Recently Completed Projects

Graduate Team Completes Construction and Publishes Paper!

The Thermal Mass and Buoyancy Ventilation Research Project (TMBV) graduate students have concluded their work and time in Newbern, AL. In their wake, they leave a published, peer-reviewed paper and two research-ready buildings.

In the course of their graduate year, the TMBV project dove deep into the results of their initial small-scale experiments, culminating in a research paper published in the Journal of Physics: Conference Series as a part of the 2021 CISBAT Hybrid Scientific Conference. At the same time, the team designed and constructed two Test Buildings. The cooling and ventilation effects spurred by the optimized thermal mass will be studied throughout the next year, providing ground truth data for the system at a building scale.

The paper: A synopsis

The open-access research paper entitled, “Synchronized coupling of thermal mass and buoyancy ventilation: wood versus concrete” was published in November 2020 in the Journal of Physics Conference: Series. This was an effort involving the entire TMBV research team including Salmaan Craig, Remy Fortin, Sebastien Asselin, Kiel Moe, David Kennedy, and Andrew Freear. The paper describes small-scale experiments that test the accuracy of sizing parameters which suggest how to optimize the coupling of an internal thermal mass—which allows a building to store heat and thereby avoid major temperature fluctuations—with natural ventilation cycles, regardless of the material or the scale of the building. The results suggest the sizing parameters may be valid for early-stage design. They also show that biomaterials, such as wood, can perform as well as conventional thermal mass materials, such as concrete.

Why is this important? Typical, mechanical thermal comfort systems pump greenhouse gases into the atmosphere, raising the temperature even more. They also cannot perform in power outages during weather events caused by the ongoing climate crisis. Therefore, using regenerative materials, such as wood, to mitigate rising temperatures without reliance on the power grid suggests sustainable thermal comfort with less burden on the environment. That is an ongoing aim of the TMBV Research Project, and these initial results are an encouraging step. Before such lofty goals can be reached, the TMBV Test Buildings will provide more insight into the capabilities of the system.

The buildings: A summary

As stated above, the TMBV Test Buildings examine the coupling of thermal mass and buoyancy ventilation as a reliable thermal comfort system at the building scale. Currently, the buildings are set up for these first large-scale experiments and will later be fitted out for housing. The buildings are designed to be flexible spaces for ongoing experiments as well as dwellings for 3rd-year students. Therefore, the buildings balance valid experimental conditions, the realities of construction, and the basic needs of college students. One Test Building is powered by a plywood internal thermal mass and the other by concrete. Both buildings are designed to achieve the same performance parameters for temperature dampening and ventilation rate despite their material differences—i.e., the surface area and thickness of the material.

The buildings are the first Rural Studio buildings constructed primarily out of Structurally Insulated Panels (SIPs). Towering over the Supershed on Morrisette Campus they hover 8′ off the ground. Underneath the buildings is a gathering space nicknamed the “Cooling Porch.” During the day it is meant to collect cool air flowing out of the buildings, providing a place to enjoy the systems en masse. Air travels here through the extended chimneys, which increase ventilation speed and denote the building’s function.

With such tight buildings, dependent on accuracy, the team showed out on all the details. From three-week welding sessions to mapping out patterns of old sidewalk scrap to calculating the discharge coefficient of rooftop vent caps, this team investigated every inch. Feel free to peruse the TMBV blog to see the process, but for now here are the results.

The team: An abridgement

What a journey! These kids, ready to learn how to craft a beautiful building, were not expecting a crash course in thermodynamics, experimental design, and scientific discourse. It was an incredible opportunity to do both. Blending design, construction, and scientific rigor was an extremely unique and fulfilling educational experience. And the TMBV team sharing that experience across North America!

Rowe, the TMBV team’s certified best and most patient construction instructor, has moved to Bozeman, Montana, to join Love | Schack Architecture.

Jeff, a master of power tools and 3D modeling, is taking time to further his coding and woodworking skills.

Cory, a most relaxed, renaissance man, is enjoying his stint at the Ghost Residency with MacKay-Lyons Sweetapple Architects Limited, in Lunenburg, Nova Scotia.

Livia, the heart and volume of the operation, has settled in Austin, Texas, working with Rural Studio Alums at Thoughtbarn.

