Freear and Steve Long, come in to save the day because how you’ve redrawn it five times is still wrong. Lots of covered wall reviews later and the TMBVRP team is on their way to compiling all the details in a digital model and drawing set.
Looking forward to keeping this momentum going, the TMBVRP can be found in Red Barn from dawn to dusk. Feel free to bring by some late-night snacks but for now thanks for TUNING in!
Between portraits of Russian monarchs, a stroll through a Greek themed yard, and getting to feed some chickens, Oak Hill is definitely the most unique house tour the students have had the honor of partaking in. Before COVID, the owner had thrown a Russian monarch themed party and chose to keep some decorations. One room is filled with colorful furniture, beautiful glass vases, and extravagant curtains. In another room portraits of Russian monarchs hang by string like they would have been in the 1800s.
Outside, classical Greek-styled statues stand side by side with modern takes on the statues. Some pieces are left to be “dissolved” back into nature. After the tour, the students drew an elevation of the main house and of the cabin, which we believe turned out pretty great.
Shop class has been filled with exciting new ideas and crazy curves. Steam bending, while frustrating at times, has opened a whole new world of woodworking to the students. It will be exciting to see how our curvy wood works will turn out!
Ophelia’s Home Site
To finish truss prep-work, large bolts were put through the beam to fully brace it, and the columns were given another layer of bracing. All the prep work payed off because the trusses went up fairly easily. Steve Long came out to site with the Bobcat, the studio’s skid steer loader, to provide some much appreciated help. Steve long used the Bobcat to first lift a truss, guided by 3rd-year Ethan, above the walls. Then a team of 3rd years with Professors Emily McGlohn and Chelsea Elcott directed the trusses into place and adjusted them until plumb. Temporary bracing was put on the trusses as everyone held them in place.
Once all the trusses were on the walls, and they were put in the correct spots, permanent bracing started going up. Next week, the rest of the permanent bracing will be placed by the roof and enclosure teams while the framing team starts work on the front porch! We are so excited to have the roof raised and to be finally building Ophelia’s front porch!
Live from—wait, is that a 3′ x 4′ concrete panel? Lately, Thermal Mass and Buoyancy Ventilation Research Project Team has been delving into the interior of the test buildings. Inside, Wood and concrete thermal mass line the walls of the test buildings. The thermal masses thickness and surface area are optimally proportioned based on the thermal properties of the materials, size of the room, and ventilation required. This proportioning makes the whole passive temperature and ventilation control strategy tick. Therefore, the TMBVRP team must figure out an elegant solution for hanging the thermal mass to create a beautiful interior which also operates optimally. Let’s take a look at how they are tackling this task. Hint: it involves very big concrete panels …
Typically, designers think of concrete as the go-to material used in passive thermal mass strategies. This is why the TMBVRP team is testing it in the Testing Buildings alongside the more surprising material; Southern Yellow Pine. If you remember from previous posts when the materials are proportioned properly using the Optimal Tuning Strategy they can be equally effective at cooling and creating buoyancy ventilation cycles.
However, when it comes to hanging the two materials on the SIPs walls, Pine is obviously much more straight forward. The pine boards attach to the SIPs panel walls with a simple screw. Well, multiple simple screws. On the other hand, the team will have to get much more creative to secure the concrete panels.
To start, the team tested two strategies hanging concrete panels; masonry anchors and cone form ties. First, they cast the masonry anchors and cone form ties into two 12″ x 12″ concrete panels. Similar to the panels in the Concrete Test Box in size, but different in the attachment system as the security of the panels in the test box is far less crucial as no one will be sleeping in it. Both test panels are attached at all four corners to shear walls in the Red Barn.
Masonry anchors are fluted plastic chambers that adhere to the concrete and are screwed through tp attach concrete to wall. They allow for a connection point that looks as if the screw passes directly through the concrete. However, for the sake of durability, the team would include a washer in this scheme to keep the screw from bearing into the concrete.