A huge thank you to the faculty and staff of Auburn University Rural Studio, the teams’ student colleagues, the project consultants (including Joe Farruggia!), the donors and teachers of Turnipseed International, and “Crane” Shane of Sweetwater Construction LLC for your time, knowledge, and support. Most obviously and ardently, thank you to the TMBV research conglomerate Salmaan Craig, Andrew Freear, Steve Long, David Kennedy, Kiel Moe, Sebastien Asselin, and Remy Fortin for the stellar work and dedication. It took a village!

This lot loves Rural Studio and all of its people. Hope to see y’all soon.

Over and Out

It’s curtain call on the Myers’ Home, construction that is. The team wrapped up just in time for the holiday season and towed away the trailer and all. The keys have been given to the clients. The team can’t wait to hear how the house functions in action. But how about a dive into those last few weeks on site in Newbern?

Flex Walls, Finally

One of the primary aims of the Myers’ Home was to provide a formwork for varying generation needs. The team explored this concept by building the “shell” house with no spatial divisions outside of the “core” volume. With this method, a client could hypothetically walk through the full-scale model of the home. With full experience of the space, they can decide where they’d like bedroom divisions from several schemes.

These “flex walls” are stud walls constructed in place, rather than tilt up, and anchored with a few masonry screws. They are paneled with sanded and primed plywood and fasteners are entirely visible. These details allow the walls to be more easily altered or removed years down the road. If the family is in need of a new room configuration, these walls can handle it.

Bits and Bobs

Of course, at the end of every building project there is what’s called a “punch list.” It’s a list of the remaining tasks to ready the house for turnover. On this list for the Myers’ Home was a few coats of finish to the butcher-block countertops, making the stair handrail, caulking the last of corners, tightening up door hardware, and sealing the interior and exterior slabs.

Porch Conclusions

Another final task was to complete the lower row of siding on the front exterior face of the home. A quick task that certainly visually completes the house quickly!

With all bents in place and secured, we begin raising and securing purlins. Then, we welded the purlin mats at the same time as the bents and installed them as single units by bay. Riley took the reins and began welding up a storm while the others clamp and shimmy the pieces to level.

Finally, we wrapped up the roofing, a quicker job than expected. After just a day and a half the team completed the final line of siding and the porch roof. The panels went on with slightly more precision than the main roof. The tapping screws needed to catch the 1-1/4″ purlins, so measuring and pre-drilling of the sheets and purlins were required.

With a final coat of sealant to the interior slab and porch pavers, the house was ready for move-in!

That’s a Wrap

Madeline, Judith, and Riley are on to new endeavors, though questionably bigger and better than this one.

Start spreadin’ the news! Riley is kicking it in the Big Apple, starting work at MADE Design/Build in Brooklyn, NY. With an in-house woodshop and IKEA next door he’s sure to be up to his ears in miters and meatballs.

Judith is sticking around Newbern and joining the teaching team as 3rd-Year Instructor/Coordinator. She’ll be working on Rosie’s Home with Emily McGlohn and the new batch of 3rd-year students. Hale County just can’t seem to shake her off!

Madeline has hit the road to Bozeman, MT, where she’ll be working at Minarik Architecture. She’s pleased with her new snowboarding opportunities and excited to get into conscious and contextual residential work. Stay thawed up there!

The team could not be more grateful for the support of Rural Studio faculty and staff, student colleagues, consultants, donors, and friends. It’s not goodbye, it’s see you later. This is the Myers’ Home team signing off.

Bit by bit, day by day

Everything is officially clad! The plywood is cut! The benches are designed! The Cooling Porch is secured! The wiring is installed! The door is installed!

Rowe and Jeff are ticking big items off the Thermal Mass and Buoyancy Ventilation Research Project checklist. Let’s take a look at what the graduate research team has completed in the last month.

Clad

The Cooling Porch ceiling and Bottom Chimneys were clad last as they did not need the articulating man lift to reach. Now that the entire Test Building is clad with bleach-stained cypress, their form reads less like floating boxes and more like floating funnels. While the main function of the chimneys is to increase overall stack height and therefore air velocity within the system, they also signal movement to onlookers. Two wood-clad heat silos at your service!

Cut

Another TMBV jig on the books, this one helps break down large pieces of plywood with precise cuts. Jeff and Rowe designed and built the jig to make all the cuts necessary for creating the plywood thermal mass panels. Like the concrete panels, the plywood conforms to the slanted ceiling of the Test Building. There is also substantially more plywood panels as they cover the walls, floor, and ceiling of the interior.

Secured

Next up, the Cooling Porch finishing touches. Steel plates for future benches were installed in the construction of the Cooling Porch walls. However, the bench material was undecided. The team chose to use the same metal grate used on the stairs and walkway for these breezy benches. Over the next couple of weeks, the benches will be installed and reinforced with a bracket.

Last up for the Cooling Porch, a little tripping hazard prevention. The top course of the Cooling Porch walls were dry-stacked but untethered to the ground. To keep the course in place, the team used Tap Con masonry screws and small metal brackets to link the top course with the rest of the wall.

Powered

As future dwellings and experiments, the Test Buildings need power for people and sensors. The buildings are wired through chases in the SIP, accessible from floor outlets to keep the walls clear.

Last on our list of tasks completed is the installation of the doors! The test fit showed a bit more blocking needed, but the end result looks great!

Meet Me on the Porch

The Myers’ Home team has been busy preparing the porch structure on the Western face of the home. This porch is unique among previous Rural Studio projects for a few reasons: It’s fabricated from steel, has its own slab, and barely touches the rest of Myers’ Home.

Mildew, Mil-don’t

Looking back, the home was designed for longevity and flexibility through generations. In previous Rural Studio homes with front porches, the space is most often subtractive. This means that the open porch is carved from the main volume of the house and its structural system. In doing so, the rafters are exposed and gaps between trusses are exposed. These must be filled in some way, usually bird blocking. The other solution is a soffit under the eaves.

In both cases, the exposed undersides of the rafters or soffit are nearly always in shade and tend to mildew. Over time the uncovered portion of the truss or rafter can degrade faster than the interiorized segment. In these cases the whole member is still compromised.

The team addresses this problem by eliminating the condition entirely. Myers’ Home has no true eaves, only a slight overhang of the corrugated roofing material. Flashing details are tight and the long Western porch is entirely removed from the structure of the house.

Finding Your Footing

But how’s that little gap mitigated? A separate foundation for the porch is planned. Ideally, this job could be completed with just the team and some extra hands in one morning. This settled into five separate pavers, with two inches of gravel between and roughly a foot of separation from the main house slab.

Before the pavers can be placed though, footings for the metal columns of the porch must be set. This system shook out to be a trench footing, with ten-inch-deep reinforced footings at the columns and a six-inch-deep trench spanning each bay.

Couldn’t do it without a little help from our friends!

With the help of a handful of 5th-year students and professors Andrew Freear and Steve Long, the pour was complete in just about an hour with all levels squared away. The team can look on to the next pour the following week of the pavers.

Prep for the latter involves formwork once again, this time with removable dividers between eight by eight-foot segments. These folks took a leaf out of Horseshoe Courtyard‘s book and used a system of stakes and plywood strips for this maneuver. They then mound backfill dirt around to keep concrete from spilling out beneath the forms. The last step before the concrete arrives is reinforcement with metal mesh and grade pins. The mesh strengthens the concrete as it settles over time and grade pins are fluorescent marked stakes driven to signal the correct level of concrete in the forms.

Finally, the team can tackle their third and last concrete pour of the project. The truck arrived and they were soon in the groove of a process with aid of Patrice’s Home team and Steve. Riley manned the chute; Judith, Daniel, Adam, and Lauren shoveled and screeded; Madeline and Lauren troweled and floated away; and Steve edged each one.

These pavers, being on the porch, are also exposed aggregate which necessitates an additional step after the concrete is finished but still wet. Following a half hour’s wait, Judith misted a specialized concrete retarder atop the fresh pavers, bright ectoplasm green. This allows the majority of the concrete to cure normally while the topmost layer of cement is kept a slurry.

After roughly eight hours, Madeline and Judith return in the evening to hose and scrub the surface of the pavers and wash away the cement. This reveals a texture of the aggregate, in this case pea gravel specially ordered for this type of slab. The team is aiming for a change in surface material between the concrete of the porch and that of the interior as well as a more rugged finish for the home’s entrance.

Weld, Weld, Weld

These three can now focus on the porch structure itself, made entirely of metal with a corrugated roof to match that of the main home. Thanks to the generosity of Studio friend, Jim Turnipseed, the team was able to spend about a week in Columbiana, Alabama at Turnipseed International’s metal shop. There they built jigs, practiced welds, fabricated purlins, and built bents.