Likewise, the cone form ties act the same as the masonry anchor, but are larger in diameter and thickness. Also, they are able to set into the concrete to create a nice reveal. While the team liked the effect of this reveal, team collaborator Professor Salmaan Craig revealed a possible hurdle for the experiment. Revealing edges at the attachment points could slightly disturb the direction of heat transfer. The direction of heat transfer is integral to the strategy which is why the panels are insulated on the back. And, while this is a very small area that could be affected it is multiplied enormously by the number of panels and screws. We call this problem, fastener effect loss. Fastener effect loss assumes, very conservatively, that the small area around the reveal is ineffective to the system.
Next, the team ran the numbers and if all the panels were 12″ x 12″ with four form ties each, 6% of the thermal mass would be lost to faster effect. Now, that’s not bad at all for a real building, and again that’s an extremely conservative estimate. However, for an experiment establishing the most ideal situation for a small building, 6% is not negligible enough. Going forward, if the team prefers the cone form ties, they will need to lessen the amount of panels therefore lessening the number of form ties. Fewer form ties means less fastener effect loss. Fewer form ties also means bigger panels. The team sketched out many different possible panel arrangements but decided they needed to test just how large they could cast a concrete panel. Above on the far right, you will see their biggest panel possible design. This design consists of 3′ x 4′ panels in a running bond pattern.
Next, Jeff and Rowe got to work creating the panels for biggest panel possible design. The estimated weight for these panels is 200 lbs. While this is fairly difficultl for construction, the size of panel cuts down on the number of panels needed from 128 to 39. So while it may be hard to lift, the team would have to make far fewer panels. And the fastener effect loss shrinks exponentially as the design goes from using over 500 screws and form ties to under 200. The question still remains, however, will the panels crack at this size?
To address the issue of cracking concrete panels, the team tested two different mixes for their large panels. If you remember from their blog post on concrete thermal property testing, the team obtained the thermal property data from three different standard concrete mixes. They ended up using the Quikrete Pro-Finsh for the Concrete Test Box, but thought for the large panels they should also try the Quikrete Fiber-reinforced mix. The fiber-reinforced mix is increased in structural integrity which will be beneficial for larger panels by reducing possible cracking. Jeff and Rowe built two form works to test both mixes at the 3′ x 4′ panel size.
Look at that! Both the fiber-reinforced and smooth finish concrete mixes came out great! Very smooth with zero cracks, but very heavy. Above you see the fiber-reinforced panel which turned out just as good as the professional finish and would be much stronger. This does not mean that the team will be using the enormous panels, most likely they will cut them in half. However, the team now knows their largest limit on size is possible. The team will continue to weigh their options between attachment method, panel size, and panel arrangements as they solidify their design. Keep tuning in to see where these crazy kids and their crazy concrete end up!
This week 3rd-year students started a new project in woodshop class which taught them the technique of steam bending. The project brief is quite open ended; make something “useful” using steam bending. The open nature of instructions will help students really use their creativity. After the great results from the cutting boards, it will be exciting to see what students come up with next!
In history this week, Dr. Hudgens had the students complete their final Design Problem for the semester. Third years have now completed 3 of these Design Problems and look forward to their final review on their last Monday at Rural Studio, November 23rd.
At Ophelia’s Home this week students continued to prepare for the incoming roof trusses. They put up a beam on the front porch of Ophelia’s home which the trusses connect to in order to create a covered outdoor space. Trusses will span from the back, western wall to the front, eastern wall and over the front porch, resting on the beam. The roofing team placed the brackets, called hurricane ties, on the top plates of each wall for the trusses to secure into. The Enclosures Team and the Framing Team worked together to level the columns on the porch. They also attached the beam on which the trusses will rest. A meeting with Professor Emily McGlohn’s father – a structural engineer – helped solidify the roof team’s trusse placement and bracing. Now that Ophelia’s Home is prepped for the trusses, it’s time to raise the roof!