With the oversight of teachers Flo and Luis, they quickly learn the equipment, cut pieces to length, and weld up a storm.

Purlins are up first, a good practice run as most welds will be hidden from sight. For east of installation and transport, purlins are designed as mats. These mats are welded in a line and installed as a single unit in each bay. Tables are placed a specified width apart and a simple rectangular jig is made with four ninety-degree angles to catch the mat’s corners.

The bents are pitched with a solid four-inch-wide plate welded atop to catch the purlin mats and provide more tolerance. These take more complex jig-work. The needed angle cannot be achieved in the range of the band saw’s angle. So the extra distance is made up by welding a separate tray to make up the difference.

Following this, the angle for the bents’ top and bottom knee-joint are welded to the tables similarly to the purlin jig. Once the pieces are arranged, baseplates with holes drilled are attached to the bottom of the columns. These baseplates are what will anchor the porch structure to the footings poured earlier.

A big ol’ stack of purlins

The final step in fabrication is to prepare the members for galvanization. A series of half-inch holes must be drilled in all pieces to allow them to drain. This is relevant when components are dipped in the zinc bath stage. Results can be…explosive, otherwise.

Let’s Taco ’bout Halloween

The welded component are shipped off to Mississippi for galvanization! The team is on their merry way back to Newbern to continue site work. But several days earlier the team returned to Hale briefly for the annual Halloween Reviews! Those who may have spent a few days in this neck of the woods may recognize the wall murals from Greensboro’s own Mi Tenampa Mexican restaurant. As leftover students from the previous year, these three spend review day listening in on new thesis and 3rd-year work, attending the costume contest, and eating quite a few Reese’s peanut butter cups.

a red pepper and two human-sized cactus cardboard cutouts stand in front of three people

Bringing Down the Hammer(drill)

While waiting on the return of the porch structure, Madeline, Judith, and Riley move back into finishes and porch groundwork.

Judith and Riley borrow the Studio’s hammer drill and a masonry bit and spend a morning drilling four six-inch-deep holes in each footing. Riley has a specialized jig that expedites the process. After snagging only a bit of rebar, they’re ready for the next stage. Threaded rods are anchored into the holes with epoxy, these will catch those baseplates on the porch columns. With a system of threaded rods and nuts, the team can micro-adjust the levels of the bents upon installation.

That’s what’s going on around town, catch the final stages of finishes soon. Myers’ Home is getting fitted out with cabinetry, sinks, stair treads, and more!

Cladding, Concrete, Continuing

The Thermal Mass and Buoyancy Ventilation Team’s days of pouring concrete and manning the man lift are over. All of the internal thermal mass concrete panels have been poured, cured, and installed in the Concrete Test Building. Another milestone hit is the completion of the exterior cladding (minus the Cooling Porch ceiling). The team waved goodbye to both the articulating man lift, generously donated to the project by Sunbelt Rentals, and to team member Livia. She journeyed to Austin, TX, to work for Rural Studio Alum Lucy Begg and Robert Gay at their firm, Thoughtbarn. Good luck Liv!

Let’s check out the progress!

Cladding Completion

The team met their goal of finishing all cladding which required the articulating man lift by the end of October. The bleach-stained cypress covers all exterior surfaces including the Chimneys. The team left one side of the cladding longer than necessary. Then they came back with a skill saw and a guide to give one clean cut. This ensured that all corner reveals were exactly 1/2 inch wide.

Interior Optimized

Over 70 1-1/8 inch concrete panels now line the walls of the Concrete Test Building. The team crafted formwork and processes for pouring, transporting, and installing each panel. Behind the panels is 1/2 inch rigid insulation which creates a thermal break from the OSB sheathing during the testing phase. For roughly the next year, the Test Buildings will be unoccupied as temperature and ventilation measurements are continuously recorded. Afterward, the Test Buildings will be prepared for either more experiments or occupation by 3rd-year students living on Morrisette Campus. Check out the nearly complete Concrete Test Building below! Only some buffing and shining to go!

Bonus!

Also in the works as of late is a vent cap for the bottom chimney opening within the Test Buildings. This cap seals the lower ventilation opening shut during winter occupation. Seen below is Rowe welding a frame for the hatch!

Don’t miss Jeff and Rowe’s wonderful Halloween Review costumes. Jeff as his prized Milwaulkee leaf blower and Rowe, a leaf, one of many victims. Keep checking back in as the Test Buildings near completion!